235-474: Haast's eagle ( Hieraaetus moorei ) is an extinct species of eagle that lived in the South Island of New Zealand , commonly accepted to be the pouākai of Māori mythology . It is the largest eagle known to have existed, with an estimated weight of 10–18 kilograms (22–40 pounds), compared to the next-largest and extant harpy eagle ( Harpia harpyja ), at up to 9 kg (20 lb). Its massive size
470-483: A buff colouration. In worn or bleached plumages these light areas can be even paler at times, ranging to almost whitish, which can render a resemblance in such eagles to a washed-out bald eagle. Some of the palest birds can appear anywhere from cream-tawny to light greyish. It is thought that in some populations perhaps paleness increases with age, although it is possible that there is an historical genetic factor to these pale variations. In contrast, some adults can also be
705-438: A food chain who lose their prey. "Species coextinction is a manifestation of one of the interconnectednesses of organisms in complex ecosystems ... While coextinction may not be the most important cause of species extinctions, it is certainly an insidious one." Coextinction is especially common when a keystone species goes extinct. Models suggest that coextinction is the most common form of biodiversity loss . There may be
940-630: A hallux-claw of possibly up to 11 cm ( 4 + 1 ⁄ 2 in). The Philippine eagle might be a particularly appropriate living species to compare with the Haast's eagle, because it too evolved in an insular environment from smaller ancestors (apparently basal snake eagles ) to island gigantism in the absence of large carnivorous mammals and other competing predators. The eagle's talons are similar to modern eagles, suggesting that it used its talons for hunting and not scavenging. The strong legs and massive flight muscles of these eagles would have enabled
1175-657: A nautilus to the Royal Society that was more than two feet in diameter, and morphologically distinct from any known living species. Hooke theorized that this was simply because the species lived in the deep ocean and no one had discovered them yet. While he contended that it was possible a species could be "lost", he thought this highly unlikely. Similarly, in 1695, Sir Thomas Molyneux published an account of enormous antlers found in Ireland that did not belong to any extant taxa in that area. Molyneux reasoned that they came from
1410-415: A species or a population is the variety of genetic information in its living members. A large gene pool (extensive genetic diversity ) is associated with robust populations that can survive bouts of intense selection . Meanwhile, low genetic diversity (see inbreeding and population bottlenecks ) reduces the range of adaptions possible. Replacing native with alien genes narrows genetic diversity within
1645-591: A species pair with the bald eagle ( Haliaeetus leucocephalus ), which occupies a similar niche in North America. The first formal description of the white-tailed eagle was by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae under the binomial name Falco albicilla . The genus Haliaeetus was introduced in 1809 by the French naturalist Marie Jules César Savigny in
1880-436: A viable population for species preservation and possible future reintroduction to the wild, through use of carefully planned breeding programs . The extinction of one species' wild population can have knock-on effects, causing further extinctions. These are also called "chains of extinction". This is especially common with extinction of keystone species . A 2018 study indicated that the sixth mass extinction started in
2115-474: A Lazarus species when extant individuals were described in 2019. Attenborough's long-beaked echidna ( Zaglossus attenboroughi ) is an example of a Lazarus species from Papua New Guinea that had last been sighted in 1962 and believed to be possibly extinct, until it was recorded again in November 2023. Some species currently thought to be extinct have had continued speculation that they may still exist, and in
2350-447: A cascade of coextinction across the trophic levels . Such effects are most severe in mutualistic and parasitic relationships. An example of coextinction is the Haast's eagle and the moa : the Haast's eagle was a predator that became extinct because its food source became extinct. The moa were several species of flightless birds that were a food source for the Haast's eagle. Extinction as
2585-429: A common ancestor with modern horses. Pseudoextinction is much easier to demonstrate for larger taxonomic groups. A Lazarus taxon or Lazarus species refers to instances where a species or taxon was thought to be extinct, but was later rediscovered. It can also refer to instances where large gaps in the fossil record of a taxon result in fossils reappearing much later, although the taxon may have ultimately become extinct at
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#17328838009322820-487: A considerably more massive and paler bill, which is yellow even in juveniles unlike in bald and white-tailed eagles. Juvenile Steller's sea eagles are a distinctly darker soot colour than juvenile white-tailed eagles with even less whitish showing on the body than the latter species but, on the other hand, the underwing often as white marked as juvenile bald eagles (dissimilarly from juvenile white-tailed eagles), albeit in different pattern. In all three large northern sea eagles,
3055-458: A dozen gulls are known in the prey spectrum from the smallest to all four largest extant species. In the United Kingdom , northern fulmar ( Fulmarus glacialis ) are noted as a common prey species and as such may contribute to locally high levels of DDT and PCB chemicals in nesting eagles. However, fulmars defend themselves by regurgitating a smelly, tar-like oily substance that can impair
3290-399: A fact that was accepted by most scientists. The primary debate focused on whether this turnover caused by extinction was gradual or abrupt in nature. Cuvier understood extinction to be the result of cataclysmic events that wipe out huge numbers of species, as opposed to the gradual decline of a species over time. His catastrophic view of the nature of extinction garnered him many opponents in
3525-421: A few attacks also start to exhaust the eagle, as one immature gave up after 15–28 attempts at a little grebe ( Tachybaptus ruficollis ). While bald eagles may attack diving ducks in the same way, they appear to do so somewhat less regularly and successfully. White-tailed eagles usually have less success hunting dabbling ducks because their normal predator response behaviour is to take flight. In one instance,
3760-801: A few cases. This wingspan is broadly similar to the larger range of female size in some extant eagles: the wedge-tailed eagle, golden eagle ( A. chrysaetos ), martial eagle ( Polemaetus bellicosus ), white-tailed eagle ( Haliaeetus albicilla ) and Steller's sea eagle ( Haliaeetus pelagicus ) are all known to exceed 2.5 m (8 ft 2 in) in wingspan. Several of the largest extant Old World vultures , if not in mean mass or other linear measurements, probably exceed Haast's eagle in average wingspan as well. Haast's eagle's relatively short wingspan has sometimes led it to being incorrectly portrayed as having evolved toward flightlessness , even though evidence strongly suggests that it flew. Instead, its short and broad wings represents an evolutionary departure from
3995-708: A higher risk of extinction and die out faster than less sexually dimorphic species, the least sexually dimorphic species surviving for millions of years while the most sexually dimorphic species die out within mere thousands of years. Earlier studies based on counting the number of currently living species in modern taxa have shown a higher number of species in more sexually dimorphic taxa which have been interpreted as higher survival in taxa with more sexual selection, but such studies of modern species only measure indirect effects of extinction and are subject to error sources such as dying and doomed taxa speciating more due to splitting of habitat ranges into more small isolated groups during
4230-759: A hundred years of systematic persecution by humans (from the early 1800s to around World War II ) followed by inadvertent poisonings and epidemics of nesting failures due to various manmade chemical pesticides and organic compounds , which have threatened eagles since roughly the 1950s and continue to be a potential concern. Due to this, the white-tailed eagle was considered endangered or extinct in several countries. Some populations have since recovered well, due to governmental protections, dedicated conservationists and naturalists protecting habitats and nesting sites, partially regulating poaching and pesticide usage, as well as careful reintroductions into parts of their former range. White-tailed eagles usually live most of
4465-405: A large range, a lack of individuals of both sexes (in sexually reproducing species), or other reasons. Pinpointing the extinction (or pseudoextinction ) of a species requires a clear definition of that species . If it is to be declared extinct, the species in question must be uniquely distinguishable from any ancestor or daughter species, and from any other closely related species. Extinction of
4700-592: A later point. The coelacanth , a fish related to lungfish and tetrapods , is an example of a Lazarus taxon that was known only from the fossil record and was considered to have been extinct since the end of the Cretaceous Period . In 1938, however, a living specimen was found off the Chalumna River (now Tyolomnqa) on the east coast of South Africa. Calliostoma bullatum , a species of deepwater sea snail originally described from fossils in 1844 proved to be
4935-420: A long time for them to dry. This may also make them vulnerable to losing their catch to other white-tailed eagles since their flight may be impaired until the wings are dried. Therefore, when hunting fish, they will fly to a feeding perch or nest as soon as possible most of the time. Another option when taking particularly large fish is for the eagle to stay in the water and row, swimming using their wings, across
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#17328838009325170-450: A longer and differently marked tail. At all ages, the white-tailed eagle averages a duller, slightly darker and browner colour overall than the Pallas's fish eagle. Pallas's fish eagles are mid-brown on the body in juvenile plumage with no paler feather edging as seen in juveniles and especially subadults of the larger species. Adult Pallas's fish eagles are immediately distinctive rufous hue with
5405-432: A lower yield, fish of up to 30 cm (12 in) are taken secondarily and fish between 30 and 60 cm (0.98 and 1.97 ft) are preferred since they have the highest nutritional benefit. Fish taken can exceed 0.9 to 1 m (3.0 to 3.3 ft) but since they can start to considerably exceed the weight of the eagle itself, they may prove too heavy to carry. One large Atlantic halibut ( Hippoglossus hippoglossus )
5640-648: A lowland species, the species is known to live at elevations of 1,500 to 2,300 m (4,900 to 7,500 ft) so long as there is water access in some parts of Central Asia and Siberia . In coastal areas, the species may range from high sea cliffs down to low-lying islands and archipelagos . Especially in winter, many white-tailed eagles often frequent low coastal spots, estuaries and coastal marshes . Several studies have supported that coastal areas are preferred when available during winter. In many areas, white-tailed eagles can seem to switch freely between usually cliff habitat and wooded spots for nesting sites and
5875-554: A majority staying near the Baltic coast. However, some eagles that hatched from nests in Germany have been found as far south as in Italy, 1,030 km (640 mi) away to the southeast, or to Gironde , France , 1,520 km (940 mi) to the southwest. In several parts of Russia, quite unlike many European populations, the white-tailed eagle seems to be largely migratory. In the far east,
6110-620: A mallard was caught while flying in mid-air, but usually the much larger eagle is unable to capture ducks in flight. While somewhat less swift in flight, healthy geese can usually outpace a heavier eagle as well and one bean goose ( Anser fabalis ) was even recorded to have defended itself successfully against an eagle's attack even though this goose was injured. White-tailed eagles often hunt dabbling ducks and geese most successfully when they are moulted into their eclipse plumage which renders them temporarily flightless. Swans during winter may find themselves forced to land due to their bulk on
6345-587: A mathematical model that falls in all positions. By contrast, conservation biology uses the extinction vortex model to classify extinctions by cause. When concerns about human extinction have been raised, for example in Sir Martin Rees ' 2003 book Our Final Hour , those concerns lie with the effects of climate change or technological disaster. Human-driven extinction started as humans migrated out of Africa more than 60,000 years ago. Currently, environmental groups and some governments are concerned with
6580-566: A more restricted but more sharply demarked paler buffy head. Bald eagle juveniles may be found together with white-tailed eagles in the Aleutian islands (where the white-tailed eagle formerly bred until about 30 years ago) and when vagrants of white-tails occur in Alaska. Juveniles of bald and white-tailed eagles often strongly resemble each other but the bald eagles have a shorter neck, a relatively longer and squarer tail, and somewhat less broad wings. In
