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79-396: Stictocarbo varius The Australian pied cormorant ( Phalacrocorax varius ), also known as the pied cormorant , pied shag , or great pied cormorant , is a medium-sized member of the cormorant family. It is found around the coasts of Australasia . In New Zealand, it is usually known either as the pied shag or by its Māori name of kāruhiruhi . Older sources may refer to it as

158-431: A monophyletic group, even after the removal of the distantly-related tropicbirds . Their relationships and delimitation – apart from being part of a "higher waterfowl" clade which is similar but not identical to Sibley and Ahlquist's "pan-Ciconiiformes" – remain mostly unresolved. Notwithstanding, all evidence agrees that the cormorants and shags are closer to the darters and Sulidae (gannets and boobies), and perhaps

237-495: A decrease in benthic macroinvertebrate biomass, which lead to the disappearance of food sources into the substrate. Because the benthic system regulates energy in aquatic ecosystems, studies have been made of the mechanisms of the benthic zone in order to better understand the ecosystem. Benthic diatoms have been used by the European Union's Water Framework Directive (WFD) to establish ecological quality ratios that determined

316-453: A few inches below the surface. The continental shelf is a gently sloping benthic region that extends away from the land mass. At the continental shelf edge, usually about 200 metres (660 ft) deep, the gradient greatly increases and is known as the continental slope. The continental slope drops down to the deep sea floor. The deep-sea floor is called the abyssal plain and is usually about 4,000 metres (13,000 ft) deep. The ocean floor

395-498: A large hooked bill, green eyes with a blue eye ring and black legs and feet. The eyes have a special nictitating membrane for underwater protection. The pied cormorant can often be seen spreading its wings after diving to help dry the feathers, as it has inadequate waterproofing. This lack of feather waterproofing may help the cormorant spend longer underwater due to decreased buoyancy effects. The two subspecies have slight differences in physical characteristics. Similar species include

474-843: A patch of bare yellow skin at the base of the bill. Breeds in European Arctic, winters in Europe and North Africa. Maritime. Mid-sized (70–80 cm), glossy black, in breeding plumage with a forehead crest curled to the front. Throughout the Americas. Mostly freshwater. Smallish to large (65–100 cm), nondescript brownish-black. One species with white tufts on sides of head in breeding plumage. Generally Subantarctic, but extending farther north in South America; many oceanic-island endemics. Maritime. Smallish to largish (65–80 cm), typically black above, white below, and with bare yellow or red skin in

553-403: A recovery period of 10–15 seconds between dives although this is dependent on depth. The birds feed in deep and shallow waters (although shallow habitats are more productive) with flock densities in proportion to the prey abundance. Hunting is typically performed as individuals (potentially to avoid kleptoparasitism ), although larger groups can be observed when schools of small fish are close to

632-639: A specimen in the Leverian Museum and on a watercolour by Georg Forster that belonged to Joseph Banks . Forster had accompanied James Cook on his second voyage to the Pacific Ocean . The Australian pied cormorant is now one of 12 species placed in the genus Phalacrocorax that was introduced in 1760 by the French zoologist Mathurin Jacques Brisson . Two subspecies are recognised: The pied cormorant

711-802: A symbiotic relationship with each other. In the deep sea, which covers 90–95% of the ocean floor, 90% of the total biomass is made up of prokaryotes. To release all the nutrients locked inside these microbes to the environment, viruses are important in making it available to other organisms. Modern seafloor mapping technologies have revealed linkages between seafloor geomorphology and benthic habitats, in which suites of benthic communities are associated with specific geomorphic settings. Examples include cold-water coral communities associated with seamounts and submarine canyons, kelp forests associated with inner shelf rocky reefs and rockfish associated with rocky escarpments on continental slopes. In oceanic environments, benthic habitats can also be zoned by depth. From

790-466: Is a nomen dubium and given its recent age probably not a separate genus. The remaining fossil species are not usually placed in a modern phylogenetic framework. While the numerous western US species are most likely prehistoric representatives of the coastal Urile or inland Nannopterum , the European fossils pose much more of a problem due to the singular common shag being intermediate in size between

