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Darlington Dam

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60-592: Darlington Dam , also referred to as Lake Mentz , is a gravity type dam situated in the Addo Elephant National Park confining the Sundays River , near Kirkwood , in the Eastern Cape , South Africa . The primary objective of building the dam was to provide adequate and perennial supplies of water for large-scale irrigation in a fertile area, particularly by storing and controlling flood waters. By 1917,

120-553: A brief description, coined the binomial name Diomedea demersa and cited Edwards' work. The African penguin is now placed with the banded penguins in the genus Spheniscus that was introduced in 1760 by the French zoologist Mathurin Jacques Brisson . The genus name Spheniscus is from Ancient Greek word σφήν ( sphēn ) meaning "wedge" and is a reference to the animal's thin, wedge-shaped flippers. The specific epithet demersus

180-456: A diet of anchovies appears to be generally sufficient for the penguins, it is not ideal due to anchovies' lower concentrations of fat and protein. The Penguin's diet changes throughout the year; as in many seabirds, it is believed that the interaction of diet choice and breeding success helps the penguins maintain their population size. Although parent penguins are protective of their chicks, they will not incur nutritional deficits themselves if food

240-621: A few days before a collecting effort to ensure that only freshly laid eggs were sold. This added to the drastic decline of the African penguin population around the Cape coast, a decline which was hastened by the removal of guano from islands for use as fertiliser, eliminating the burrowing material used by penguins. Penguins remain susceptible to pollution of their habitat by petrochemicals from spills, shipwrecks and cleaning of tankers while at sea. Accounts of African penguins impacted by oil date back to

300-519: A large variety of other marine life . Bird Island is home to the world's largest breeding colony of gannets - about 120,000 birds - and also hosts the second largest breeding colony of African penguins , the largest breeding colony being St. Croix island. These marine assets form part of the plan to expand the 1,640 km Addo National Elephant Park into the 3,600 km Greater Addo Elephant National Park . The expanded park contains five of South Africa's seven major vegetation zones ( biomes ), and

360-446: A male-biased adult sex ratio and may indicate that conservation strategies focused on benefiting female African penguins may be necessary. The average lifespan of an African penguin is 10 to around 25 years in the wild and up to 30 in captivity. The primary predators of African penguins at sea include sharks and fur seals . While nesting: kelp gulls , Cape genets , mongooses , caracals and domestic cats and dogs may prey on

420-482: A similar bar marking that often confuses the two; the Magellanic has a double bar on the throat and chest, whereas the African has a single bar. These penguins have the nickname "jackass penguin", which comes from the loud penguin noises they make. The African penguin is only found on the southwestern coast of Africa, living in colonies on 24 islands between Namibia and Algoa Bay , near Port Elizabeth , South Africa. It

480-691: Is Latin meaning "plunging" (from demergere meaning "to sink"). Banded penguins are found mainly in the Southern Hemisphere with the Humboldt penguin and Magellanic penguins found in southern South America and the Galápagos penguin found in the Pacific Ocean near the equator. All are similar in shape, colour and behaviour. African penguins grow to 60–70 cm (24–28 in) tall and weigh between 2.2–3.5 kg (4.9–7.7 lb). The beak length of

540-540: Is a diverse wildlife conservation park situated close to Gqeberha in South Africa and is one of the country's 20 national parks . It currently ranks third in size after Kruger National Park and the Kgalagadi Transfrontier Park . The original section of the park was founded in 1931, in part due to the efforts of Sydney Skaife , in order to provide a sanctuary for the eleven remaining elephants in

600-454: Is a species of penguin confined to southern African waters. Like all penguins, it is flightless , with a streamlined body and wings stiffened and flattened into flippers for a marine habitat. Adults weigh an average of 2.2–3.5 kg (4.9–7.7 lb) and are 60–70 cm (24–28 in) tall. The species has distinctive pink patches of skin above the eyes and a black facial mask. The body's upper parts are black and sharply delineated from

660-446: Is also the only park to house Africa's "Big 7" ( elephant , rhinoceros , lion , buffalo , leopard , whale and great white shark ) in their natural habitat . The flora within the AENP is quite varied, and like all plant life, is a central factor to the ecological system in place. Several species of rare and endemic plants, particularly succulent shrubs and geophytes are native to

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720-490: Is in Namibia, but it is not known when it was established. Boulders Beach is a tourist attraction due to the beach, swimming and the penguins. The penguins will allow people to approach them as close as a meter. Breeding populations of African penguins are being kept in numerous zoos worldwide. No colonies are known outside the southwestern coast of Africa, although vagrants (mostly juveniles) may occasionally be sighted beyond