6815-630: A much stronger preference for fish in Greenland by 1983, as fish comprised an extreme 91.8% of 660 items. However, this kind of direct continuous observation of food deliveries to nests is not always possible. Furthermore, despite similar bias for prey that is large and leaves conspicuous remains (including any larger fish, bird or mammal), in the bald eagle it was found that fish were usually detectable and dominant in remains and pellets. Most modern biologists may need to leave some fish unidentified but will account for different methodologies of prey study to get
7050-456: A natural part of the evolutionary process. Only recently have extinctions been recorded and scientists have become alarmed at the current high rate of extinctions . Most species that become extinct are never scientifically documented. Some scientists estimate that up to half of presently existing plant and animal species may become extinct by 2100. A 2018 report indicated that the phylogenetic diversity of 300 mammalian species erased during
7285-438: A nest is approached (usually recorded while directed towards humans). The young let out a monotonous veee-veee when hungry (or "bored") which intensifies if the eaglets are not fed or brooded immediately. Given reasonable view, adult white-tailed eagles are difficult to mistake for any other bird. There are no other eagles with fully white tails in their range except for in the easternmost limits of their range, their cousins
Haast's eagle - Misplaced Pages Continue
7520-441: A nest with some security. Although a relatively gregarious raptor, especially among wintering birds and juveniles and immature birds, they are territorial and intrusion by a male in adult plumage often provokes vigorous fighting, in which either combatant can even die. In some cases, these vicious fights can cause damage to the nest as the two fighting eagles plummet down trying to slash at each other. The white-tailed eagle's diet
7755-441: A new mega-predator or by transporting animals and plants from one part of the world to another. Such introductions have been occurring for thousands of years, sometimes intentionally (e.g. livestock released by sailors on islands as a future source of food) and sometimes accidentally (e.g. rats escaping from boats). In most cases, the introductions are unsuccessful, but when an invasive alien species does become established,
7990-610: A population a higher chance in the short term of surviving an adverse change in conditions. Effects that cause or reward a loss in genetic diversity can increase the chances of extinction of a species. Population bottlenecks can dramatically reduce genetic diversity by severely limiting the number of reproducing individuals and make inbreeding more frequent. Extinction sometimes results for species evolved to specific ecologies that are subjected to genetic pollution —i.e., uncontrolled hybridization , introgression and genetic swamping that lead to homogenization or out-competition from
8225-407: A race of animals to become extinct. A series of fossils were discovered in the late 17th century that appeared unlike any living species. As a result, the scientific community embarked on a voyage of creative rationalization, seeking to understand what had happened to these species within a framework that did not account for total extinction. In October 1686, Robert Hooke presented an impression of
8460-502: A reduction in agricultural productivity. Furthermore, increased erosion contributes to poorer water quality by elevating the levels of sediment and pollutants in rivers and streams. Habitat degradation through toxicity can kill off a species very rapidly, by killing all living members through contamination or sterilizing them. It can also occur over longer periods at lower toxicity levels by affecting life span, reproductive capacity, or competitiveness. Habitat degradation can also take
8695-425: A relatively smaller head. Young white-tailed eagles are also potentially confusable with any Aquila , but should be obvious even as a silhouette in its huge wings, relatively truncated and slightly wedge-shaped tail and obvious projection of the neck and head. All Aquila lack pale the axillary band often visible on juvenile and subadult white-tailed eagles. Some greater spotted eagles ( Clanga clanga ) can suggest
8930-486: A result of climate change has been confirmed by fossil studies. Particularly, the extinction of amphibians during the Carboniferous Rainforest Collapse , 305 million years ago. A 2003 review across 14 biodiversity research centers predicted that, because of climate change, 15–37% of land species would be "committed to extinction" by 2050. The ecologically rich areas that would potentially suffer
9165-499: A result of the bird hunting animals much larger than itself. Until recent human colonisation that introduced rodents and cats, the only placental land mammals found on the islands of New Zealand were three species of bat . Birds occupied or dominated all major niches in the New Zealand animal ecology . Moa were grazers, functionally similar to large ungulates , such as deer or cattle in other habitats, and Haast's eagles were
9400-431: A richer, more deeply dark brown (or somewhat rufescent ) than average with perhaps a mild increase in average darkness of hue to the east of the species' range. When many of the feathers are freshly moulted, they can take on a slight purplish gloss. The brownish hue of the adult overall makes the somewhat wedge-shaped white tail stand out in contrast. All the bare parts of the adult's body are yellow in colour, including
9635-523: A sheet of ice over water if they can find no open water, which can make their feet stuck to the ice. White-tailed eagles have been recorded utilizing this disability to attack and kill swans. They've also been seen to attack numerous waterfowl when the birds are injured by buckshot from duck hunters. Due to their status as enemy of other large birds, they are frequently mobbed by them and white-tailed eagles have been recorded utilizing violent mobbings to suddenly turn over in flight and predaceously grab one of
Haast's eagle - Misplaced Pages Continue
9870-416: A single meal upon capturing a large fish. The crop can bulge to the size of a small grapefruit after they've consumed a large meal. Many studies have reflected that the primary foods of white-tailed eagles are fish and water birds. These are the primary food as well for other sea eagle species. However, unlike most Haliaeetus , including the bald eagle and Steller's sea eagle, the water birds tend to take
10105-479: A species (or replacement by a daughter species) plays a key role in the punctuated equilibrium hypothesis of Stephen Jay Gould and Niles Eldredge . In ecology , extinction is sometimes used informally to refer to local extinction , in which a species ceases to exist in the chosen area of study, despite still existing elsewhere. Local extinctions may be made good by the reintroduction of individuals of that species taken from other locations; wolf reintroduction
10340-439: A species may come suddenly when an otherwise healthy species is wiped out completely, as when toxic pollution renders its entire habitat unliveable; or may occur gradually over thousands or millions of years, such as when a species gradually loses out in competition for food to better adapted competitors. Extinction may occur a long time after the events that set it in motion, a phenomenon known as extinction debt . Assessing
10575-404: A species or group of species. "Just as each species is unique", write Beverly and Stephen C. Stearns , "so is each extinction ... the causes for each are varied—some subtle and complex, others obvious and simple". Most simply, any species that cannot survive and reproduce in its environment and cannot move to a new environment where it can do so, dies out and becomes extinct. Extinction of
10810-436: A specimen from Greenland which measured 2.53 m (8 ft 4 in) while another specimen apparently spanned 2.6 m (8 ft 6 in). The bald eagle broadly overlaps in size with the white-tailed eagle. In direct comparison, the white-tailed eagle averages somewhat larger in body mass than the bald eagle and may be marginally larger in bill and talon size, although these linear aspects can be quite similar between
11045-518: A subsequent report, IPBES listed unsustainable fishing, hunting and logging as being some of the primary drivers of the global extinction crisis. In June 2019, one million species of plants and animals were at risk of extinction. At least 571 plant species have been lost since 1750, but likely many more. The main cause of the extinctions is the destruction of natural habitats by human activities, such as cutting down forests and converting land into fields for farming. A dagger symbol (†) placed next to
11280-451: A thousand eiders were taken here). Eiders also appeared to be the main prey species in Iceland. There is evidence that a growing white-tailed eagle population is having a net negative effect on eider numbers in some areas, and locally eiders have altered to partial nocturnal foraging apparently to avoid hunting eagles. In inland regions, an avian prey species preferred by white-tailed eagles
11515-489: A water depth of 1.5 to 2 m (4.9 to 6.6 ft). In addition to trees, they may also use crags , hillocks or high grassy tussocks as hunting perches so long as the perch provides a good overall view of the environment. Fish tend to be grabbed in a shallow dive after a short distance flight from a perch, usually with the eagles only getting their feet wet. Occasionally, though, white-tailed eagles have been recorded plunging right into water, usually while hunting on
11750-545: A white-headed (the bald eagle) and a tan-headed species. They probably diverged in the North Pacific , spreading westwards into Eurasia and eastwards into North America . Like the third large northern species, Steller's sea eagle ( Haliaeetus pelagicus ), adults have yellow feet, beaks and eyes. Another species, likely intermediate between the white-tailed, bald and Steller's sea eagles and the Ichthyophaga type fish eagles,
11985-549: A wingspan of 11.5 metres (38 ft) is constructed from stainless steel tube and sheet and was designed and constructed by Mark Hill, a sculptor from Arrowtown , New Zealand. The Haast's eagle also appeared in a 2003 BBC documentary Monsters We Met . There is also a statue depicting the Haast's eagle in Karamea , West Coast. This statue was unveiled by the community and the Ngāti Waewae iwi. Extinction Extinction
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#173288380093212220-435: Is 250 to 331 mm (9.8 to 13.0 in) in males, averaging 280 mm (11 in), and 276 to 330 mm (10.9 to 13.0 in) in females, averaging 305 mm (12.0 in). Juvenile tail lengths can reach roughly 380 mm (15 in) in both sexes, however. The tarsus is 90 to 101 mm (3.5 to 4.0 in), averaging 95.5 mm (3.76 in). In terms of their killing apparatuses, their hallux claw ,
12455-454: Is a relatively weak and ponderous flier and so too may be often victimized by the eagles. Otherwise the pale plumage of adult male common eiders while they're diving is reported to make them more vulnerable to eagle attacks. Eiders were the leading prey species in Norway making 18.8% of 1612 prey items, as well as in Åland , Finland where the eider comprised 18.63% of 5161 prey items (thus nearly
12690-517: Is also evidence to suggest that this event was preceded by another mass extinction, known as Olson's Extinction . The Cretaceous–Paleogene extinction event (K–Pg) occurred 66 million years ago, at the end of the Cretaceous period; it is best known for having wiped out non-avian dinosaurs , among many other species. According to a 1998 survey of 400 biologists conducted by New York 's American Museum of Natural History , nearly 70% believed that
12925-444: Is an example of this. Species that are not globally extinct are termed extant . Those species that are extant, yet are threatened with extinction, are referred to as threatened or endangered species . Currently, an important aspect of extinction is human attempts to preserve critically endangered species. These are reflected by the creation of the conservation status "extinct in the wild" (EW) . Species listed under this status by
13160-587: Is considered rare. Nonetheless, they have been recorded eating a few eggs, which they may carry in their beaks rather in their feet, of some seabirds such as kittiwakes , eiders , cormorants and gulls. The most widely recorded avian prey species and, second most widely recorded prey species behind the pike, is the 1.14 kg (2.5 lb) mallard, due to its circumpolar range and commonality in many wetlands areas. However, as aforementioned, healthy mallards are difficult for white-tailed eagles due to their tendency to fly at first sign of danger. However, exploiting
13395-555: Is correct, its increase in weight by ten to fifteen times is an exceptionally rapid weight increase. The suggested increase in the average weight of Haast's eagle over that period would therefore represent the largest, fastest evolutionary increase in average weight of any known vertebrate species. This was made possible in part by the presence of large prey and the absence of competition from other large predators, an example of ecological release and island gigantism . A recent mitochondrial DNA study found it to be more closely related to
13630-585: Is difficult to demonstrate unless one has a strong chain of evidence linking a living species to members of a pre-existing species. For example, it is sometimes claimed that the extinct Hyracotherium , which was an early horse that shares a common ancestor with the modern horse , is pseudoextinct, rather than extinct, because there are several extant species of Equus , including zebra and donkey ; however, as fossil species typically leave no genetic material behind, one cannot say whether Hyracotherium evolved into more modern horse species or merely evolved from