869-473: Is a family of approximately 40 species of aquatic birds commonly known as cormorants and shags . Several different classifications of the family have been proposed, but in 2021 the International Ornithologists' Union (IOU) adopted a consensus taxonomy of seven genera . The great cormorant ( Phalacrocorax carbo ) and the common shag ( Gulosus aristotelis ) are the only two species of

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948-517: Is liable to result in some degree of convergent evolution and the bone is missing indisputable neornithine features, it is not entirely certain that the bone is correctly referred to this group. Phylogenetic evidence indicates that the cormorants diverged from their closest relatives, the darters, during the Late Oligocene, indicating that most of the claims of Cretaceous or early Paleogene cormorant occurrences are likely misidentifications. During

1027-455: Is long, thin and hooked. Their feet have webbing between all four toes. All species are fish-eaters, catching the prey by diving from the surface. They are excellent divers, and under water they propel themselves with their feet with help from their wings; some cormorant species have been found to dive as deep as 45 metres (150 ft). They have relatively short wings due to their need for economical movement underwater, and consequently have among

1106-409: Is not all flat but has submarine ridges and deep ocean trenches known as the hadal zone . For comparison, the pelagic zone is the descriptive term for the ecological region above the benthos, including the water column up to the surface. At the other end of the spectrum, benthos of the deep ocean includes the bottom levels of the oceanic abyssal zone . For information on animals that live in

1185-466: Is not easy to map or observe these organisms and their habitats, and most modern observations are made using remotely operated underwater vehicles (ROVs), and rarely submarines . Benthic macroinvertebrates have many important ecological functions, such as regulating the flow of materials and energy in river ecosystems through their food web linkages. Because of this correlation between flow of energy and nutrients, benthic macroinvertebrates have

1264-508: Is not even clear how many species are involved. Provisionally, the fossil species are thus all placed in Phalacrocorax here: The former "Phalacrocorax" (or "Oligocorax" ) mediterraneus is now considered to belong to the bathornithid Paracrax antiqua . "P." subvolans was actually a darter ( Anhinga ). Humans have used cormorants' fishing skills in various places in the world. Archaeological evidence suggests that cormorant fishing

1343-671: Is not sufficient to properly resolve several groups to satisfaction; in addition, many species remain unsampled, the fossil record has not been integrated in the data, and the effects of hybridisation – known in some Pacific species especially – on the DNA sequence data are unstudied. A multigene molecular phylogenetic study published in 2014 provided a genus-level phylogeny of the family. Microcarbo – 5 species Poikilocarbo – red-legged cormorant Urile – 4 species Phalacrocorax – 12 species Gulosus – European shag Nannopterum – 3 species Leucocarbo – 16 species As per

1422-495: Is predominantly black on its back and upper surface of the wings and white on the underside with males weighing approximately 2.2 kg and females 1.7 kg. It stands between 65–85 cm tall, with a wingspan of 110–130 cm. A small yellow patch between the bill and the eye on each side of the head is likely to have been the reason for the historical common name. It has large webbed feet which it utilises to pursue fish underwater, steering with half opened wings. The bird has

1501-655: Is recommended in the European Union benthic monitoring program (by Kelly 1998 for the United Kingdom then in the EU and for the EU as a whole by CEN 2003 and CEN 2004) and in some United States programs (by Moulton et al. 2002). Benthic gross primary production (GPP) may be important in maintaining biodiversity hotspots in littoral zones in large lake ecosystems . However, the relative contributions of benthic habitats within specific ecosystems are poorly explored and more research

1580-434: Is still practised as a cultural tradition. Benthic The benthic region of the ocean begins at the shore line ( intertidal or littoral zone ) and extends downward along the surface of the continental shelf out to sea. Thus, the region incorporates a great variety of physical conditions differing in: depth, light penetration and pressure. Depending on the water-body, the benthic zone may include areas that are only

