Wikipedia

African penguin

(Redirected fromSpheniscus demersus)

TheAfrican penguin(Spheniscus demersus), also known asCape penguinorSouth African penguin,is a species ofpenguinconfined to southernAfricanwaters. Like all penguins, it isflightless,with a streamlined body and wings stiffened and flattened intoflippersfor 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 the white underparts, which are spotted and marked with a black band.

African penguin
AtBoulders BeachinSimon's Town,South Africa
CITESAppendix II(CITES)[2]
Scientific classificationEdit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Sphenisciformes
Family: Spheniscidae
Genus: Spheniscus
Species:
S. demersus
Binomial name
Spheniscus demersus
Map
IUCN range (2024)
Extant (resident)
Extant (non-breeding)
Extant (breeding)
Extant & Reintroduced (breeding)
Distribution of the African penguin
Synonyms

Diomedea demersaLinnaeus, 1758

The African penguin is apursuit diverand feeds primarily on fish and squid. Once extremely numerous, the African penguin is now the rarest species of penguin classified ascritically endangered,with its population declining rapidly due to a combination of several threats. It is a charismatic species and is popular with tourists. Othervernacular namesof the species includeblack-footed penguinandjackass penguin,due to the species' loud, donkey-like noise[3](although several related species of South American penguins produce the same sound). They can be found along the coast ofSouth AfricaandNamibia.

Taxonomy

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In 1747, the English naturalistGeorge Edwardsincluded an illustration and a description of the African penguin in the second volume of hisA Natural History of Uncommon Birds.He used the English name "The Black-Footed Penguins". Edwards based his hand-coloured etching on two preserved specimens that had been brought toLondon.He suspected that they had been collected near theCape of Good Hope.[4]When in 1758 the Swedish naturalistCarl Linnaeusupdated hisSystema Naturaefor thetenth edition,he placed the African penguin with thewandering albatrossin thegenusDiomedea.Linnaeus included a brief description, coined thebinomial nameDiomedea demersaand cited Edwards' work.[5]The African penguin is now placed with the banded penguins in the genusSpheniscusthat was introduced in 1760 by the French zoologistMathurin Jacques Brisson.[6][7]The genus nameSpheniscusis fromAncient Greekwordσφήν(sphēn) meaning "wedge" and is a reference to the animal's thin, wedge-shaped flippers. The specific epithetdemersusisLatinmeaning "plunging" (fromdemergeremeaning "to sink" ).[8]

Banded penguins are found mainly in the Southern Hemisphere with theHumboldt penguinandMagellanic penguinsfound in southern South America and theGalápagos penguinfound in the Pacific Ocean near the equator. All are similar in shape, colour and behaviour.

Penguin colony atBetty's Bay

Description

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African penguin diving inSiam Center,Bangkok,Thailand
African penguin skeleton at theMuseum of OsteologyinOklahoma City,Oklahoma,USA

African penguins grow to 60–70 cm (24–28 in) tall and weigh between 2.2–3.5 kg (4.9–7.7 lb).[9]The beak length of 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.[10]This species exhibits slightsexual dimorphism;the males are slightly larger than the females and have longer beaks.[11]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 theHumboldt penguin.The African penguin's colouring is a form of protective colouration known ascountershading.The white undersides of 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,MagellanicandGalápagospenguins.[12]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 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.

Distribution and habitat

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The African penguin is only found on the southwestern coast of Africa, living in colonies on 24 islands between Namibia andAlgoa Bay,nearPort Elizabeth,South Africa.[13]It is the only penguin species that breeds in Africa and its presence gave name to thePenguin Islands.

Penguin with chicks,Boulders Beach,South Africa

Two colonies were established by penguins in the 1980s on the mainland near Cape Town, namelyBoulders BeachnearSimon's Townand Stony Point inBetty'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 byleopards.[14][15]The only other mainland colony 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.[16][17]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, althoughvagrants(mostly juveniles) may occasionally be sighted beyond the normal range.