13865-511: Is equivalent to about 10% of the birds' body weight, with crop contents commonly of 190–560 g (0.42–1.23 lb). Some semi-captive juveniles on the isle of Rùm , Scotland could eat up to 1.4 kg (3.1 lb) in one sitting. However, in Norway, it was estimated that a family of wild white-tailed eagles including each adult and three fledglings were consuming on average up to 625 g (1.378 lb) per bird each day. Furthermore, one male consumed an estimated 2 kg (4.4 lb) in
14100-417: Is estimated as 100 to 1,000 times "background" rates (the average extinction rates in the evolutionary time scale of planet Earth), faster than at any other time in human history, while future rates are likely 10,000 times higher. However, some groups are going extinct much faster. Biologists Paul R. Ehrlich and Stuart Pimm , among others, contend that human population growth and overconsumption are
14335-563: Is explained as an evolutionary response to the size of its prey —the flightless moa —the largest of which could weigh 200 kg (440 lb). Haast's eagle became extinct around 1445, following the arrival of the Māori , who hunted moa to extinction, introduced the Polynesian rat ( Rattus exulans ), and destroyed large tracts of forest by fire. Haast's eagle was first scientifically described by Julius von Haast in 1871 from remains discovered by
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#173288380093214570-442: Is in short supply. White-tailed eagles of all ages typically perch in quite upright positions on exposed branch, rock or other vantage point, but tend to sit more horizontally on the ground or other level surfaces. They have an ample bill with a relatively high culmen, helping to impart a rather narrow and high crowned facial look, especially compared to Aquila eagles . The neck is at times unusually long-looking, more so than in
14805-435: Is known as the ern or erne (depending on spelling by sources), gray sea eagle and Eurasian sea eagle . While found across a wide range, today breeding from as far west as Greenland and Iceland across to as far east as Hokkaido , Japan , they are often scarce and spottily distributed as a nesting species, mainly due to human activities. These have included habitat alterations and destruction of wetlands , about
15040-487: Is known at this age. However, this white mottling then fades late into the fourth year and the plumage becomes less contrasting. Although sexual maturity is considered to be attained at between five and six years of age, usually the fully white tail and the uniform pale head and neck are not obtained until the eighth year. Juveniles first moult in May/June until October/November at just over one year of age. Their second moult
15275-435: Is known in well more than half of all modern birds, essentially all predatory birds of different lineages are particularly strongly territorial because the live prey necessary to feed a family, including the female of the pair (which must remain near the young for them to survive) and the young themselves, tends to be sparser. Furthermore, appropriate habitat is needed in which to execute this hunting and also, of course, to build
15510-456: Is poor. Also, they will alternate periods of soaring with perching, especially flying over water or well-watered areas, but do considerably less soaring on average than do golden eagles. Pairs regularly roost together, often near to their nest, either on a crag or tree or crevices, overhung ledges or small isolated trees on a crag. The white-tailed eagle may be considered a rather inconsistent and partial migrant. The species seldom migrates in
15745-590: Is the Pallas's fish eagle ( Haliaeetus leucoryphus ), which in life history seems to range farther from water and to higher elevations than the three northern species normally do. Due to the similar dietary and nesting habits of sea eagles, they are mostly allopatric in distribution as competition can be considerable between these eagles. Currently, eagles occur in the Hawaiian Islands only as vagrants, but Quaternary bones of Haliaeetus have been found on three of
15980-795: Is the common bream ( Abramis brama ). This bream was reported in 10 of 18 dietary studies and was the main prey in the Polesie State Radioecological Reserve , Belarus, in the Ural mountains region of Russia, and in the Kostomuksha Nature Reserve , Russia. Breams taken by reeding eagles at Augustów Forest , Poland ranged from 0.2 to 2 kg (0.44 to 4.41 lb) in weight. Many varieties of fish are taken opportunistically and randomly, as opposed to pike and bream, which can locally appear to be selected out of proportion to their regional population. Particularly diverse in
16215-599: Is the 836 g (1.843 lb) Eurasian coot ( Fulica atra ). The coot is the second most widely represented bird prey species (and fourth species of any class known overall) in 18 dietary studies. Coots bunch together in marshy spots when approached by a flying eagle and as many as five eagles at once have been recorded attacking large flocks on the water. Coots' behaviour often endangers them to large raptors: they seldom dive, are weaker and slower fliers than most water birds and are collectively often less wary and more approachable than most waterfowl are. Coot were strongly
16450-592: Is the destruction of ocean floors by bottom trawling . Diminished resources or introduction of new competitor species also often accompany habitat degradation. Global warming has allowed some species to expand their range, bringing competition to other species that previously occupied that area. Sometimes these new competitors are predators and directly affect prey species, while at other times they may merely outcompete vulnerable species for limited resources. Vital resources including water and food can also be limited during habitat degradation, leading to extinction. In
16685-448: Is the following year in March or April, with two more subsequent moults usually beginning around this time for the next couple of years. Like other large raptors, feathers are moulted at slow intervals so as not to inhibit food capture. Only relatively small proportions of the flight feathers are moulted each year. Moulting occurs more or less continuously, although it may pause in winter if food
16920-525: Is the most important determinant of genus extinction at background rates but becomes increasingly irrelevant as mass extinction arises. Limited geographic range is a cause both of small population size and of greater vulnerability to local environmental catastrophes. Extinction rates can be affected not just by population size, but by any factor that affects evolvability , including balancing selection , cryptic genetic variation , phenotypic plasticity , and robustness . A diverse or deep gene pool gives
17155-457: Is the termination of a taxon by the death of its last member . A taxon may become functionally extinct before the death of its last member if it loses the capacity to reproduce and recover. Because a species' potential range may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such as Lazarus taxa , where a species presumed extinct abruptly "reappears" (typically in
17390-461: Is typically large as in all Haliaeetus , ranging from 45 to 65 mm (1.8 to 2.6 in), with an average of 56.1 mm (2.21 in). The average culmen length of the bald eagle is 54.3 mm (2.14 in), thus averaging slightly smaller. However, the average culmen length in the large bald eagles of Alaska is considerably larger than other bald eagles as well as most white-tailed eagles at up to 75 mm (3.0 in) and can even rival
17625-435: Is usually more evident in flying than perched birds, with sometimes a slightly bulging section of feathers manifesting on the wing secondaries . The species tends to fly with shallow wing beats; at times the wing beats can be fairly fast for a bird of this size, but interspersed at times with gliding. At a great distance, this flight style may be suggestive of a large brown heron . The wings are held flat or slightly upraised at
17860-404: Is varied, opportunistic and seasonal. Prey specimens can often include fish, birds and, mostly in a secondary capacity, mammals. White-tailed eagles are powerful predators and capable of attacking large prey of considerable sizes but, like most predators, prefer prey that is vulnerable and easy for them to capture. Especially during the winter (and opportunistically in all seasons), many birds of
18095-474: The Description de l'Égypte . The name Haliaeetus is Neo-Latin for "sea-eagle", from Ancient Greek hali- , "sea-" and aetos , "eagle". The specific albicilla , "white-tailed", is from Neo-Latin albi- , "white" and cilla , "tail". The Anglo-Saxon name erne means "soarer", and it is cognate to Swedish örn and Finnish aarni . It has many Gaelic names, including iolar sùil na grèine or 'eagle of
18330-688: The Baltic Sea , western Austria , northeastern Germany , northern and eastern Poland , the Czech Republic, much of the east Baltic countries , the non-montane areas of Ukraine , eastern Slovenia , central and southern Hungary (and adjacent northeastern Croatia ), sporadically in Greece , the Danube sections of Romania and Bulgaria to the Black Sea and western and eastern Moldova . The bird returned to
18565-520: The Brahminy kite ( Haliastur indus ) (historically sometimes referred to as the "red-backed sea eagle") and the palm-nut vulture ( Gypohierax angolensis ) (which was once widely referred to as the "vulturine fish eagle"). The relation of these species to the sea eagles is partially borne out by their genetic sequencing. Other groups, beyond milvine kites and Old World vulture, of modern accipitrids that are seemingly in some way related, albeit distantly, to
18800-565: The Canterbury Museum taxidermist, Frederick Richardson Fuller, in a former marsh. Haast named the eagle Harpagornis moorei after George Henry Moore , the owner of the Glenmark Estate, where the bones of the bird were found. The genus name was from the Greek harpax , meaning "grappling hook", and ornis , meaning "bird". DNA analysis later showed that this bird is related most closely to
19035-588: The Griffon vulture ( Gys fulvus ), as the colouring of the two species is vaguely similar and they can overlap somewhat in size although the vulture can average rather heavier and longer winged. However even at long range, the relatively tiny head, distinctly curved trailing wing-edges and more raised wings make the vulture distinctive from the white-tailed eagle. Juveniles may be harder to distinguish, mainly from other sea eagles in few areas of overlap. In northern Mongolia (perhaps spilling over into southern Siberia ),
19270-474: The International Union for Conservation of Nature (IUCN) are not known to have any living specimens in the wild and are maintained only in zoos or other artificial environments. Some of these species are functionally extinct, as they are no longer part of their natural habitat and it is unlikely the species will ever be restored to the wild. When possible, modern zoological institutions try to maintain
19505-477: The Late Pleistocene could take up to 5 to 7 million years to restore mammal diversity to what it was before the human era. Extinction of a parent species where daughter species or subspecies are still extant is called pseudoextinction or phyletic extinction. Effectively, the old taxon vanishes, transformed ( anagenesis ) into a successor, or split into more than one ( cladogenesis ). Pseudoextinction
19740-502: The Levant countries, Azerbaijan and Iran down to even the Persian Gulf , albeit seldom is the species to be found commonly or reliably anywhere in these regions. Further east, rare wintering areas are known in a few small, scarce pockets of Turkmenistan, Afghanistan , Uzbekistan , Tajikistan and Pakistan . It is a rare winter visitor to India , namely the extreme northwest and along
19975-675: The Middle East , the white-tailed eagle may still be found breeding only along the southern coast of the Caspian Sea in northern Iran and southwestern Turkmenistan . Discontinuously, they are found as residents in Kazakhstan where they live in a long strip of the southern part of the country starting at the Aral Sea and the northwestern portion (but not, as far as is known, breeding in the Kazakh part of
20210-500: The Māori mythology , under the names pouākai , Hakawai (or Hōkioi in the North Island ). According to an account given to Sir George Grey —an early governor of New Zealand—Hōkioi were huge black-and-white birds with yellow-green tinged wings and a red crest . In Māori mythology, Pouākai would prey and kill humans along with moa, which scientists believe could have been possible if
20445-582: The Netherlands in 2006 and in 2020 the number of breeding pairs had increased to 20. It might have bred in the Faroe Islands up until the 17th century, but evidence is lacking; there are only about a dozen records of vagrant white-tailed eagles from the archipelago since 1800. In Anatolia , it only remains as a breeder in sparse and small pockets of Turkey and Georgia , taken as a region there are likely to be fewer than 30 breeding pairs in this region. In
20680-593: The Philippine eagle ( Pithecophaga jefferyi ), and the Steller's sea eagle are the largest and most powerful living eagles, and the first two also have a similarly reduced relative wing-length as an adaptation to forest-dwelling. A lower mandible from the Haast's eagle measured 11.4 cm ( 4 + 1 ⁄ 2 in) and the tarsus in several Haast's eagle fossils has been measured from 13.7 to 16.2 cm ( 5 + 3 ⁄ 8 to 6 + 3 ⁄ 8 in). In comparison,