1659-635: Is the Cornish name of the sea giant in the tale of Jack the Giant Killer . Indeed, "sea raven" or analogous terms were the usual terms for cormorants in Germanic languages until after the Middle Ages . The French explorer André Thévet commented in 1558: "the beak [is] similar to that of a cormorant or other corvid", which demonstrates that the erroneous belief that the birds were related to ravens lasted at least to

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1738-543: The Clements Checklist , formerly recognised only Microcarbo as a separate genus from Phalacrocorax . For details, see the article " List of cormorant species ". The details of the evolution of the cormorants are mostly unknown. Even the technique of using the distribution and relationships of a species to figure out where it came from, biogeography, usually very informative, does not give very specific data for this probably rather ancient and widespread group. However,

1817-781: The IOU , the IUCN Red List and BirdLife International , the family contains 7 genera: Around Indian Ocean, one species extending from Central Asia into Europe. Mostly in freshwater habitat. Small (about 50–60 cm long), nondescript black to dark brown (except for one species with white underparts). Subtropical to subantarctic Pacific South America, ranging a bit into the southwestern Atlantic. Maritime. Mid-sized (around 75 cm), grey with scalloped wings and contrasting white/yellow/red neck mark and bare parts. Its high-pitched chirping calls are quite unlike those of other cormorants. Northern Pacific, one species extending into subtropical waters on

1896-560: The Quercy Phosphorites of Quercy (France), dating to some time between the Late Eocene and the mid- Oligocene . All these early European species might belong to the basal group of "microcormorants", as they conform with them in size and seem to have inhabited the same habitat: subtropical coastal or inland waters. While this need not be more than convergence , the phylogeny of the modern (sub)genus Microcarbo – namely, whether

1975-573: The black-faced cormorant (slightly smaller) and the little pied cormorant (substantially smaller). The pied cormorant is listed of least concern in the IUCN red list of threatened species, reflecting its large range with a relatively stable population. In New Zealand its range on the east coast extends as far south as Christchurch , though this is a recent extension—older books report it no further south than Kaikōura . The range extensions have accompanied population recovery from heavy persecution in

2054-1017: The moojar (WA Christmas tree) before being carried by easterly winds or flowing waters to the sea where the spirit joins with the medi for its journey to Kurranup . Cormorant Microcarbo Poikilocarbo Urile Phalacrocorax Gulosus Nannopterum Leucocarbo Australocorax Lambrecht , 1931 Compsohalieus B. Brewer & Ridgway , 1884 Cormoranus Baillon , 1834 Dilophalieus Coues , 1903 Ecmeles Gistel, 1848 Euleucocarbo Voisin, 1973 Halietor Heine, 1860 Hydrocorax Vieillot , 1819 ( non Brisson, 1760: preoccupied ) Hypoleucus Reichenbach , 1852 Miocorax Lambrecht, 1933 Nesocarbo Voisin, 1973 Notocarbo Siegel-Causey, 1988 Pallasicarbo Coues, 1903 Paracorax Lambrecht, 1933 Pliocarbo Tugarinov , 1940 Stictocarbo Bonaparte, 1855 Viguacarbo Coues, 1903 Anatocarbo Nanocorax (see text) Phalacrocoracidae

2133-610: The "yellow-faced cormorant". The Australian pied cormorant was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus 's Systema Naturae . He placed it in the genus Pelecanus and coined the binomial name Pelecanus varius . Gmelin based his description on the "pied shag" from Queen Charlotte Sound , New Zealand, that had been described in 1785 by English ornithologist John Latham in his book A General Synopsis of Birds . Latham had based his own description on

2212-573: The 16th century. No consistent distinction exists between cormorants and shags. The names "cormorant" and "shag" were originally the common names of the two species of the family found in Great Britain  – Phalacrocorax carbo (now referred to by ornithologists as the great cormorant ) and Gulosus aristotelis (the European shag ). "Shag" refers to the bird's crest, which the British forms of