Population

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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.[18]

Today, their breeding is largely restricted to 24 islands from Namibia to Algoa Bay, South Africa,[19]with the Boulders Beach colony being an exception to this rule.

The total population fell to approximately 150,000–180,000 in 2000.[20][21]Of those, 56,000 belonged to theDassen Islandcolony and 14,000 to theRobben Islandcolony.[22]The colony atDyer Islandin South Africa fell from 46,000 in the early 1970s to 3,000 in 2008.[23]

In 2008, 5,000 breeding pairs were estimated to live in Namibia.

In 2010, 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.[24]

In 2012, about 18,700 breeding pairs were estimated to live in South Africa, with the majority onSt. Croix IslandinAlgoa Bay.[13][25]

The total breeding population across both South Africa and Namibia fell to a historic low of about 20,850 pairs in 2019.[26]

Behaviour

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Diet

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African penguins forage in the open sea, where they feed onpelagic fishsuch assardines(including theblue pilchard),Cape horse mackerels,red-eye round herrings[27]andanchovies(specifically theEuropean anchovyand theSouthern African anchovy)[28][27]and marine invertebrates such assquidsand smallcrustaceans,primarilykrillsandshrimps.[29]Penguins normally swim within 20 km (12 mi) of the shore.[9]A penguin may consume up to 540 grams (1.19 lb) of prey every day,[30]but this may increase to over 1 kg (2.2 lb) when raising older chicks.[29]

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 sardinebiomassis still a notable determinant of penguin population development and breeding success. While 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 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.[31]

Breeding

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Egg from the collection ofMuseum Wiesbaden,Wiesbaden,Hesse,Germany
Nesting burrows of the African penguin,Boulders Beach(2017)

The African penguin ismonogamous;it breeds in colonies and pairs return to 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.[28]A clutch of two eggs is laid either in burrows burrowed inguanoor 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 the chicks join acrèchewith other chicks and both parents spend most of the day foraging in the sea.

Chicksfledgeat 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.[32]

When penguinsmoult,they are unable to forage in the sea as their new feathers are not yet waterproof; therefore, they fast over the entire moulting period.[32]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.[33]

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 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, 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 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 a male-biased adult sex ratio and may indicate that conservation strategies focused on benefiting female African penguins may be necessary.[34]

Predation

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The average lifespan of an African penguin is 10 to around 25 years in the wild and up to 30 in captivity.[35]

The primary predators of African penguins at sea includesharksandfur seals.While nesting:kelp gulls,Cape genets,mongooses,caracalsand domesticcatsanddogsmay prey on the penguins and their chicks.[36][37]Mortality from terrestrial predators is higher if penguins are forced to breed in the open in the absence of suitable burrows or nest boxes.

Threats and conservation

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African penguin at theNew England Aquarium,Boston,Massachusetts,United States of America
(video) African penguin swims in an aquarium inTokyo,Japan

Historical exploitation

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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 fromDassen Islandand sold in nearby towns.[38]In 1953, 12,000 eggs were collected.[39]In 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.[40][41][42]In the mid-1960s, eggs were collected in the thousands and sold by the dozen,[43]with each customer limited to two dozen eggs in total.[44]

The practice of collecting African penguin eggs involved smashing those found 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 ofguanofrom islands for use as fertiliser, eliminating the burrowing material used by penguins.[45]

Oil spills

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Penguins remain susceptible to pollution of their habitat bypetrochemicalsfrom spills, shipwrecks and cleaning of tankers while at sea. Accounts of Africanpenguins impacted by oildate back to the 1930s.[46]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 beenimpacted by oil spillsacross the southern hemisphere.