20915-607: The Wigry National Park , Poland,1,062.1 g (2.342 lb) in the Rybinsk Reservoir , Russia and 1.72 kg (3.8 lb) in the Volga-Kama Nature Reserve , Russia. Thus, the mean prey size falls just slightly short of the mean prey mass of the golden eagle, which globally averages about 1.35 to 1.63 kg (3.0 to 3.6 lb). Overall, nearly 70 species of fish are known to be taken from throughout
21150-601: The alluvial wetlands of Croatia, 95% of nests were found within 4 km (2.5 mi) of deep freshwater. In some areas, white-tailed eagles readily visit commercial fish farms , carp ponds and similar areas with easily accessible food but they will usually avoid areas where human disturbances (especially noisy varieties such as construction , water sporting and heavy boating activities and hunting ) commonly occur. However, forestry activity and resulting lessened numbers of tall mature trees and large tree stands in Estonia
21385-429: The common lumpsucker ( Cyclopterus lumpus ), which averages up to 1.43 kg (3.2 lb) but is usually smaller, made up 24% of fish taken and the 2.13 kg (4.7 lb) Atlantic wolffish ( Anarhichas lupus ) made up 17% of fish taken. However, fish were secondary to birds overall in Norway. Per two studies from Sweden, fish were usually the main food unlike in Norway and Finland, and could comprise 51–60% of
21620-619: The fossil record ) after a period of apparent absence. More than 99% of all species that ever lived on Earth , amounting to over five billion species, are estimated to have died out. It is estimated that there are currently around 8.7 million species of eukaryotes globally, and possibly many times more if microorganisms , such as bacteria , are included. Notable extinct animal species include non-avian dinosaurs , saber-toothed cats , dodos , mammoths , ground sloths , thylacines , trilobites , golden toads , and passenger pigeons . Through evolution , species arise through
21855-410: The slender-billed curlew ( Numenius tenuirostris ), not seen since 2007. As long as species have been evolving, species have been going extinct. It is estimated that over 99.9% of all species that ever lived are extinct. The average lifespan of a species is 1–10 million years, although this varies widely between taxa. A variety of causes can contribute directly or indirectly to the extinction of
22090-484: The strata of the Paris basin. They saw alternating saltwater and freshwater deposits, as well as patterns of the appearance and disappearance of fossils throughout the record. From these patterns, Cuvier inferred historic cycles of catastrophic flooding, extinction, and repopulation of the earth with new species. Cuvier's fossil evidence showed that very different life forms existed in the past than those that exist today,
22325-410: The waterfowl favoured in the avian diet tend to be highly wary and will more often than not escape. The white-tailed eagles must then attack birds at times of vulnerability or injury, or will often utilize the prey's escape tactics against them. Diving ducks and other diving water birds will be taken preferentially where they are available. In hunting diving birds, they utilize a technique of forcing
22560-523: The white-bellied sea eagle juvenile, likely a closely related species) more typical of juveniles in other species and it also dwells more so in dense, coastal forests where it feeds mostly on birds and mammals rather than fish and water birds . Outside of the genus Haliaeetus , among other extant forms, they appear to be most closely related to milvine kites and Old World vultures , based on modern forms from these subfamilies that broadly share morphological and life history traits with sea eagles:
22795-421: The ' sea eagle ', is a large bird of prey, widely distributed across temperate Eurasia . Like all eagles, it is a member of the family Accipitridae (or accipitrids) which also includes other diurnal raptors such as hawks , kites , and harriers . One of up to eleven members in the genus Haliaeetus , which are commonly called sea eagles, it is also referred to as the white-tailed sea-eagle . Sometimes, it
23030-656: The 1.23 kg (2.7 lb) red-breasted goose ( Branta ruficollis ) to the non-native 3.69 kg (8.1 lb) Canada goose ( Branta canadensis ). Goslings and juveniles are usually targeted, but adult geese are also taken, especially while incubating or weakened by various reasons. Another large water bird taken as adults are 4.98 kg (11.0 lb) common loons ( Gavia immer ). Large waders are taken when possible, including grey herons and great bitterns ( Botaurus stellaris ), both weighing between 1 and 2 kg ( 2 + 1 ⁄ 4 and 4 + 1 ⁄ 2 lb). Larger 2.93 kg (6.5 lb) black and
23265-445: The 1979 study, 68% of the diet would have been represented by birds and only 20% by fish but comprehensive observation shifted it to show fish were the primary food at 58% and birds were secondary at 30%. This study claimed this is often because the bones of fish are dissolved by the large digestive tract of the eagles upon consumption and may thus leave almost nothing in remains and to some extent in pellets. Subsequent studies here showed
23500-619: The 20 biodiversity goals laid out by the Aichi Biodiversity Targets in 2010, only 6 were "partially achieved" by the deadline of 2020. The report warned that biodiversity will continue to decline if the status quo is not changed, in particular the "currently unsustainable patterns of production and consumption, population growth and technological developments". In a 2021 report published in the journal Frontiers in Conservation Science , some top scientists asserted that even if
23735-667: The 3.44 kg (7.6 lb) white stork ( Ciconia ciconia ) of all ages can be preyed upon. Black and white storks are the primary prey species in the Polesie State Radioecological Reserve, Belarus, where they comprised 12.6% (second most regular prey species) and 6.3% (fourth most regular) of the diet, respectively. Large numbers of black storks were also taken in Augustów Primeval Forest where remains of nearly 50 individuals were found around eagle nests. White-tailed eagles even attack and prey on both
23970-451: The Aichi Biodiversity Targets set for 2020 had been achieved, it would not have resulted in a significant mitigation of biodiversity loss. They added that failure of the global community to reach these targets is hardly surprising given that biodiversity loss is "nowhere close to the top of any country's priorities, trailing far behind other concerns such as employment, healthcare, economic growth, or currency stability." For much of history,
24205-539: The Black Sea which have been recorded 330 km (210 mi) north of their natal site and 510 km (320 mi) northeast of their natal site. Territory size in white-tailed eagles may vary from 52 to 415 km (20 to 160 sq mi), usually less than 130 km (50 sq mi), per one estimate. However, home ranges in northeastern Germany were much smaller than this, at 2.25 to 19.16 km (0.87 to 7.40 sq mi). While territorial behaviour
24440-529: The Caspian Sea coast). The only country in which the white-tailed eagle is found over a continuous and extremely large area is Russia . The species is found broadly everywhere in Russia from European Russia in the west to the Bering Sea in the east, only being fully absent as a nester as far as is known from the high Arctic regions and a section bordering westernmost Kazakhstan, although it breeds to south of this in
24675-605: The Earth is currently in the early stages of a human-caused mass extinction, known as the Holocene extinction . In that survey, the same proportion of respondents agreed with the prediction that up to 20% of all living populations could become extinct within 30 years (by 2028). A 2014 special edition of Science declared there is widespread consensus on the issue of human-driven mass species extinctions. A 2020 study published in PNAS stated that
24910-404: The Haast's eagle with a pale head. These Māori rock art drawings can still be found in modern-day South Canterbury near Timaru . Combined with its vulture-like feeding behaviour, this might suggest it had a bald head, or had shorter feathers on its head than elsewhere on its body. The Haast's eagle predominantly preyed on large, flightless bird species, including the moa, which ultimately led to
25145-518: The Hawaiian mtDNA lineage probably diverged around the Middle Pleistocene. Thus, although not clearly differentiated in morphology from its relatives, the Hawaiian eagle likely represented an isolated, resident population in the Hawaiian archipelago for more than 100,000 years, where it was the largest terrestrial predator. The reasons for its extinction are unknown. The white-tailed eagle is one of
25380-594: The Netherlands, even with infrequent modern breeding in the northern coastal areas. A wintering population is known in western Germany from North Rhine-Westphalia to Bonn , as well as far northern Germany. In Denmark, they both breed and winter throughout much of the country, but in particular the Wadden Sea region attracts many white-tailed eagles, mostly immatures, from elsewhere in Denmark and neighbouring countries during
25615-570: The North American moose and that the animal had once been common on the British Isles . Rather than suggest that this indicated the possibility of species going extinct, he argued that although organisms could become locally extinct, they could never be entirely lost and would continue to exist in some unknown region of the globe. The antlers were later confirmed to be from the extinct deer Megaloceros . Hooke and Molyneux's line of thinking
25850-518: The Paris basin, could be formed by a slow rise and fall of sea levels . The concept of extinction was integral to Charles Darwin 's On the Origin of Species , with less fit lineages disappearing over time. For Darwin, extinction was a constant side effect of competition . Because of the wide reach of On the Origin of Species , it was widely accepted that extinction occurred gradually and evenly (a concept now referred to as background extinction ). It
26085-876: The Russian Far East are known to occasionally disperse across the Bering Sea to North America in several parts of the Aleutian Islands , the Pribilof Islands and some of mainland coastal Alaska down to Kodiak Island . Some white-tailed eagles even bred in Alaska on Attu Island in the late 1970s to the early 1980s (until 1984 when the last attempts were recorded) but it was not clear whether young were ever successfully fledged. White-tailed eagles may be found in varied habitat but usually are closely associated with water and generally occurs in lowland areas. Although mainly
26320-867: The Russian coastal part of the Caspian Sea. Their northern limits occur in Russia to the Ob river to 70 degrees north at the mouth of the Yenisei River and on the Gyda and Yamal Peninsulas , to the Kolyma , Indigirka and Lena rivers to above 72 degrees north, even to 75 degrees north on the Taymyr Peninsula . They are said to be common around the White Sea , reportedly even the most abundant bird of prey locally and found both on coasts and inland lakes, although breeding rates are low due to
26555-560: The Scandinavian countries, up to at least 30–50 individuals. Wintering congregations at the Baltic coast and on the River Elbe from 37 winters show that arrivals begin in November, with numbers peaking in January and then declining during March and early April. Although juveniles usually return to their natal area some apparently overshoot these areas, such as those returning to Romania or on
26790-462: The Steller's sea eagle may rival it in that respect. In one sample from Norway , five male white-tailed eagles were found to average 2.26 m (7 ft 5 in) and eight females were found to average 2.37 m (7 ft 9 in). In another sample of wild birds of unspecified origin, five males were found to average 2.1 m (6 ft 11 in) and seven females averaged 2.3 m (7 ft 7 in). Record wingspans have included
27025-477: The United States government, to force the removal of Native Americans , many of whom relied on the bison for food. White-tailed eagle Falco albicilla Linnaeus, 1758 Falco melanaetos Linnaeus, 1766 Falco ossifragus Linnaeus, 1766 Haliaeetus albicilla albicilla Haliaeetus albicilla groenlandicus The white-tailed eagle ( Haliaeetus albicilla ), sometimes known as
27260-488: The White Sea were found well over 2,000 km (1,200 mi) away to the west, in countries such as Hungary and Italy. Return spring migration to the White Sea is by February–March. During winter, whether long-distance migrants or short-distance dispersers, white-tailed eagles tend to become gregarious, especially younger immature birds. Many such groups can contain up to 10 and, in areas near large breeding populations such as
27495-429: The accumulation of slightly deleterious mutations , then a population will go extinct. Smaller populations have fewer beneficial mutations entering the population each generation, slowing adaptation. It is also easier for slightly deleterious mutations to fix in small populations; the resulting positive feedback loop between small population size and low fitness can cause mutational meltdown . Limited geographic range
27730-537: The adults, although the juveniles typically have a somewhat larger average wing and tail length than the adults. In the white-tailed eagle, body mass can typically range from 4 to 6.9 kg (8.8 to 15.2 lb) in females. The slightly smaller male may typically weigh from 3.1 to 5.4 kg (6.8 to 11.9 lb). Average weights in European white-tailed eagles can range from 4.02 kg (8.9 lb) in five males and 5.11 kg (11.3 lb) in nine females to (from
27965-556: The aforementioned water birds are modest of size and taken largely due to ease (diving water birds, whether healthy or infirm, and usually infirm or moulting dabbling water birds), white-tailed eagles routinely attack larger water birds as well. In many areas, large numbers of greylag geese ( Anser anser ), Europe's largest native wild goose, are taken. For example, they were the main prey, making up 28.2% of 192 prey items, for wintering eagles in Oostvaardersplassen , Netherlands, and