780-752: Is one of the species to which the African-Eurasian Waterbird Agreement (AEWA) applies. In September 2010, it was listed as endangered under the US Endangered Species Act . As of 2024, the African penguin is listed as critically endangered on the IUCN Red List , with the remaining mature individuals around 19,800 birds in a declining population. Many organisations such as SANCCOB , Dyer Island Conservation Trust, SAMREC , The National Aviary in Pittsburgh, and Raggy Charters with

840-450: Is scarce and hunting requires a greater time or energy commitment. This may lead to higher rates of brood loss under poor food conditions. When foraging, African penguins carry out dives that reach an average depth of 25 m (82 ft) and last for 69 seconds, although a maximum depth of 130 m (430 ft) and duration of 275 seconds has been recorded. The African penguin is monogamous ; it breeds in colonies and pairs return to

900-672: Is the only penguin species that breeds in Africa and its presence gave name to the Penguin Islands . Two colonies were established by penguins in the 1980s on the mainland near Cape Town, namely Boulders Beach near Simon's Town and Stony Point in Betty's Bay . Mainland colonies likely became possible only in recent times due to the reduction of predator numbers, although the Betty's Bay colony has been attacked by leopards . The only other mainland colony

960-418: Is threatening the flora, but a number of other ecological factors including zoochory and nutrient cycling . Up to 77 species of South African endemic plant species have been listed as "vulnerable to elephant browsing." The Addo Elephant National Park Marine Protected Area and Bird Island Marine Protected Area are associated with the park. In 2018 the highest visitor count in the park's 87-year history

1020-466: The Treasure oil spill, the species is considered a good "candidate for a captive-breeding programme which aims to release offspring into the wild"; however, worry about the spread of new strains of avian malaria is a major concern in the situation. Bringing the birds inland led to the exposure of penguins to parasites and disease vectors such as mosquitoes carrying avian malaria, which has caused 27% of

1080-643: The University of Cape Town 's FitzPatrick Institute of African Ornithology found that rehabilitating oiled African penguins has resulted in the current population being 19% larger than it would have been in the absence of SANCCOB's rehabilitation efforts. In February 2015, the Dyer Island Conservation Trust opened the African Penguin and Seabird Sanctuary (APSS) in Gansbaai , South Africa. The centre

1140-673: The pumping of bilges at sea had killed tens of thousands of African penguins. At the time, the Dassen Island colony was being passed by 650 oil tankers each month because the Suez Canal had become blocked with wrecked vessels, thus increasing maritime traffic past the Cape of Good Hope. In 1979, an oil spill prompted the collection and treatment of 150 African penguins from St. Croix Island near Port Elizabeth. The animals were later released at Robben Island and four of them promptly swam back to St. Croix Island, surprising scientists. In 1983,

1200-406: The 1930s. African penguins' exposure to oil spills is both chronic (higher frequency small discharges of oil at sea) and acute (rare maritime disasters where large volumes of oil are released in a single event). Penguins of many species have been impacted by oil spills across the southern hemisphere. In 1948, the tanker Esso Wheeling sank, subsequently oiling and killing thousands of penguins of

1260-402: The African penguin varies, usually growing between 20–30 cm (7.9–11.8 in). They have a black stripe and black spots on the chest, the pattern of which is unique to each penguin, like human fingerprints. The sweat glands above the eyes cool the birds' blood and as the temperature rises, increased blood flow causes the glands to get pinker. This species exhibits slight sexual dimorphism ;

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1320-628: The Boulders Beach colony being an exception to this rule. The total population fell to approximately 150,000–180,000 in 2000. Of those, 56,000 belonged to the Dassen Island colony and 14,000 to the Robben Island colony. The colony at Dyer Island in South Africa fell from 46,000 in the early 1970s to 3,000 in 2008. In 2008, 5,000 breeding pairs were estimated to live in Namibia. In 2010,

1380-479: The Conservation of Coastal Birds (SANCCOB) and took more than three months to complete. This was the largest animal rescue event in history; more than 91% of the penguins were successfully rehabilitated and released – an amazing feat that could not have been accomplished without such a tremendous international response. Due to the positive outcome of African penguins being raised in captivity after tragedies such as

1440-627: The Dyer Island colony. In 1953, dead penguins were among a range of dead birds, fish and other marine life that washed ashore after the tanker Sliedrecht was holed and spilled oil near Table Bay . In 1971, the SS Wafra oil spill impacted the African penguin colony of Dyer Island. In 1972, oil spilt following the Oswego-Guardian and Texanita collision oiled roughly 500 penguins. In 1975, newspapers reported that oil pollution from shipwrecks and