2291-603: The American West Coast. Maritime. Smallish to large (65–100 cm), generally black with metallic sheen (usually blue/green), in breeding plumage with bright bare facial skin in the eye region and two crests (crown and nape). Mostly around Indian Ocean, one species group extending throughout Eurasia and to Atlantic North America. Maritime to freshwater. Size very variable (60–100 cm), blackish with metallic sheen (usually bronze to purple) and/or white cheek and thigh patches or underside at least in breeding plumage; usually

2370-551: The Early Oligocene, perhaps some 30 million years ago, and that the Cretaceous fossils represent ancestral sulids, "pelecaniforms" or "higher waterbirds"; at least the last lineage is generally believed to have been already distinct and undergoing evolutionary radiation at the end of the Cretaceous . What can be said with near certainty is that AMNH FR 25272 is from a diving bird that used its feet for underwater locomotion; as this

2449-618: The North American ones placed in the expanded Phalacrocorax ; the latter might just as well be included in Nannopterum . A Late Oligocene fossil cormorant foot from Enspel , Germany, sometimes placed in Oligocorax , would then be referable to Nectornis if it proves not to be too distinct. Limicorallus , meanwhile, was initially believed to be a rail or a dabbling duck by some. There are also undescribed remains of apparent cormorants from

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2528-572: The Phalacrocoracidae; this was from a rather smaller bird, about the size of a long-tailed cormorant . However, cormorants likely originated much later, and these are likely misidentifications. As the Early Oligocene "Sula" ronzoni cannot be assigned to any of the sulid families—cormorants and shags, darters, and gannets and boobies—with certainty, the best interpretation is that the Phalacrocoracidae diverged from their closest ancestors in

2607-615: The Western Eurasian M. pygmaeus is a basal or highly derived member of its clade – is still not well understood at all as of 2022. Some other Paleogene remains are sometimes assigned to the Phalacrocoracidae, but these birds seem rather intermediate between cormorants and darters (and lack clear autapomorphies of either). Thus, they may be quite basal members of the Palacrocoracoidea . The taxa in question are: The supposed Late Pliocene/Early Pleistocene " Valenticarbo "

2686-517: The ability to influence food resources on fish and other organisms in aquatic ecosystems . For example, the addition of a moderate amount of nutrients to a river over the course of several years resulted in increases in invertebrate richness, abundance, and biomass . These in turn resulted in increased food resources for native species of fish with insignificant alteration of the macroinvertebrate community structure and trophic pathways. The presence of macroinvertebrates such as Amphipoda also affect

2765-464: The available evidence suggests that there has also been a great deal of convergent evolution ; for example the cliff shags are a convergent paraphyletic group. The proposed division into Phalacrocorax sensu stricto (or subfamily "Phalacrocoracinae") cormorants and Leucocarbo sensu lato (or "Leucocarboninae") shags does have some degree of merit. The resolution provided by the mtDNA 12S rRNA and ATPase subunits six and eight sequence data

2844-407: The benthos, and the degree of benthic-pelagic coupling. The benthos in a shallow region will have more available food than the benthos in the deep sea. Because of their reliance on it, microbes may become spatially dependent on detritus in the benthic zone. The microbes found in the benthic zone, specifically dinoflagellates and foraminifera , colonize quite rapidly on detritus matter while forming

2923-463: The birds to fish. In a common technique, a snare is tied near the base of the bird's throat, which allows the bird only to swallow small fish. When the bird captures and tries to swallow a large fish, the fish is caught in the bird's throat. When the bird returns to the fisherman's raft, the fisherman helps the bird to remove the fish from its throat. The method is not as common today, since more efficient methods of catching fish have been developed, but

3002-616: The body. In the past, the pied cormorant was seen as competition for commercial fishing and sometimes shot. Although typically found in marine habitat—sometimes solitary, sometimes in pairs, sometimes in vast flocks of hundreds or thousands—it is also attracted to inland waters, including lakes, deep and open wetlands, and rivers. In Australia, the birds can often be found at inland waterways while in New Zealand it prefers coastal areas close to its prey. Adult birds are sedentary and can often be seen roosting in trees, on rocks or logs in