28200-513: The average female white-tailed eagle (the average weight of male Steller's is not known) while the average European golden eagle may weigh about 11–12% less than the average European white-tailed eagle and the bald eagle species as a whole about 10% less than the white-tailed eagle species. The most reliable method to sex birds is by tarsus width and depth and bill depth but these are infrequently measured. In some cases females are as much as 25% heavier and 15% greater in linear dimensions, though
28435-416: The bald eagle and Steller's sea eagle, which in adults are different in all other respects of plumage. Even in poor light, the bald species shows a sharp demarcation from white to dark brown whereas the colour contrast is far subtler in white-tailed eagles between their brown body (of a paler hue than that of a bald eagle) and buff-coloured head. At a great distance, the adult may be potentially confusable with
28670-448: The bald eagle, which can give the upper body a vulturine appearance. The tail is relatively short, and in some adults it can appear disproportionately stubby in relation to the massive body, and slightly wedge-shaped. All ages have a well-feathered tibia but bare tarsi . In flight, the wings are extremely broad and deeply fingered, with the usual tendency for at least six fingers to be visible. Juveniles are longer tailed than adults, which
28905-502: The bill of the Haast's eagle was functionally closer to that of the Andean condor ( Vultur gryphus ) than to that of other eagles. This is also supported by historic Māori Cave art which depicts the Haast's eagle being pale-headed. It also suggests that it deployed feeding tactics more similar to those of vultures after making a kill, plunging its head into the body cavity to devour the vital organs of its prey. This may have been an adaptation as
29140-457: The bill, cere , feet and eyes. Juvenile and immature white-tailed eagles are a much darker brown than the adults and are more unevenly marked, with whitish feather edgings variably showing, mostly manifesting in some small areas of the underside and under-wing, with a narrow white axillary strip usually apparent. The upperside is usually similarly darkish brown but variable based on extent of blackish-brown tip to otherwise buff-brown feathers of
29375-622: The birds mobbing them, including large gulls and even a northern goshawk ( Accipiter gentilis ). As an opportunistic predator, it often takes young birds freely as well as adult and fledged juvenile birds. In general, due to different nesting situations, white-tailed eagles instead of dabbling or diving water birds usually attack the more conspicuous or open nests of gulls, those of several other types of seabird , large corvids or other accipitrids. In Germany and Scotland, up to 86% of gulls taken were nestlings and juveniles. Cases of white-tailed eagles eating eggs, instead of nestlings or older birds,
29610-784: The birds to dive repeatedly to avoid attacks, until the victim is exhausted from the efforts and can then be caught. Usually while hunting like this, the white-tailed eagle tends to circle low to stay close to the intended victim, with birds diving in shallower water being preferred. Ducks with conspicuous plumage, such as male common eiders ( Somateria mollissima ), with their pale plumage, may be easier to see under water and so may be taken somewhat more via this hunting method. Beyond waterfowl, both loons and grebes have been seen to be successfully hunted in this way. Eagles were recorded doing up to 12 attacks on eiders in Russia and were usually successful in procuring prey. Even as many as 65 passes have recorded in less than 45 minutes but more than
29845-522: The birds to take off with a jumping start from the ground, despite their great weight. The tail was almost certainly long, in excess of 50 cm (20 in) in female specimens, and very broad. This characteristic would compensate for the reduction in wing area by providing additional lift . Total length is estimated to have been up to 1.4 m (4 ft 7 in) in females, with a standing height of approximately 90 cm (2 ft 11 in) tall or perhaps slightly greater. Māori cave art depicts
30080-421: The border of Nepal to Bhutan and extreme northern Bangladesh . Scattered pockets of wintering birds are known to occur too in central and southern China , into northeastern Myanmar , and more broadly and regularly in much of Northeast China. Good numbers winter too in much of South Korea and Japan down to as far as Honshu . White-tailed eagles dispersing from their breeding grounds or natal sites in
30315-466: The center of their home range habitat. In some areas, such as Japan, this species may occur in regions with intensive human fishing activity and they may become unusually partially habituated to this human presence. Inland, white-tailed eagles usually require secluded woods, forested areas or groups of trees with tall mature trees and access to freshwater wetlands such as lakes , river systems , marshes or extensive, low-disturbance farmland . In
30550-534: The colder months, especially in coastal areas such as Norway when preferred fish prey often move to deeper water during winter. Among both fish and bird prey, it is thought that a majority that are caught weigh between 0.5 and 3 kg (1.1 and 6.6 lb). At times it has been said that "most" prey of white-tailed eagles will weigh only 0.5 to 1 kg (1.1 to 2.2 lb). However, the mean prey sizes caught can show greater variability. Three studies showed that mean prey size varied from 578 g (1.274 lb) in
30785-428: The colouring, the bald juvenile is similarly as dark or even darker brown above as white-tailed eagle juveniles but on the underside often has more extensive whitish mottling, especially on the underwing. Steller's sea eagles are usually distinctly larger and longer tailed, with a taller, bulkier look in eagles standing on the ground or perched. Steller's juveniles have a different wing shape (roughly paddle-shaped) and
31020-600: The consequences can be catastrophic. Invasive alien species can affect native species directly by eating them, competing with them, and introducing pathogens or parasites that sicken or kill them; or indirectly by destroying or degrading their habitat. Human populations may themselves act as invasive predators. According to the "overkill hypothesis", the swift extinction of the megafauna in areas such as Australia (40,000 years before present), North and South America (12,000 years before present), Madagascar , Hawaii (AD 300–1000), and New Zealand (AD 1300–1500), resulted from
31255-418: The contemporary extinction crisis "may be the most serious environmental threat to the persistence of civilization, because it is irreversible." Biologist E. O. Wilson estimated in 2002 that if current rates of human destruction of the biosphere continue, one-half of all plant and animal species of life on earth will be extinct in 100 years. More significantly, the current rate of global species extinctions
31490-471: The deliberate destruction of some species, such as dangerous viruses , and the total destruction of other problematic species has been suggested. Other species were deliberately driven to extinction, or nearly so, due to poaching or because they were "undesirable", or to push for other human agendas. One example was the near extinction of the American bison , which was nearly wiped out by mass hunts sanctioned by
31725-558: The diet. Fish were also somewhat dominant in the foods from two studies in Belarus, making up 48.1–53.7% of the diet. Fish similarly were important to nesting eagles in Hokkaido, Japan where 54% of 533 prey items were fish, led by the 800 g (1.8 lb) Alaska pollock ( Gadus chalcogrammus ) at 18.4%. In different studies of the Danube Delta of Romania, from 44.6% to 79% of the diet
31960-447: The distinction of a subspecies. However, the population appears to be demographically isolated and deserves special protection. At one time an eastern subspecies ( H. a. brooksi ) was proposed as well but there is little evidence supporting this as more than a case of clinal variation in colouring and size (i.e. the eastern average slightly darker and smaller than more westerly ones). As in other sea-eagle species pairs, this one consists of
32195-1198: The dominant food in Wigry National Park, Poland where they made up 44.1% of 299 items, and were also the leading prey in Augustów Primeval Forest (Poland) where they made up 11.59% of the foods. Overall at Wigry and Augustów, birds altogether made up 66.2% and 47.83% of the diets, respectively. In the Danube Delta, Romania, birds climbed in importance of the diet from 21% in 1970 to 50% by 2015, thanks largely to increased numbers of coots. In total, about 38 species of waterfowl are known to be hunted, as well as all available species of loons and grebes, several types of rails , tubenoses as well as herons , storks and other assorted large waders. White-tailed eagles also are known to hunt some 42 species of shorebird , most significantly gulls and alcids . Even shorebirds as small as 21.1 g (0.74 oz) little stint ( Calidris minuta ), 62.6 g (2.21 oz) wood sandpiper ( Tringa glareola ) and 64 g (2.3 oz) common ringed plover ( Charadrius hiaticula ) are known to be preyed upon, albeit quite rarely. More than
32430-403: The endangered wild water buffalo is most threatened with extinction by genetic pollution from the abundant domestic water buffalo ). Such extinctions are not always apparent from morphological (non-genetic) observations. Some degree of gene flow is a normal evolutionary process; nevertheless, hybridization (with or without introgression) threatens rare species' existence. The gene pool of
32665-575: The event of rediscovery would be considered Lazarus species. Examples include the thylacine , or Tasmanian tiger ( Thylacinus cynocephalus ), the last known example of which died in Hobart Zoo in Tasmania in 1936; the Japanese wolf ( Canis lupus hodophilax ), last sighted over 100 years ago; the American ivory-billed woodpecker ( Campephilus principalis ), with the last universally accepted sighting in 1944; and
32900-443: The extinction crisis. According to the International Union for Conservation of Nature (IUCN), 784 extinctions have been recorded since the year 1500, the arbitrary date selected to define "recent" extinctions, up to the year 2004; with many more likely to have gone unnoticed. Several species have also been listed as extinct since 2004. If adaptation increasing population fitness is slower than environmental degradation plus
33135-475: The extinction of species caused by humanity, and they try to prevent further extinctions through a variety of conservation programs. Humans can cause extinction of a species through overharvesting , pollution , habitat destruction , introduction of invasive species (such as new predators and food competitors ), overhunting, and other influences. Explosive, unsustainable human population growth and increasing per capita consumption are essential drivers of
33370-403: The female when receiving food from male calls out with tschie-tschie or vueee-vueee . Single or repeated krlee or similar component of calls used in other circumstances, can be variable. Alarm calls tend to be 3–4 short, loud klee or klek notes. Sometimes a different call of alarm or anger, a deep gah-gah-gah or jok-jok-jok , similar to alarm calls of a large gull , is also uttered when
33605-533: The field of zoology , and biology in general, and has also become an area of concern outside the scientific community. A number of organizations, such as the Worldwide Fund for Nature , have been created with the goal of preserving species from extinction. Governments have attempted, through enacting laws, to avoid habitat destruction, agricultural over-harvesting, and pollution . While many human-caused extinctions have been accidental, humans have also engaged in
33840-500: The fish prey will float to the surface when infected by fish tapeworm , as is often the case with some fish families such as carp . Fish are also caught after being battered, injured, and killed at power plants, from large-scale fishing nets, or are taken directly from human fishermen. Benthic fish which tend to cling to rocks or sandy soil in shallows may be more vulnerable since they tend to look downward rather than upward and are less competent at escaping predators coming from above
34075-456: The flight of predators and may even kill some intended predators when it is in large quantity, and young juvenile eagles, being less cautious and experienced, are most prone to being severely "oiled". Alcids such as murres tend to become especially important in the diet of eagles in coastal Norway during winter, especially near offshore islands, when coastal fish tend to move to deeper waters. At least eight species of dabbling duck are known in
34310-435: The form of a physical destruction of niche habitats. The widespread destruction of tropical rainforests and replacement with open pastureland is widely cited as an example of this; elimination of the dense forest eliminated the infrastructure needed by many species to survive. For example, a fern that depends on dense shade for protection from direct sunlight can no longer survive without forest to shelter it. Another example
34545-629: The fossil record, the Woodward's eagle , which resided in North America, rivaled the Haast's in at least the aspect of total length. Female eagles were larger than males. Most estimates place the female Haast's eagles in the range of 10–18 kg (22–40 lb) and males around 9–12 kg (20–26 lb). A comparison with living eagles of the Australasian region resulted in estimated masses in Haast's eagles of 11.5 kg (25 lb) for males and 14 kg (31 lb) for females. One source estimates that