1500-583: The English name "The Black-Footed Penguins". Edwards based his hand-coloured etching on two preserved specimens that had been brought to London . He suspected that they had been collected near the Cape of Good Hope . When in 1758 the Swedish naturalist Carl Linnaeus updated his Systema Naturae for the tenth edition , he placed the African penguin with the wandering albatross in the genus Diomedea . Linnaeus included

1560-546: The Penguin Research Fund in Port Elizabeth are working to halt the decline of the African penguin. Measures include: monitoring population trends, hand-rearing and releasing abandoned chicks, establishing artificial nests and proclaiming marine reserves in which fishing is prohibited. Some colonies (such as on Dyer Island ) are suspected to be under heavy pressure from predation by Cape fur seals and may benefit from

1620-458: The South African region within the AENP. Many species are under environmental pressure, however, and are facing possible extinction. The park is home to more than 600 elephants, 400 Cape buffaloes , over 48 endangered south-western black rhinoceros' (Diceros bicornis occidentalis) as well as a variety of antelope species. Lion and spotted hyena have also recently been re-introduced to

1680-583: The Sundays River Irrigation Board was established and took over the project from the government's Irrigation Department in 1918. The construction experienced many setbacks, including lack of materials and machinery, with shortages caused by the First World War, unsuitable labour (returning soldiers), the 1918 influenza epidemic , bubonic plague, very difficult logistics and drought. The delays in completion caused severe financial difficulties to

1740-567: The area. The largest remaining population of the flightless dung beetle ( Circellium bacchus ) is located within the park. Two major environmental issues facing the AENP: extinction and overpopulation , which are interrelated. Since the AENP's original mission was to reintroduce certain megaherbivores , like the African bush elephant and eastern black rhinoceros , primary ecological efforts were made to preserve mammalian species. However, by overlooking

1800-497: The area. The park has proved to be very successful and currently houses more than 600 elephants and a large number of other mammals. The original park has subsequently been expanded to include the Woody Cape Nature Reserve that extends from the Sundays River mouth towards Alexandria and a marine reserve, which includes St. Croix Island and Bird Island , both breeding habitat for gannets and penguins , as well as

1860-547: The birds are difficult to spot by predators under the water and the penguins' black backs blend in with the water when viewed from above. African penguins resemble and are thought to be related to the Humboldt, Magellanic and Galápagos penguins. African penguins have a very recognisable appearance, with a thick band of black that is in the shape of an upside-down horseshoe. They have black feet and black spots that vary in size and shape between individuals. Magellanic penguins share

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1920-455: The chicks join a crèche with other chicks and both parents spend most of the day foraging in the sea. Chicks fledge at 60 to 130 days, the timing depending on environmental factors such as the quality and availability of food. The fledged chicks then go to sea on their own, where they spend the next one to nearly two years. They then return to their natal colony to moult into adult plumage. When penguins moult , they are unable to forage in

1980-511: The culling of individual problem animals, which has been found effective (although requiring a large amount of management effort) in trials. Established in 1968, SANCCOB is currently the only organisation mandated by the South African government to respond to crises involving seabirds along South Africa's coastline and is internationally recognised for the role it played during the MV Treasure oil spill. A modelling exercise conducted in 2003 by

2040-507: The day while the parents forage. The chicks are frequently killed by predators or succumb to the hot sun. Parents usually feed hatchlings during dusk or dawn. In 2015, when foraging conditions were favourable, more male than female African penguin chicks were produced in the colony on Bird Island. Male chicks also had higher growth rates and fledging mass and therefore may have higher post-fledging survival than females. This, coupled with higher adult female mortality in this species, may result in

2100-630: The demand for water in the Port Elizabeth metropolitan area, it was decided to replace the Wellington Grove pumping station with De Mistkraal Weir upstream of Wellington Grove and a short section of connecting canal to the beginning of the Skoenmakers Canal. This article about a dam or floodgate in South Africa is a stub . You can help Misplaced Pages by expanding it . Addo Elephant National Park Addo Elephant National Park (AENP)

2160-456: The eggs are incubated in a burrow dug into the guano layer (which provides suitable temperature regulation), but the widespread human removal of guano deposits has rendered this type of nest unfeasible in many colonies. To compensate, penguins burrow holes in the sand, nest under rocks or bushes or make use of nest boxes if they are provided. The penguins spend three weeks on land caring for their offspring, after which chicks may be left alone during

