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Home , Cape Canary, Cape cormorant, Cape gannet, Cape wagtail, List of birds of Namibia

COASTAL There are 18 of penguins in the world and all of them are found in the Southern Hemisphere.

The penguins of our region travel on land by walking or hopping. They swim with great speed and agility. The flippers—wings—are their sole means of propulsion in the water; the feet are trailed behind or used in steering. Some species progress by ‘porpoising’, which involves swimming underwater for some distance, then emerging in a graceful arc to take a fresh breath, and submerging again. Penguins do not have normal feathers, as do most birds, but are covered almost uniformly with small, scale- like feathers. Penguins moult all of their feathers and, in some species, even shed the shields from the within a short space of time. A moulting has a dishevelled appearance; losing its feathers in huge patches as new feathers appears. During the moulting period, which may last several weeks, the penguin does not enter the water to feed. Feeding Penguins eat crustaceans, small and cephalopods. Their food is taken by pursuit diving even to depths of 100m. They appear to stun their prey first from below with a blow from their beak before swallowing it beneath the surface. Social behaviour Penguins have a number of social behaviours from head swaying, trumpeting, quivering, mutual preening, stone carrying, aggressive behaviour, submissive and appeasing behaviours. They also appear to find that fishing in groups is advantageous. Bonding and breeding The greatest concentrations of penguins are seen in rookeries, where the birds gather to breed. Some penguin pair’s bonds are maintained in successive seasons, but frequent changes in pairs have been noted even if both members are alive and present in a colony. Penguins vary in their nesting methods such as a scrape in the ground lined with pebbles, burrows or in small crevices caused by plant roots or rocks. They usually lay two eggs and normally only one chick survives. Roughly about 65% of all eggs laid do hatch and most of the chicks survive, as the parents are good guarders. In general, both sexes incubate the eggs and feed the young.

Most penguin chicks are covered with a sooty-grey down at hatching, although some have a pattern of soft greys and whites. Chicks of certain species remain confined to the burrow or nest throughout the entire nesting period, during which time their parents feed them. On their parents' return from fishing, parents and chicks recognize each other in a group often numbering thousands. In some cases there ensues a feeding chase in which the chick leaves the nursery to chase one of its food-laden parents. The parent finally stops and regurgitates partly digested food for the chick. After a young penguin has shed the last of its down and acquires its first , it enters the sea to fend for itself.

AFRICAN BLACKFOOTED PENGUIN (Spheniscus demersus) ENDANGERED

This penguin is the only species that breeds in mainly off . They are also endemic to this region. They were previously known as the Jackass penguin but are now formally known as the African Blackfooted Penguin. These penguins are now (June 2010) listed as an endangered species due to many factors. Up until 1967 collecting penguin eggs (approx. 13 million) reduced their numbers dramatically and that, coupled with smaller pilchard shoals, probably had the most major impact. Historically African Blackfooted penguins nested in their guano deposits. This changed when the fertiliser industry of the 1800’s boomed and guano deposits were scraped from their breeding grounds. This practice is now illegal but the damage has certainly been done as natural nesting sites have been lost. In recent times heavy oil spills along the west coast of , despite large-scale penguin capture and cleanup programmes, has resulted in further reduction in their numbers. During the Treasure oil spill (June 2000) almost 19,000 birds were collected for rehabilitation. Other reasons responsible for their decline are climate variation; shift in location of prey (W>E); fisheries interactions (competition & entanglement); coastal and inshore mining; disease; human disturbance. Due to the increased tourist interest and new protected breeding areas being designated along the coast (Boulders and Robben Island for example) efforts are being made to ensure their survival. The situation for this species, however, remains dire. In 1910 there were an estimated 1.5 million birds and, at last count, less than 60 000 birds remain. Between the years 2005-2010 the African Blackfooted penguin population halved.

FACTS OF INTEREST FOR AFRICAN BLACK FOOTED PENGUINS (ABFP)