34780-544: The frigid weather. From Russia, breeding populations spill somewhat into northernmost Mongolia, extreme northwestern China and northern North Korea . The white-tailed eagle also breeds on Sakhalin Island , the Kuril Islands and Hokkaido, the northernmost island of Japan. The wintering range is less well understood for the white-tailed eagle given the extreme reductions and fluctuations of northern breeding populations over
35015-580: The habitat retreat of taxa approaching extinction. Possible causes of the higher extinction risk in species with more sexual selection shown by the comprehensive fossil studies that rule out such error sources include expensive sexually selected ornaments having negative effects on the ability to survive natural selection , as well as sexual selection removing a diversity of genes that under current ecological conditions are neutral for natural selection but some of which may be important for surviving climate change. There have been at least five mass extinctions in
35250-660: The heaviest losses include the Cape Floristic Region and the Caribbean Basin . These areas might see a doubling of present carbon dioxide levels and rising temperatures that could eliminate 56,000 plant and 3,700 animal species. Climate change has also been found to be a factor in habitat loss and desertification . Studies of fossils following species from the time they evolved to their extinction show that species with high sexual dimorphism , especially characteristics in males that are used to compete for mating, are at
35485-447: The history of life on earth, and four in the last 350 million years in which many species have disappeared in a relatively short period of geological time. A massive eruptive event that released large quantities of tephra particles into the atmosphere is considered to be one likely cause of the " Permian–Triassic extinction event " about 250 million years ago, which is estimated to have killed 90% of species then existing. There
35720-475: The human era since the Late Pleistocene would require 5 to 7 million years to recover. According to the 2019 Global Assessment Report on Biodiversity and Ecosystem Services by IPBES , the biomass of wild mammals has fallen by 82%, natural ecosystems have lost about half their area and a million species are at risk of extinction—all largely as a result of human actions. Twenty-five percent of plant and animal species are threatened with extinction. In
35955-412: The hunters who filled the same niche as top-niche mammalian predators . One study estimated the total population of Haast's eagle at 3,000 to 4,500 breeding pairs. Early Māori settlers arrived in New Zealand sometime between AD 1250 and AD 1275, The Māori preyed heavily on large flightless birds, including all moa species. The hunting pressure from both the Māori and the eagle eventually led
36190-700: The hunting success rates on healthy birds can be low as revealed in studying wintering eagles in Sweden attempting to hunt mallards ( Anas platyrhynchos ). White-tailed eagles also regularly pirate food from otters and other birds including cormorants , gulls , ospreys , corvids and various other raptors . Carrion is often the primary food source during lean winter months, with fish and ungulates preferred but everything from cetaceans to livestock to even humans being eaten after death. From studies of captive white-tailed eagles, daily food requirements were estimated at 500 to 600 g (1.1 to 1.3 lb), which
36425-431: The introduced ( or hybrid ) species. Endemic populations can face such extinctions when new populations are imported or selectively bred by people, or when habitat modification brings previously isolated species into contact. Extinction is likeliest for rare species coming into contact with more abundant ones; interbreeding can swamp the rarer gene pool and create hybrids, depleting the purebred gene pool (for example,
36660-603: The largest beaks of eagles today (from the Philippine and the Steller's sea eagle) reach a little more than 7 cm (3 in); and the longest tarsal measurements (from the Philippine and the Papuan eagle , Harpyopsis novaeguineae ) top out around 14 cm ( 5 + 1 ⁄ 2 in). The talons of the Haast's eagle were similar in length to those of the harpy eagle, with a front-left talon length of 4.9 to 6.15 cm ( 1 + 15 ⁄ 16 to 2 + 7 ⁄ 16 in) and
36895-432: The largest females could have weighed more than 16.5 kg (36 lb). The largest extant eagles, none of which are verified to exceed 9 kg (20 lb) in a wild state, are about forty percent smaller in body size than Haast's eagles. It had a relatively short wingspan for its size. It is estimated that the grown female typically spanned up to 2.6 m (8 ft 6 in), possibly up to 3 m (10 ft) in
37130-524: The largest living birds of prey. It is the largest of the dozen species of eagle found in Europe and the largest eagle across its distribution, excluding the Russian Far East and (during the winter) Hokkaido, Japan, where it co-exists with its larger cousin, Steller's sea eagle. The white-tailed eagle is sometimes considered the fourth largest eagle in the world and is, on average, the fourth heaviest eagle in
37365-457: The largest males perhaps the heaviest recorded modern male eagle, as male harpy and Philippine eagles (being more sexually dimorphic in favour of the female) are not known to exceed 5 kg (11 lb) (the highest weights for male Steller's sea eagle are not known). The global mean body mass of white-tailed eagles is estimated at approximately 5 kg (11 lb). The average female Steller's sea eagle may weigh just under 25% more than
37600-567: The largest seabirds they encounter, such as great cormorants ( Phalacrocorax carbo ), and in some cases, such as in the Baltic Sea, have nearly destroyed whole colonies, from the eggs to the adults which average about 2.57 kg (5.7 lb). In the Estonian island of Hiiumaa , home to at least 25 pairs of sea eagles, as many as 26 individuals have been observed simultaneously culling a single cormorant colony. Similarly large numbers were taken of
37835-421: The largest talon on all accipitrids, is 37 to 46 mm (1.5 to 1.8 in) in length, averaging 40.9 mm (1.61 in). The hallux claw averages about a centimeter less than that of a golden eagle and is more sharply curved, an adaptation to prevent escape of slippery prey such as fish, while that of a bald eagle is similarly about 40.4 mm (1.59 in) and of similar curvature. The exposed culmen
38070-454: The largest wingspan of any living eagle. The Steller's sea eagle, which is larger in weight, total length and non-wing standard measurements, may be the closest rival for median wingspan amongst living eagles. The white-tailed eagle does appear to outsize the average wingspan of the wedge-tailed eagle ( Aquila audax ), which is sometimes also titled the largest winged extant eagle due to an exceptionally large individual shot in 1931, although
38305-402: The last call ended with a lower ko-ko-ko , the perched call of females is similar but deeper, a krau-krau-krau-uik-ik . Typically, the perched version of their calls tend to be shriller and higher than those issued in flight. In courtship display, male calls krau-krau-krau-uik-ik-ik answered by females with a lower ra-rack-rack-rack-rack . Young in nest call a shrilly piieh-piieh , while
38540-485: The last few centuries, so that the delineation of regular wintering areas versus areas of mere vagrancy is difficult to ascertain. It is known that a small number winter on Etang de Lindre of Lorraine , France as well as an area on the border of France to Germany around Strasbourg , with vagrants to elsewhere in France, as well as to Spain , Portugal and Malta . A well-defined wintering population may occur in much of
38775-476: The latest, possibly (if the most ancient fossil record is correctly assigned to this genus) as early as the early or middle Oligocene , about 28 mya . A recent genetic study of mitochondrial DNA is consistent with this idea. Greenlandic white-tailed eagles (proposed as H. a. groenlandicus ) form, on evolutionary time scales, a relatively recently founded population that has not yet accumulated many unique genetic characteristics and may not strictly fulfill
39010-603: The leading prey species is the salmonid, the Arctic char ( Salvelinus alpinus ), which comprised 27.2% of 660 prey items. The secondary prey in Greenland was recorded as two species of cod . While the average weight of cod taken here was estimated at only 420 to 640 g (0.93 to 1.41 lb) and the average char at 660 to 740 g (1.46 to 1.63 lb), The eagles occasionally brought larger individuals up to 2.2 kg (4.9 lb) for cods and up to 3.2 kg (7.1 lb) for chars respectively. In Norway, of 524 fish prey items,
39245-417: The length (but perhaps not the girth) of the truly massive bill of the Steller's sea eagle. The adult white-tailed eagle is a greyish mid-brown colour overall. The plumage is fairly uniform over most of the body and wings, but the upper wing coverts are typically somewhat paler. In the adult, the head, neck and upper breast have a distinctly paler appearance than the rest of the plumage and most often have
39480-447: The little eagle than the booted eagle, with an estimated divergence from the little eagle around 2.2 million years ago. It was placed in the genus Aquila by recent taxonomists. Haast's eagle was one of the largest known true raptors . In length and weight, it was even larger than the largest living vulture (the Andean condor ). Another giant bird (not actually an eagle save for in name) more recently and scantily described from
39715-485: The main drivers of the modern extinction crisis. In January 2020, the UN's Convention on Biological Diversity drafted a plan to mitigate the contemporary extinction crisis by establishing a deadline of 2030 to protect 30% of the Earth's land and oceans and reduce pollution by 50%, with the goal of allowing for the restoration of ecosystems by 2050. The 2020 United Nations ' Global Biodiversity Outlook report stated that of
39950-443: The major islands. An ancient DNA study published in 2015 characterized the rapidly evolving mitochondrial control region of one of these specimens. DNA from a ~3,500-year-old sea eagle skeleton found in a lava cave on Maui was sequenced. Phylogenetic analyses suggested that the Hawaiian eagle represents a distinct (>3% divergent) mtDNA lineage that is most closely related to extant white-tailed eagles. Based on fossil calibration,
40185-489: The mallard's flightlessness during eclipse plumage may result in eagles hunting them intensely only in late summer. Due to this mallards are usually a secondary prey species year around. The largest known representation of mallards in the diet were from Müritz National Park in Germany, where mallards were the third best represented prey species at 10.1% of 247 items and from Augustów Primeval Forest in Poland, where mallards were
40420-413: The mantle, back and upper wing. The head of the juvenile is normally a blackish-brown hue, somewhat darker and always more uniform than most of the other feathers. The juvenile's tail tends to be a washed out greyish-cream colour with messy blackish colour on the feather edges and on the tips. Some individual juveniles may exhibit some faint barring on the tail while others may appear largely dirty whitish on
40655-421: The moa to extinction by around 1440 to 1445. Both eagles and Māori likely competed for the same foods. Unlike the adaptable humans, eagles were dependent on the native medium and large-sized flightless birds, being specialized in hunting them. The loss of its primary prey caused the Haast's eagle to become extinct at about the same time as its prey. Some believe that these birds are described in many legends of
40890-402: The mode of its ancestors' soaring flight in favour of navigating through a crowded woodland environment. Haast's eagles are likely to have hunted within the dense shrubland and forests of New Zealand, somewhat akin to other forest-dwelling raptors like the goshawks or harpy eagle . Some wing and leg remains of Haast's eagles permit direct comparison with living eagles. The harpy eagle,
41125-421: The modern understanding of extinction as the end of a species was incompatible with the prevailing worldview. Prior to the 19th century, much of Western society adhered to the belief that the world was created by God and as such was complete and perfect. This concept reached its heyday in the 1700s with the peak popularity of a theological concept called the great chain of being , in which all life on earth, from
41360-588: The most complete picture attainable. During winter, mammal prey can become more important in foods locally, as indicated in Scotland and shown in Norway and eastern Germany. As much as 41% of the diet can be made up of mammals, as was the case on the Kola Peninsula . There is evidence of strong seasonal shifts in food habits in several parts of the range, usually the largest portions of fish are caught during warmer months while birds and mammals are more important in
41595-411: The most diverse group in their prey spectrum. While hunting birds, this massive, relatively slow-flying eagle requires an element of surprise, with often a tactful use of cover or bright sunlight upon the approach from a nearby perch. For example, grey herons ( Ardea cinerea ) have been caught after an eagle used a low flight over turbulent water to ambush them. However, even with a stealthy attack,