2220-597: The exposure of penguins of Dassen Island to the oil slick from the Castillo de Bellver was also a topic of concern given the penguins' conservation status at the time, but owing to the prevailing wind and current, only gannets were oiled. African penguin casualties were significant following the sinking of the MV Apollo Sea and a subsequent oil slick in 1994. 10,000 penguins were collected and cleaned, of which less than half survived. Disaster struck on 23 June 2000, when

2280-705: The iron ore tanker MV Treasure sank between Robben Island and Dassen Island , South Africa. It released 400–1,000 tonnes (390–980 long tons; 440–1,100 short tons) of fuel oil, causing an unprecedented coastal bird crisis and oiling 19,000 adult penguins at the height of the best breeding season on record for this vulnerable species. The oiled birds were brought to an abandoned train repair warehouse in Cape Town to be cared for. An additional 19,500 un-oiled penguins were removed from Dassen Island and other areas before they became oiled and were released about 800 kilometres east of Cape Town. This gave workers enough time to clean up

2340-526: The irrigation companies and eventually the State had to take over the debts of the irrigators and £2,350,000 had to be written off. It was completed in 1922 and only filled by 1928, the delay a result of extensive drought. The original dam was designed to store 142 million m. The high sediment yield of the Sundays River meant that sediment delivery into the reservoir basin quickly reduced its capacity. The dam wall

2400-421: The late 1950s, some French chefs expressed interest in recipes including African penguin eggs collected from the islands off the west coast of South Africa and placed annual orders for small quantities. In the mid-1960s, eggs were collected in the thousands and sold by the dozen, with each customer limited to two dozen eggs in total. The practice of collecting African penguin eggs involved smashing those found

2460-413: The mainland, African penguins will seek protection on offshore islands, where they are safer from larger mammals and natural challenges. These penguins usually breed during the winter when temperatures are cooler. African penguins often will abandon their eggs if they become overheated in the hot sun and abandoned eggs never survive the heat. The eggs are three to four times bigger than chicken eggs. Ideally,

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2520-441: The males are slightly larger than the females and have longer beaks. Juveniles do not possess the bold, delineated markings of the adult, but instead have dark upperparts that vary from greyish-blue to brown; the pale underparts lack both spots and the band. The beak is more pointed than that of the Humboldt penguin . The African penguin's colouring is a form of protective colouration known as countershading . The white undersides of

2580-437: The normal range. Roughly 4 million African penguins existed at the beginning of the 19th century. Of the 1.5 million African penguins estimated in 1910, only some 10% remained at the end of the 20th century. African penguin populations, which breed in Namibia and South Africa, have declined by 95% since pre-industrial times. Today, their breeding is largely restricted to 24 islands from Namibia to Algoa Bay, South Africa, with

2640-552: The oiled waters and shores before the birds could complete their long swim home (which took the penguins between one and three weeks). Some of the penguins were named and radio-tracked as they swam back to their breeding grounds. Tens of thousands of volunteers helped with the rescue and rehabilitation process, which was overseen by the International Fund for Animal Welfare (IFAW) and the South African Foundation for

2700-507: The open sea, where they feed on pelagic fish such as sardines (including the blue pilchard ), Cape horse mackerels , red-eye round herrings and anchovies (specifically the European anchovy and the Southern African anchovy ) and marine invertebrates such as squids and small crustaceans , primarily krills and shrimps . Penguins normally swim within 20 km (12 mi) of

2760-408: The other contributors to this environmental chain, certain plant species have been subjected to overgrazing and trampling, mostly by the elephants of the park. This overgrazing and trampling not only destroys much of the plant life, but also forces it to adapt its physiology to stimuli that are not inherent to its evolutionary progress. Some biologists argue that it is not herbivorization alone that

2820-503: The park are tarred while the others are graveled. There is also an additional access road through the southern block of the park feeding off the N2 highway near Colchester ; it joins up with the existing tourist roads in the park. African penguin Diomedea demersa Linnaeus, 1758 The African penguin ( Spheniscus demersus ), also known as Cape penguin or South African penguin ,

2880-428: The penguins and their chicks. Mortality from terrestrial predators is higher if penguins are forced to breed in the open in the absence of suitable burrows or nest boxes. African penguin eggs were considered a delicacy and were still being eaten and collected for sale as recently as the 1970s. In the 1950s, they were being collected from Dassen Island and sold in nearby towns. In 1953, 12,000 eggs were collected. In