In 1948, the tankerEsso Wheelingsank, subsequently oiling and killing thousands of penguins of the Dyer Island colony.[47]In 1953, dead penguins were among a range of dead birds, fish and other marine life that washed ashore after thetankerSliedrechtwas holed and spilled oilnearTable Bay.[48]In 1971, theSSWafraoil spillimpacted the African penguin colony of Dyer Island. In 1972, oil spilt following theOswego-GuardianandTexanitacollision oiled roughly 500 penguins.[49]In 1975, newspapers reported that oil pollution from shipwrecks and thepumping of bilgesat 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[50]because theSuez Canalhad become blocked with wrecked vessels, thus increasing maritime traffic past the Cape of Good Hope.[49]

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.[51][52]

In 1983, the exposure of penguins of Dassen Island to the oil slick from theCastillo de Bellverwas also a topic of concern given the penguins' conservation status at the time, but owing to the prevailing wind and current, onlygannetswere oiled.[53]

1994 MVApollo Seadisaster

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African penguin casualties were significant following the sinking of theMVApollo Seaand a subsequent oil slick in 1994. 10,000 penguins were collected and cleaned, of which less than half survived.[54]

2000 MVTreasurecrisis

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Disaster struck on 23 June 2000, when the iron ore tankerMVTreasuresankbetweenRobben IslandandDassen 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.[55]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 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 andradio-trackedas they swam back to their breeding grounds. Tens of thousands of volunteers helped with the rescue and rehabilitation process, which was overseen by theInternational Fund for Animal Welfare(IFAW) and theSouth African Foundation for 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.[56]

Due to the positive outcome of African penguins being raised in captivity after tragedies such as theTreasureoil 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 ofavian malariais a major concern in the situation.[57]

Bringing the birds inland led to the exposure of penguins to parasites anddisease vectorssuch as mosquitoes carrying avian malaria, which has caused 27% of the rehabilitated penguin deaths annually.[58]

2016 & 2019 Port of Ngqura

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Small-scale oil spills (of less than 400 litres (110 US gal)) have occurred at thePort of Ngqurasincebunkeringactivities 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[59]due to the port's close proximity to penguinrookeriesonSt. Croix Islandand seabird habitat on neighbouring Jahleel and Brenton Islands.

Competition with fisheries

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Commercial fisheriesofsardinesandanchovy,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.[18]Restricting commercial fishing near colony sites such asRobben Islandfor short periods (3 years) was shown to markedly improve penguin breeding success. Longer closure periods and closures near other colonies are being evaluated.[60][61][62]

Conservation status

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The African penguin is one of the species to which theAfrican-Eurasian Waterbird Agreement(AEWA) applies. In September 2010, it was listed as endangered under the USEndangered Species Act.[18]As of 2024, the African penguin is listed ascritically endangeredon theIUCN Red List,with the remaining mature individuals around 19,800 birds in a declining population.[1]

Mediation efforts

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Many organisations such asSANCCOB,Dyer Island Conservation Trust,SAMREC,TheNational Aviaryin Pittsburgh, and Raggy Charters with 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.[1]Some colonies (such as onDyer Island) are suspected to be under heavy pressure from predation byCape fur sealsand may benefit from the culling of individual problem animals,[61][63]which has been found effective (although requiring a large amount of management effort) in trials.[64]

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 MVTreasureoil spill. A modelling exercise conducted in 2003 by theUniversity 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.[65]

In February 2015, the Dyer Island Conservation Trust opened the African Penguin and Seabird Sanctuary (APSS) inGansbaai,South Africa.[66]The centre was opened by then-Department of TourismministerDerek Hanekom[67]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.

Captivity

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African penguin at theDallas World Aquarium,Dallas,Texas,United States

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 the family. InEurope,the breeding programmeEAZAis regulated byArtis Royal Zooin theNetherlands,whilst in the United States theSSPprogramme is cooperatively managed by theAZA.The idea is to create a backup captive population, as well as to aid in the conservation of the population in its natural habitat. Between 2010 and 2013, American zoos spent $300,000 onin situ(wild population) conservation.[68][69]

See also

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  • Nesting African penguin
  • Colony of African penguins nesting on Boulders Beach in Cape Town
  • African penguins on Boulders Beach
  • African penguins on a rock at Boulders Beach
  • African penguin part of theBetty's Baycolony
  • Adult (front) and juvenile (back)

References

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