41830-409: The much smaller little eagle ( Hieraaetus morphnoides ) as well as the booted eagle ( Hieraaetus pennatus ) and not, as previously thought, to the large wedge-tailed eagle ( Aquila audax ). Harpagornis moorei was therefore reclassified as Hieraaetus moorei . H. moorei is estimated to have diverged from these smaller eagles as recently as 1.8 million to 700,000 years ago. If this estimate
42065-490: The name of a species or other taxon normally indicates its status as extinct. Examples of species and subspecies that are extinct include: A species is extinct when the last existing member dies. Extinction therefore becomes a certainty when there are no surviving individuals that can reproduce and create a new generation. A species may become functionally extinct when only a handful of individuals survive, which cannot reproduce due to poor health, age, sparse distribution over
42300-534: The name relates to the eagle, given the massive size and strength of the bird. However, it has also been argued that the " hakawai " and " hōkioi " legends refer to the Austral snipe —in particular the extinct South Island species. Artwork depicting Haast's eagle now may be viewed at OceanaGold 's Heritage and Art Park at Macraes , Otago , New Zealand. The sculpture, weighing approximately 750 kg (1,650 lb), standing 7.5 metres (25 ft) tall, and depicted with
42535-469: The natural course of events, species become extinct for a number of reasons, including but not limited to: extinction of a necessary host, prey or pollinator, interspecific competition , inability to deal with evolving diseases and changing environmental conditions (particularly sudden changes) which can act to introduce novel predators, or to remove prey. Recently in geological time, humans have become an additional cause of extinction of some species, either as
42770-410: The newly emerging school of uniformitarianism . Jean-Baptiste Lamarck , a gradualist and colleague of Cuvier, saw the fossils of different life forms as evidence of the mutable character of species. While Lamarck did not deny the possibility of extinction, he believed that it was exceptional and rare and that most of the change in species over time was due to gradual change. Unlike Cuvier, Lamarck
43005-455: The northern part of the Caspian Sea and some central and southern parts of Kazakhstan, the white-tailed eagle may (or may not) live alongside the rarer, relatively poorly-known Pallas's fish eagle . The Pallas's juveniles are more distinctively whitish marked on the underwing. In flight or perched, the Pallas's fish eagle are usually markedly smaller and slighter than white-tailed eagles with
43240-399: The original population, thereby increasing the chance of extinction. Habitat degradation is currently the main anthropogenic cause of species extinctions. The main cause of habitat degradation worldwide is agriculture, with urban sprawl , logging, mining, and some fishing practices close behind. The degradation of a species' habitat may alter the fitness landscape to such an extent that
43475-763: The prey spectrum. Due to the social inclination of dabbling ducks, they perhaps have the most success hunting isolated birds but they've also been taken from panic-stricken flocks as well. Despite the difficulty of taking them, dabbling ducks of unidentified species were found to be the main food of white-tailed eagles in Lake Baikal , where they comprised 51.8% of 199 prey items. In Fennoscandia , they are attracted to coastal waters during winter to attack large numbers of diving ducks including eiders, common goldeneye ( Bucephala clangula ), goosander ( Mergus merganser ) and red-breasted merganser ( Mergus serrator ), tufted ducks ( Aythya fuligula ) and scoters . Year around in Åland , 66.2% of 5161 food items were birds, while in
43710-620: The primary position in the diet. From 26 accumulated food studies for this species, prey remains and pellets show that about 48.5% of the diet is made up of birds, 39.95% by fish, 9.95% by mammals and 1.6% by other foods. In total, more than 300 prey species are known throughout the bird's range. However, based on studies of prey remains and pellets in laboratories from Greenland white-tailed eagles, birds were shown to be biased in both kinds of remains (pellets and prey remains) whereas in situ study and direct nest observation favour fish. Going on pellet/remains alone here in Greenland from 557 items in
43945-702: The process of speciation —where new varieties of organisms arise and thrive when they are able to find and exploit an ecological niche —and species become extinct when they are no longer able to survive in changing conditions or against superior competition . The relationship between animals and their ecological niches has been firmly established. A typical species becomes extinct within 10 million years of its first appearance, although some species, called living fossils , survive with little to no morphological change for hundreds of millions of years. Mass extinctions are relatively rare events; however, isolated extinctions of species and clades are quite common, and are
44180-422: The rapidly increasing Danish population have found that when well-protected, they may regularly forage in habitats near significant humans populations, even in the outskirts of cities, and they can also successfully breed in such locations. White-tailed eagles spend much of their day perched on trees or crags, and may often not move for hours. Perhaps up to 90% of a day may be spent perched, especially if weather
44415-548: The reintroduced birds of Scotland of Norwegian stock) 4.98 kg (11.0 lb) in 39 males and 6.06 kg (13.4 lb) in 43 females. In comparison, the weight ranges for white-tailed eagles from Northeast China were claimed to be only 2.8 to 3.78 kg (6.2 to 8.3 lb) in males and 3.75 to 4.6 kg (8.3 to 10.1 lb) in females. The heaviest female white-tailed eagles can apparently weigh as much as 7.5 to 8 kg (17 to 18 lb) and even males can sometimes weigh up to 6.5 kg (14 lb), which would make
44650-410: The relative importance of genetic factors compared to environmental ones as the causes of extinction has been compared to the debate on nature and nurture . The question of whether more extinctions in the fossil record have been caused by evolution or by competition or by predation or by disease or by catastrophe is a subject of discussion; Mark Newman, the author of Modeling Extinction , argues for
44885-413: The sea eagles include Accipiters , harriers , chanting-goshawks and buteonines . Notably excluded from their relations are most other species referred to as "eagles", including booted eagles and snake and serpent eagles . The white-tailed eagle itself forms a species pair with the bald eagle . These diverged from other sea eagles at the beginning of the early Miocene (c. 10 mya ) at
45120-425: The second most numerous prey and made up 9.84% of 803 items. Taken more preferentially where they occur are common eiders. When hunting eiders, perhaps the largest of diving ducks at a mean weight of 2.06 kg (4.5 lb), white-tailed eagles frequently force the eider to dive repeatedly until it is exhausted and can be captured. When sitting on the nest, the female common eider will try to escape in flight but
45355-518: The second most often recorded prey species in both Müritz National Park (Germany), where they made up 16.42% of 247 prey items, and in Austria, where they made up 9.5% of 349 items. They will take many goslings during summer, as greylag goslings alone can comprise up 23% of the seasonal bird prey. Fully-grown greylag geese up to 4 kg (8.8 lb), especially infirm individuals are also taken in other seasons. White-tailed eagles are also known to attack and prey on other geese, ranging in size from
45590-584: The sexes are rarely this discrepant in standard measurements. Among standard measurements, the wing chord is 552 to 695 mm (21.7 to 27.4 in) in males, averaging 606 and 645 mm (23.9 and 25.4 in) in European adults and juveniles, respectively, and 646.5 mm (25.45 in) in Greenland males. In females, the wing chord may measure 605 to 740 mm (23.8 to 29.1 in), averaging 668 and 685 mm (26.3 and 27.0 in) in European adults and juveniles, respectively, and 691.3 mm (27.22 in) in Greenland females. Adult tail length
45825-407: The short summers ), northern and western Iceland , and the reintroduced populations in some areas of England (re-established in 2019 ), Ireland and Scotland, particularly conserved coastal spots. In mainland Europe the range is expanding, with Europe's largest population breeding in coastal Norway (broadly), northern and southwestern Finland , eastern Sweden , broadly in Denmark , islands of
46060-417: The size of the bird". The male call is oft transcribed as gri-gri-gri or krick-krick-krick , while the female is a deeper gra-gra-gra-gra or krau-krau-krau-krau . These will increase in tempo and pitch, with about 15–30 calls in a sequence. Often pairs will duet during early spring, in flight or from a perch. When perched, the male calls kyi-kyi-kyi-kli-kliek-yak with the head thrown back and upwards in
46295-492: The slighter, more angular skull possessed by males. In disposition, the male juveniles are said to be more highly strung and higher voiced than their female counterparts. The head gradually grows paler over several years. The whitish mottling may increase on the upperparts, belly and especially on the underwing area later into their third year (considered the first subadult plumage) and subadult birds can appear fairly blotched with white but much individual variation in colouring
46530-535: The southwesterly direction to the shores of the Baltic Sea. One from Finland was recovered 520 km (320 mi) west in northern Norway and another was found as far south as Bulgaria. In more southerly areas, winter movements are drawn-out and irregular, with most mature pairs probably never leaving their nesting haunts year-around. Those that breed on inland waterways may migrate to sea coast. German juveniles usually do not travel far, with most recorded to travel less than 50 km (31 mi) from their nests and
46765-448: The species appear to take different migratory routes in autumn and spring, traveling from north-central Kamchatka thru the Kurile islands to Hokkaido in autumn, while in spring these eagles travel north through Sakhalin and the Okhotsk Coast . In the White Sea area, southward moments begin in September with most white-tailed eagles being gone by November but in mild winters some adults may remain behind. Some white-tailed eagles from
47000-460: The species is no longer able to survive and becomes extinct. This may occur by direct effects, such as the environment becoming toxic , or indirectly, by limiting a species' ability to compete effectively for diminished resources or against new competitor species. Habitat destruction, particularly the removal of vegetation that stabilizes soil, enhances erosion and diminishes nutrient availability in terrestrial ecosystems. This degradation can lead to
47235-423: The species live largely as scavengers, usually by coming across available carrion or watching for the activity of corvids , vultures or other raptors. White-tailed eagles in northeastern Germany were shown to hunt mostly from perches, in a "sit-and-wait" style, usually from a prominent tree perch. Like other sea eagles, they can only capture fish normally in the littoral zone , seldom hunting fish when they exceed
47470-481: The species' extinction. Moa would be up to fifteen times the weight of the eagle. Its large beak also could be used to rip into the internal organs of its prey and death then would have been caused by blood loss. Due to the absence of other large predators or kleptoparasites , a Haast's eagle could easily have monopolised a single large kill over a number of days. Its prey, the moa, could weigh up to 200 kg (440 lb). A 2021 analysis showed that, while predatory,
47705-430: The sudden introduction of human beings to environments full of animals that had never seen them before and were therefore completely unadapted to their predation techniques. Coextinction refers to the loss of a species due to the extinction of another; for example, the extinction of parasitic insects following the loss of their hosts. Coextinction can also occur when a species loses its pollinator , or to predators in
47940-512: The sun's eye.' The white-tailed eagle is a member of the genus Haliaeetus , a monophylic group comprising 11 living species, including the closely related Ichthyophaga fish eagles which may or may not be part of a separate genus. The latter group, comprising the lesser ( Haliaeetus humilis ) and the grey-headed fish eagle ( Haliaeetus ichthyaetus ), differ mostly in life history, being more fully devoted to fish eating and habituating wooded areas, especially in mountainous areas. In appearance
48175-404: The tail colour is similar at the various stages of development but the shape is more distinctive, especially the bolder wedge shape of the Steller's. The cinereous vulture ( Aegypius monachus ) may too be considered superficially similar to the juvenile white-tailed eagle, but it is considerably larger and longer-winged and possesses a more uniform and darker hue with conspicuous paler legs and
48410-399: The tail. The bill of juveniles is usually almost half dark brown from the tip and half dirty, dull yellowish or grey to the base, while the feet are usually a dirty yellow and the eyes are a darkish brown. Juvenile males may average a slightly darker brown plumage with less speckling on the upper body than like-age females; their head and neck plumes may also appear shorter, which can accentuate
48645-479: The three sites in different parts of Finland birds made up 51.1% of 3152 food items. In Germany, 52.4% of 1637 prey items were birds, mostly coots and unidentified waterfowl. More locally in Germany, in Müritz National Park the percentage of birds in the diet climbs to 65.73% Birds were strongly dominant in food records from Scotland, making up 73.53% of 1930 prey items, and in Kandalaksha Nature Reserve , where they comprised 75% of 523 prey items. While most of