2940-625: The rehabilitated penguin deaths annually. Small-scale oil spills (of less than 400 litres (110 US gal)) have occurred at the Port of Ngqura since bunkering activities started there in 2016. Bunkering is a ship refuelling process that can result in oil spills and oil slicks entering the water. Hundreds of African penguins have been harmed following these spills due to the port's close proximity to penguin rookeries on St. Croix Island and seabird habitat on neighbouring Jahleel and Brenton Islands. Commercial fisheries of sardines and anchovy ,

3000-414: The same site each year. It has an extended breeding season, with nesting usually peaking from March to May in South Africa and November to December in Namibia. A clutch of two eggs is laid either in burrows burrowed in guano or nests in the sand under boulders or bushes. Incubation is undertaken equally by both parents for around 40 days. At least one parent guards the chicks for about one month, whereafter

3060-427: The sea as their new feathers are not yet waterproof; therefore, they fast over the entire moulting period. African penguins typically take around three weeks to moult and lose about half of their body weight by burning up their fat reserves in the process. African penguins spend most of their lives at sea until it comes time for them to lay their eggs. Females remain fertile for about 10 years. Due to high predation on

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3120-437: The shore. A penguin may consume up to 540 grams (1.19 lb) of prey every day, but this may increase to over 1 kg (2.2 lb) when raising older chicks. Due to the marked decline of sardines in the waters near its habitat, African penguins' diet has shifted towards anchovies to some extent, although available sardine biomass is still a notable determinant of penguin population development and breeding success. While

3180-455: The species include black-footed penguin and jackass penguin , due to the species' loud, donkey-like noise (although several related species of South American penguins produce the same sound). They can be found along the coast of South Africa and Namibia . In 1747, the English naturalist George Edwards included an illustration and a description of the African penguin in the second volume of his A Natural History of Uncommon Birds . He used

3240-517: The total African penguin population was estimated at 55,000. At the rate of decline seen from 2000 to 2010, the African penguin is expected to be extinct in the wild by 2026. In 2012, about 18,700 breeding pairs were estimated to live in South Africa, with the majority on St. Croix Island in Algoa Bay . The total breeding population across both South Africa and Namibia fell to a historic low of about 20,850 pairs in 2019. African penguins forage in

3300-426: The two main prey species of the penguins, have forced these penguins to search for prey farther offshore, as well as having to switch to eating less nutritious prey. Restricting commercial fishing near colony sites such as Robben Island for short periods (3 years) was shown to markedly improve penguin breeding success. Longer closure periods and closures near other colonies are being evaluated. The African penguin

3360-539: The wall. The impoundment now has a capacity of 187,000,000 cubic metres (6.6 × 10 cu ft), with a 35.3 metres (116 ft)-high wall. Its primary purpose is for irrigation, industrial and domestic use. The serious drought of 1966 and 1967 emphasized the necessity to commence work on the Skoenmakers Canal (capacity: 22 m/s) to link the Great Fish River to Darlington Dam as soon as possible. In view of an expected increase in irrigation below Darlington Dam and

3420-437: The white underparts, which are spotted and marked with a black band. The African penguin is a pursuit diver and feeds primarily on fish and squid. Once extremely numerous, the African penguin is now the rarest species of penguin classified as critically endangered , with its population declining rapidly due to a combination of several threats. It is a charismatic species and is popular with tourists. Other vernacular names of

3480-614: Was opened by then- Department of Tourism minister Derek Hanekom and will serve as a hub for seabird research carried out by the Dyer Island Conservation Trust. The centre will also run local education projects, host international marine volunteers and seek to improve seabird handling techniques and rehabilitation protocols. African penguins are a commonly seen species in zoos across the world. Because they do not require particularly low temperatures, they are often kept in outside enclosures. They adapt fairly well to this captive environment and are rather easy to breed compared to other species of

3540-506: Was raised by 1.5 m in 1935 and again by 5.8 m (total capacity 327,628,072 m) in 1951/52 to cope with the loss of storage volume. The rebuilt dam was opened on 26 April 1952, by the then Minister of Land and Irrigation, J. G. Strijdom , with work supervised by the Sundays River Irrigation Board, with J. Kevin Murphy as the consulting engineer. By 1979 the reservoir had lost 41.47% of its design capacity, with ~135,870,000 m of sediment captured behind

3600-474: Was recorded. The park received 305,510 visitors between 1 April 2017 and 31 March 2018 (up from 265,585 in the previous year). International visitors make up 55% of this number, with German , Dutch and British nationals in the majority. There is a main camp, featuring a swimming pool, restaurant, flood lit water hole and various accommodation, four other rest camps and four camps run by concessionaires. The main entrance as well as two looped tourist roads in

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