3081-464: The breeding season. The bill is long, thin, and sharply hooked. Their feet have webbing between all four toes, as in their relatives. Habitat varies from species to species: some are restricted to seacoasts, while others occur in both coastal and inland waters to varying degrees. They range around the world, except for the central Pacific islands. All cormorants and shags are fish-eaters, dining on small eels , fish, and even water snakes. They dive from

3160-465: The broad mass of water, down as far as the depth to which no light penetrates. Benthos are the organisms that live in the benthic zone, and are different from those elsewhere in the water column ; even within the benthic zone variations in such factors as light penetration, temperature and salinity give rise to distinct differences, delineated vertically, in the groups of organisms supported. Many organisms adapted to deep-water pressure cannot survive in

3239-490: The city of Inuyama , Aichi . In Guilin , Guangxi , cormorants are famous for fishing on the shallow Li River . In Gifu, the Japanese cormorant ( P. capillatus ) is used; Chinese fishermen often employ great cormorants ( P. carbo ). In Europe, a similar practice was also used on Doiran Lake in the region of Macedonia . James VI and I appointed a keeper of cormorants, John Wood , and built ponds at Westminster to train

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3318-542: The closest living relatives of the cormorants and shags are the other families of the suborder Sulae — darters and gannets and boobies —which have a primarily Gondwanan distribution. Hence, at least the modern diversity of Sulae probably originated in the southern hemisphere. While the Leucocarbonines are almost certainly of southern Pacific origin—possibly even the Antarctic which, at the time when cormorants evolved,

3397-641: The creamy white patch on the cheeks of adult great cormorants , or the ornamental white head plumes prominent in Mediterranean birds of this species, but is certainly not a unifying characteristic of cormorants. The cormorant family was traditionally placed within the Pelecaniformes or, in the Sibley–Ahlquist taxonomy of the 1990s, the expanded Ciconiiformes . Pelecaniformes in the traditional sense—all waterbird groups with totipalmate foot webbing—are not

3476-437: The deeper areas of the oceans see aphotic zone . Generally, these include life forms that tolerate cool temperatures and low oxygen levels, but this depends on the depth of the water. As with oceans, the benthic zone is the floor of the lake, composed of accumulated sunken organic matter . The littoral zone is the zone bordering the shore; light penetrates easily and aquatic plants thrive. The pelagic zone represents

3555-457: The dominance of certain types of algae in Benthic ecosystems as well. In addition, because benthic zones are influenced by the flow of dead organic material , there have been studies conducted on the relationship between stream and river water flows and the resulting effects on the benthic zone. Low flow events show a restriction in nutrient transport from benthic substrates to food webs, and caused

3634-413: The early 1900s and likely represents recolonization of the former range. The pied cormorant is listed as Nationally Vulnerable in New Zealand. The population has been growing from around 700 breeding pairs in the 1950s to an estimated 3,000 pairs post 2000 (Refer to population trend data). In Australia it is only moderately common in the eastern states (both the coast and inland wetlands), but abundant in

3713-649: The ecological status of lakes in the UK. Beginning research is being made on benthic assemblages to see if they can be used as indicators of healthy aquatic ecosystems. Benthic assemblages in urbanized coastal regions are not functionally equivalent to benthic assemblages in untouched regions. Ecologists are attempting to understand the relationship between heterogeneity and maintaining biodiversity in aquatic ecosystems. Benthic algae has been used as an inherently good subject for studying short term changes and community responses to heterogeneous conditions in streams. Understanding

3792-464: The energy source for the benthic ecosystem is often marine snow . Marine snow is organic matter from higher up in the water column that drifts down to the depths. This dead and decaying matter sustains the benthic food chain ; most organisms in the benthic zone are scavengers or detritivores . Some microorganisms use chemosynthesis to produce biomass . Benthic organisms can be divided into two categories based on whether they make their home on