48880-412: The tiniest microorganism to God, is linked in a continuous chain. The extinction of a species was impossible under this model, as it would create gaps or missing links in the chain and destroy the natural order. Thomas Jefferson was a firm supporter of the great chain of being and an opponent of extinction, famously denying the extinction of the woolly mammoth on the grounds that nature never allows
49115-447: The tip in flight and the white-tailed eagle is well known to soar extensively. This species can be surprisingly maneuverable on the wing, usually during aerial displays or dogfights with other birds. These eagles may also maneuver by half-closing both wings or fully closing one wing. The white-tailed eagle is considered a vocal bird of prey during the breeding season, although some authors consider their voice "not loud or impressive for
49350-448: The total extinction of the dodo and the extirpation of indigenous horses to the British Isles. He similarly argued against mass extinctions , believing that any extinction must be a gradual process. Lyell also showed that Cuvier's original interpretation of the Parisian strata was incorrect. Instead of the catastrophic floods inferred by Cuvier, Lyell demonstrated that patterns of saltwater and freshwater deposits , like those seen in
49585-468: The two Ichthyaetus are slenderer, longer tailed and more uniform and grey in colour than typical sea eagles. This species pair may not be genetically distinct enough to warrant division into separate genera. Other than these Ichthyophaga -type species found farther north in Asia, Sanford's sea eagle ( Haliaeetus sanfordi ) of the Solomon Islands is the most atypical Haliaeetus , retaining rufous-brown plumage into adulthood (this particularly resembling
49820-535: The two species. The white-tailed eagle does have a significantly larger wing chord and average wingspan than the bald eagle, but the latter usually possesses a longer tail, resulting in a larger total length than the white-tailed eagle and a larger mean tarsal length. Size variation is generally a clinal trend and is normally quantified using standard measurements such as wing, tail and tarsal length, or body mass, rather than wingspan or total length. As expected for many widely distributed animals of varied lineages,
50055-469: The water to the nearest bank or shore. While this would leave them waterlogged, of course, the food yield from such a catch is obviously attractive. White-tailed eagles have been photographed doing this with a large fish successfully in Greenland and 35 such cases were reported in Norway alone. The most frequently recorded prey species in 18 food studies from across the range is the northern pike ( Esox lucius ), present in at least 16 of those studies. Pike
50290-525: The water's surface. Therefore, lurking benthic fish such as lumpsuckers are more vulnerable than many. Besides vulnerability, habitat, and prey behavior, fish body size may be a driver in the piscivore's dietary preferences. White-tailed eagles usually can take various fish from 0.1 to 8 kg (0.22 to 17.64 lb), but fish ranging 0.5 to 3 kg (1.1 to 6.6 lb) typically preferred. Similarly, studies have indicated that fish less than 20 cm (7.9 in) are taken infrequently, since they have
50525-517: The western part of its range, with eagles even breeding as far north as Greenland, Iceland and coastal Norway not moving at all for winter, but for some southward juvenile movements following dispersal. Juveniles overall are more migratory and dispersive and leave natal areas sooner, which is by August–September in northwestern Europe and return later, by March/April, than adults do. Few Norwegian juveniles, per banding studies, were recorded to travel any considerable distance. Extreme cases include one that
50760-622: The white-tailed eagle and tends to be more dashing in flight, which is usually done with a distinct dihedral. When perched, the golden eagle looks more sleek and compact than the rangier white-tailed eagle and tends to be a darker, richer hue of brown. Golden eagles have a much shorter neck, with a smaller head and bill and a longer, squarer tail. White wing patches of juveniles are also differently distributed in golden than juvenile white-tailed eagles. This eagle breeds in northern Europe and northern Asia. Their range extends to as far west as southern Greenland (prevented from breeding further north due to
50995-453: The white-tailed eagle conforms to Bergmann's rule in that more northerly birds tend to outsize those found relatively closer to the Equator . Average size also decreases from west to east across its distribution. The largest white-tailed eagles appear to be found in Greenland , these being slightly larger than those from Ireland , Scotland and Scandinavia and notably larger than eagles from central Europe , especially in proportions of
51230-400: The white-tailed eagle's prey spectrum are the family Cyprinidae , of which more than 20 species are known to be predated including the common bream. Others taken with some preference may include salmonids and cod and their allies , both families known to obtain relatively large body sizes and occasional habituate shallow water, as well as lumpsuckers because they are benthic. In Greenland,
51465-559: The white-tailed eagle's range. White-tailed eagles can hunt fish in fresh or saltwater as well as those that prefer brackish water areas. However, they are restricted to taking fish in extremely shallow water, often by preference in water less than 1 m (3.3 ft) deep. Ideal fishing areas can be found in areas such as the Baltic Sea, where low coasts and archipelagos often have relatively shallow water. While healthy, large fish are often taken as well, white-tailed eagles often take out sickly, injured, or already dead fish. In some cases,
51700-530: The wider scientific community of his theory. Cuvier was a well-regarded geologist, lauded for his ability to reconstruct the anatomy of an unknown species from a few fragments of bone. His primary evidence for extinction came from mammoth skulls found in the Paris basin . Cuvier recognized them as distinct from any known living species of elephant, and argued that it was highly unlikely such an enormous animal would go undiscovered. In 1812, Cuvier, along with Alexandre Brongniart and Geoffroy Saint-Hilaire , mapped
51935-537: The wing area. Those from the southerly portions of the breeding range, such as Asia Minor (principally Turkey ), southern Kazakhstan , and Korea Bay , appear to be the smallest-bodied population but there have been limited measurements and published weights known for these extremely sporadic and rare Asian populations of eagle. Furthermore, weights of fully grown eagles from Greenland are not known. Unlike many accipitrids, juvenile white-tailed eagles (and seemingly other sea eagles as well) are often of similar weight to
52170-591: The wing at a height of at least 200 m (660 ft). In Norway, plunge-diving is considered rare. At times they will also fish by wading into shallows, often from shores or gravel islands. The species will at times variously follow fishing boats , readily exploits commercial fisheries , stocked lakes , carp ponds and the like, and scavenges dead fish or fish-offal in a wide range of situations. When it comes to non-fish prey, it has been said that white-tailed eagles often hunt by flying low over sea coast or lakeshore and attempt to surprise victims. However,
52405-574: The wing shape of a white-tailed eagle but are far smaller and shorter winged and never bear a protruding head. Similarly, the eastern imperial eagle ( Aquila heliaca ) may suggest a white-tailed eagle in its flat wing profile and relatively large head and neck but is also visibly smaller with far less broad wings and a relatively longer tail. Like all Clanga and Aquila , both greater spotted and eastern imperial eagles should be obviously distinct from white-tailed eagles by plumage characteristics. The golden eagle usually appears slightly smaller than
52640-444: The winter. Other established wintering areas are known in Europe in west-central Italy , northern Austria, fairly broadly in southern Slovakia and northern Hungary and a few protected pockets of Southeast Europe apart from the portions in the north and east where they still breed. Intermittent forms of vagrancy and migration (most from eagles that breed in or disperse from Russia) are known to occur in several areas of Turkey,
52875-441: The world. The only extant eagle species known to be more massive in mean bulk are the Steller's sea eagle ( Haliaeetus pelagicus ), the harpy eagle ( Harpia harpyja ) and the Philippine eagle ( Pithecophaga jefferyi ). The white-tailed eagle measures anywhere from 66 to 94 cm (26 to 37 in) in total length with a typical wingspan of 1.78 to 2.45 m (5 ft 10 in to 8 ft 0 in). This species may have
53110-400: The year near large bodies of open water, including coastal saltwater areas and inland freshwater lakes , wetlands, bogs and rivers . It requires old-growth trees or ample sea cliffs for nesting, and an abundant food supply of fish and birds (largely water birds ) amongst nearly any other available prey. Both a powerful apex predator and an opportunistic scavenger , it forms
53345-537: The young and adults of 5.1 kg (11 lb) common cranes ( Grus grus ). The largest waterbirds species preyed upon are swans, including mute ( Cygnus olor ), whooper ( Cygnus cygnus ) and Bewick's swans ( Cygnus columbianus bewickii ). While cygnets and disabled birds (either by natural conditions such as ice or by human hunters) are at the greatest risk for eagle predation, white-tailed eagles have preyed upon even healthy adult swans up to 10 kg (22 lb). They are reported to have attacked and eaten
53580-536: Was comprised by fish, led by the common carp ( Cyprinus carpio ) and Prussian carp ( Carassius gibelio ). Similarly, in Podlaskie Voivodeship , Poland 55% of all the identified fish species brought to the nest were common carps, up to 2.1 kg (4.6 lb) in weight with the mean mass of 493 g (1.087 lb). However, there are reports that white-tailed eagles managed to catch extreme sizes of carps, up to 15 kg (33 lb)in weight. White-tailed eagles are known to prey on about 170 species of bird,
53815-425: Was difficult to disprove. When parts of the world had not been thoroughly examined and charted, scientists could not rule out that animals found only in the fossil record were not simply "hiding" in unexplored regions of the Earth. Georges Cuvier is credited with establishing the modern conception of extinction in a 1796 lecture to the French Institute , though he would spend most of his career trying to convince
54050-469: Was found 720 km (450 mi) south of its nest near Karlstad , Sweden, another set of four colour-marked first-year juveniles were also recorded to turn up in southern Sweden but one was found down to the Wadden Sea in the Netherlands and it is likely that trickling down numbers of Norwegian post-dispersal juveniles have gone onto form much of the known Dutch white-tailed eagle population. In contrast, young from Finland and Sweden tend to distribute to
54285-419: Was found to affect breeding white-tailed eagles less so than it seemed to affect breeding black storks ( Ciconia nigra ). On the other hand, from studying wintering white-tailed eagles in partially or heavily disturbed wetlands in parts of the Netherlands shows that such areas cannot support the eagles for any long-term period and may only be visited for a day or two by individual eagles. Conversely, reviews of
54520-662: Was found to be the main prey species in both the Baltic Sea and Lapland in Sweden, at three breeding locations in Finland, in two studies from Germany, and in Belarus . The maximum representation of pike known was in Lapland, where they comprised 38.2% of 809 food items. While an average mature weight for a pike is around 1.4 kg (3.1 lb), white-tailed eagles often attack larger-sized pike, with an estimated average weight range of 2 to 5 kg (4.4 to 11.0 lb). The largest pike taken by white-tailed eagles were even estimated to weigh around 12 to 15 kg (26 to 33 lb). The next most widely reported fish prey species
54755-399: Was found with the disembodied feet of a white-tailed eagle still embedded in its back, presumed the eagle drowned after being overpowered and drug under only to rot off, leaving only feet. Since they do not have the waterproofing oils on the plumage of the more accomplished raptorial diver, the osprey ( Pandion haliaetus ), white-tailed eagles prefer not to get their feathers wet as it can take
54990-430: Was not until 1982, when David Raup and Jack Sepkoski published their seminal paper on mass extinctions, that Cuvier was vindicated and catastrophic extinction was accepted as an important mechanism . The current understanding of extinction is a synthesis of the cataclysmic extinction events proposed by Cuvier, and the background extinction events proposed by Lyell and Darwin. Extinction is an important research topic in
55225-571: Was skeptical that catastrophic events of a scale large enough to cause total extinction were possible. In his geological history of the earth titled Hydrogeologie, Lamarck instead argued that the surface of the earth was shaped by gradual erosion and deposition by water, and that species changed over time in response to the changing environment. Charles Lyell , a noted geologist and founder of uniformitarianism , believed that past processes should be understood using present day processes. Like Lamarck, Lyell acknowledged that extinction could occur, noting
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