3871-538: The facial region. A circumpolar group of several species (the blue-eyed shag complex) is characterised by bright blue orbital skin. Prior to 2021, the IOU (or formerly the IOC) classified all these species in just three genera: Microcarbo , Leucocarbo , and a broad Phalacrocorax containing all remaining species; however, this treatment rendered Phalacrocorax deeply paraphyletic with respect to Leucocarbo . Other authorities, such as

3950-454: The family commonly encountered in Britain and Ireland and "cormorant" and "shag" appellations have been later assigned to different species in the family somewhat haphazardly. Cormorants and shags are medium-to-large birds, with body weight in the range of 0.35–5 kilograms (0.77–11.02 lb) and wing span of 60–100 centimetres (24–39 in). The majority of species have dark feathers. The bill

4029-535: The family into two genera and attach the name "cormorant" to one and "shag" to the other, but this nomenclature has not been widely adopted. Cormorants and shags are medium-to-large seabirds . They range in size from the pygmy cormorant ( Microcarbo pygmaeus ), at as little as 45 cm (18 in) and 340 g (12 oz), to the flightless cormorant ( Nannopterum harrisi ), at a maximum size 100 cm (39 in) and 5 kg (11 lb). The recently extinct spectacled cormorant ( Urile perspicillatus )

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4108-590: The great cormorant lack. As other species were encountered by English-speaking sailors and explorers elsewhere in the world, some were called cormorants and some shags, sometimes depending on whether they had crests or not. Sometimes the same species is called a cormorant in one part of the world and a shag in another; for example, all species in the family which occur in New Zealand are known locally as shags, including four non-endemic species known as cormorant elsewhere in their range. Van Tets (1976) proposed to divide

4187-545: The ground or in trees. Males collect most of the nest material, while both sexes share construction tasks. The nests are used twice a year in Autumn and Spring by different breeding pairs. Some breeding occurs in summer and winter by young and inexperienced pairs. Monogamous breeding pairs (from 2 years of age) lay eggs once a year with an average breeding cycle of 6 months. Clutch size ranges from 2–5 with an incubation period of 25–33 days. Egg and fledgling caring duties are shared by

4266-451: The highest flight costs of any flying bird. Cormorants nest in colonies around the shore, on trees, islets or cliffs. They are coastal rather than oceanic birds, and some have colonised inland waters. The original ancestor of cormorants seems to have been a fresh-water bird. They range around the world, except for the central Pacific islands. "Cormorant" is a contraction probably derived from Latin corvus marinus , "sea raven". Cormoran

4345-468: The late Paleogene, when the family presumably originated, much of Eurasia was covered by shallow seas, as the Indian Plate finally attached to the mainland. Lacking a detailed study, it may well be that the first "modern" cormorants were small species from eastern, south-eastern or southern Asia, possibly living in freshwater habitat, that dispersed due to tectonic events. Such a scenario would account for

4424-403: The layer of air next to the skin. The wing drying action is seen even in the flightless cormorant but not in the Antarctic shags or red-legged cormorants. Alternate functions suggested for the spread-wing posture include that it aids thermoregulation or digestion, balances the bird, or indicates presence of fish. A detailed study of the great cormorant concludes that it is without doubt to dry

4503-457: The most extreme case be reduced to the great , white-breasted and Japanese cormorants . In 2014, a landmark study proposed a 7 genera treatment, which was adopted by the IUCN Red List and BirdLife International , and later by the IOC in 2021, standardizing it. The cormorants and the darters have a unique bone on the back of the top of the skull known as the os nuchale or occipital style which

4582-411: The ocean floor or a few centimeters into the ocean floor. Those living on the surface of the ocean floor are known as epifauna . Those who live burrowed into the ocean floor are known as infauna . Extremophiles, including piezophiles , which thrive in high pressures, may also live there. An example of benthos organism is Chorismus antarcticus . Sources of food for benthic communities can derive from

4661-551: The other two European cormorant lineages, and as of 2022 still of mysterious ancestry ; notably, a presumably lost collection of Late Miocene fossils from the Odesa region may have contained remains of all three (sub)genera inhabiting Europe today. Similarly, the Plio-Pleistocene fossils from Florida have been allied with Nannopterum and even Urile , but may conceivably be Phalacrocorax ; they are in serious need of revision since it

4740-489: The parents. Chick rearing can take from 47–60 days with independence gained just over 3 months of age. Both sexes share feeding duties through incomplete regurgitation. Banding studies have shown that the pied cormorants do not travel far from their colonies (<20 km). Flight is generally low in altitude, as the pied cormorant has weaker flight capability than other species in the family, with 'v' formations present when in flocks. The Noongar Aboriginal people who live in

4819-462: The pelicans or even penguins , than to all other living birds. In recent years, three preferred treatments of the cormorant family have emerged: either to leave all living cormorants in a single genus, Phalacrocorax , or to split off a few species such as the imperial shag complex (in Leucocarbo ) and perhaps the flightless cormorant . Alternatively, the genus may be disassembled altogether and in

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4898-421: The plumage. Cormorants are colonial nesters, using trees, rocky islets, or cliffs. The eggs are a chalky-blue colour. There is usually one brood a year. Parents regurgitate food to feed their young. The genus Phalacrocorax , from which the family name Phalacrocoracidae is derived, is Latinised from Ancient Greek φαλακρός phalakros "bald" and κόραξ korax "raven". This is thought to refer to

4977-471: The potential mechanisms involving benthic periphyton and the effects on heterogeneity within a stream may provide a better understanding of the structure and function of stream ecosystems. Periphyton populations suffer from high natural spatial variability while difficult accessibility simultaneously limits the practicable number of samples that can be taken. Targeting periphyton locations which are known to provide reliable samples – especially hard surfaces –

5056-497: The present-day distribution of cormorants and shags and is not contradicted by the fossil record; as remarked above, a thorough review of the problem is not yet available. Even when Phalacrocorax was used to unite all living species, two distinct genera of prehistoric cormorants became widely accepted today: The proposed genus Oligocorax appears to be paraphyletic – the European species have been separated in Nectornis , and

5135-432: The sea (or food source). Courtship behaviour is initiated by the male in close proximity to a future nest site. Wing waving by the male is conducted in silence while gargling can be a form of female recognition. The males can also hop up to 1 m in the air with both feet to attract female attention. Nests are typically large platforms formed of sticks and foliage cemented with droppings averaging 80 cm in diameter on

5214-434: The sea floor. After fishing, cormorants go ashore, and are frequently seen holding their wings out in the sun. All cormorants have preen gland secretions that are used ostensibly to keep the feathers waterproof. Some sources state that cormorants have waterproof feathers while others say that they have water- permeable feathers. Still others suggest that the outer plumage absorbs water but does not permit it to penetrate

5293-664: The shallowest to the deepest are: the epipelagic (less than 200 meters), the mesopelagic (200–1,000 meters), the bathyal (1,000–4,000 meters), the abyssal (4,000–6,000 meters) and the deepest, the hadal (below 6,000 meters). The lower zones are in deep, pressurized areas of the ocean. Human impacts have occurred at all ocean depths, but are most significant on shallow continental shelf and slope habitats. Many benthic organisms have retained their historic evolutionary characteristics. Some organisms are significantly larger than their relatives living in shallower zones, largely because of higher oxygen concentration in deep water. It

5372-476: The south-west corner of Western Australia believe that the pied cormorant ( medi ) is responsible for the transport of souls of the deceased across and beneath the Western sea to their final resting place ( Kurannup ). Medi can be translated as 'agent', or 'medium', possibly referring to the bird's role as an intermediary between the living world and the afterlife. Spirits of the deceased rest for an unspecified time on

5451-468: The south-west, particularly along the coast. Its federal conservation status is 'secure' and only changes to 'near threatened' in Victoria. It can be found in all states except Tasmania. The pied cormorant has been calculated to be at high-moderate risk from fishing – particularly from set and inshore drift nets. Birds in colonies can often be observed entangled in recreational fishing line with hooks embedded in

5530-458: The surface, though many species make a characteristic half-jump as they dive, presumably to give themselves a more streamlined entry into the water. Under water they propel themselves with their feet, though some also propel themselves with their wings (see the picture, commentary, and existing reference video ). Imperial shags fitted with miniaturized video recorders have been filmed diving to depths of as much as 80 metres (260 ft) to forage on

5609-574: The surface. Risk of predation by sharks and the abundance of food comprise a trade-off where the pied cormorant may choose to hunt in deeper waters where prey is less abundant if the risk is too high during warmer months when sharks are present more often. The deeper waters however require longer dive times and corresponding longer times at rest between dives on the surface. The pied cormorant preferably breeds in small (<30 pairs) sheltered colonies (harbours, estuaries and lakes) with rarer occurrences on exposed coasts or islands, no more than 400 metres from

5688-418: The upper parts of the water column: the pressure difference can be very significant (approximately one atmosphere for each 10 meters of water depth). Many have adapted to live on the substrate (bottom). In their habitats they can be considered as dominant creatures, but they are often a source of prey for Carcharhinidae such as the lemon shark . Because light does not penetrate very deep into ocean-water,

5767-404: The water column above these habitats in the form of aggregations of detritus , inorganic matter, and living organisms. These aggregations are commonly referred to as marine snow , and are important for the deposition of organic matter, and bacterial communities. The amount of material sinking to the ocean floor can average 307,000 aggregates per m per day. This amount will vary on the depth of

5846-551: The water. The birds seem unaffected by variable salinity, turbidity and shoreline vegetation provided there are available perches. The pied cormorant appears to feed largely (90%) on benthic fish 6–15 cm in length from waters less than 10m deep. King George Whiting juveniles are known to be eaten. Other dietary components (10%) are made up of crustaceans such as prawns and shrimp with some molluscs and cephalopods. It will dive both in shallow, still water and in rapidly moving currents. Typical dive times are around 40 seconds, with

5925-404: Was called a xiphoid process in early literature. This bony projection provides anchorage for the muscles that increase the force with which the lower mandible is closed. This bone and the highly developed muscles over it, the M. adductor mandibulae caput nuchale, are unique to the families Phalacrocoracidae and Anhingidae. Several evolutionary groups are still recognizable. However, combining

6004-612: Was found in the Nemegt Formation in Mongolia; it is now in the PIN collection. It is from a bird roughly the size of a spectacled cormorant, and quite similar to the corresponding bone in Phalacrocorax . A Maastrichtian (Late Cretaceous, c. 66 mya) right femur , AMNH FR 25272 from the Lance Formation near Lance Creek, Wyoming , is sometimes suggested to be the second-oldest record of

6083-661: Was not yet ice-covered—all that can be said about the Phalacrocoracines is that they are most diverse in the regions bordering the Indian Ocean, but generally occur over a large area. Similarly, the origin of the family is shrouded in uncertainties. Some Late Cretaceous fossils have been proposed to belong with the Phalacrocoracidae: A scapula from the Campanian - Maastrichtian boundary, about 70 mya (million years ago),

6162-616: Was practised in Ancient Egypt, Peru, Korea and India, but the strongest tradition has remained in China and Japan, where it reached commercial-scale level in some areas. In Japan, cormorant fishing is called ukai ( 鵜飼 ) and is performed by a fisherman known as an usho. Traditional forms of ukai can be seen on the Nagara River in the city of Gifu , Gifu Prefecture , where cormorant fishing has continued uninterrupted for 1300 years, or in

6241-470: Was rather larger, at an average size of 6.3 kg (14 lb). The majority, including nearly all Northern Hemisphere species, have mainly dark plumage , but some Southern Hemisphere species are black and white, and a few (e.g. the spotted shag of New Zealand) are quite colourful. Many species have areas of coloured skin on the face (the lores and the gular skin ) which can be bright blue, orange, red or yellow, typically becoming more brightly coloured in

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