1. Camouflage – black on their backs so as to blend in with the depths of the ocean floor. White on their bellies to blend in with the sun shining down from above. 2. ABFP are monogamous, they pick a partner for life. 3. Lay 2 eggs a few days apart and incubation is between 38 & 42 days with both parents being involved. Chicks hatch weight is around 72g. 4. The chicks fledge anywhere between 55-130 days. 5. Eggs hatch a few days apart and the first hatched will generally always be the stronger of the two. In the wild the weaker one will often die. (At Two Oceans Aquarium We weigh our chicks regularly to ensure that they are gaining approximately 10% of their body weight daily. In this way we know that the parents are doing a good job of looking after their offspring.) 6. Every moults (replaces all of their feathers) every year and grows a brand new black and white “suite”. During the moult, which lasts about 3 weeks, they remain on land as they are not waterproofed and cannot go to sea to feed. For this reason they gorge on fish just before the moult period and can sometimes double their body weight. This ensures they have enough reserves to keep them healthy until they are newly feathered and can once again venture to sea. 7. They their fish whole with the aid of hook-like protrusions on their tongues and down the back of their throats. As they swallow these hook into the fish and help it down 8. Penguins drink salt water and they are able to desalinate it in to get their fresh water requirements. This is done thru their nostrils and all sea birds are adapted this way. 9. Penguins have a very high metabolism and can eat many fish in a day. Generally they will eat 1-4, however in preparation for a moult they will gorge themselves and can eat anything up to 15 or more fish in a day. In the wild the birds remain on land for the moult period of about 3 weeks and they have to have built up enough fat reserves to see them thru this period of not eating. 10. Their appetite increases dramatically during the rearing of offspring too. 11. They can swim at speeds of 30km/hr at very short bursts when hunting. 12. In South African regions they feed on sardines & ; and in Namibian regions on goby, mackerel. 13. They have been known to reach depths of up to 130m but generally hunt at depths less than 80m with up to 20m being most common. They forage within 30-35kms of their breeding colonies. 14. In the wild eggs are laid Feb-Aug; chicks hatch April-Oct; moulting occurs Nov-Feb 15. Predators of the ABFP are: humans, ferel , gennets, seals, jackals, mongoose, dogs

ROCKHOPPER PENGUINS (Eudyptes chrysocome) These are Antarctic or sub-Antarctic penguins and although they are not endangered at present could easily become so. There is increasing pressure on the their land habitats for human access (eco-tourism) and other human activities whilst large fishing fleets now in those waters pose a threat as well. The mature Rockhoppers have short stubby red bills and pale yellow stripes in front of the eyes forming a long drooping and laterally projecting crests behind the eye. Immatures have shorter crest and smaller brown . Males are generally heavier than the female and the average weight is 2.8 to 3 kilograms for males and 2.3 to 2.7 kgs for a female. On land they can hop remarkably quickly with their feet together. Distribution of these penguins is mainly the sub-Antarctic regions and in summer they breed on about 16 islands including Marion and Prince Edward islands. Occasionally moulting juveniles are found on South African beaches between January and February. Predators Eggs, chicks and sickly penguins are often taken from the land nests by , northern giant or Norway . At sea, however seals hunt the adults. AFRICAN BLACK (Haematopus moquini) The oystercatcher's origins can be traced on the evolutionary scale to approximately 60-80 million years ago. They originated in the Southern Hemisphere and today they exist mostly in the southern Hemisphere with 10 species in existence. Avocets and stilts are the oystercatcher's closest relatives. Various species of oystercatcher are found in New Zealand; South America and North America. In South Africa one species of oystercatcher exists. Food options are limited because they live on a narrow tract of land. They specifically choose limpets as well as mussels. Limpets are nocturnal and move around a lot ...this is when the oystercatcher does most of its feeding. The oystercatcher is equipped with a dextrous and very strong beak. The oystercatcher is territorial and will defend its territory from other . They are faithful to their mates and can live 20-40 years. Nests are not very obvious and often found in open ground. The eggs are well camouflaged and approximately 2 eggs are laid. The eggs take a month to incubate and are laid between October and November. Chicks are covered in down and eyes open when they hatch but it is unable to feed itself and parents bring food to the chicks often leaving a midden of empty shells near the nest. It takes 40-50 days before the chick is fully fledged and at that stage is still unable to open its own shells. The parent only rears 1 brood of chicks per year and they do not breed in winter. It has been discovered that some young juveniles spend time in Walvis Bay. 200 have been counted there. Oystercatchers do not breed until they are between 6 and 12 years old. At present, it is estimated that approx 5000 oystercatchers exist throughout the world. Problems in conservation results from the oystercatcher breeding in the height of summer when there is more likelihood of their nests and chicks being destroyed in the sand and dunes by predators and man. Oystercatchers are devoted parents but chicks are subject to predation/human disturbance. There is also the possibility of having infertile eggs in the nest. The only documented case of an oystercatcher chick being abandoned was due to the habitat/beach being destroyed by a film set at Scarborough. The young oystercatcher looks different from the adult in that it has pale legs, the beak has a dusky brown tip to it and the eye ring is not as bright orange as the adult. Another problem in oystercatcher conservation is that the birds are very long-lived; they are territorial and they do not reproduce in sufficient numbers. In theory they need to rear 1 chick every 3 years. Natural predators include genets and the Cape foxes. In , the jackals are a threat. Dangers to the oystercatcher include red tides that lead to starvation. Avian cholera affected the oystercatcher population in the 1990's. transport this disease. Conservation

The Oystercatcher Conservation Programme, launched in 1998, undertakes research on the African black oystercatcher and aims to develop a conservation strategy for the African black oystercatcher. In addition, this bird is listed on Appendix II of the African-Eurasian Waterbird Agreement, which calls on parties to the agreement to engage in a wide range of conservation actions.

OTHER BIRDS IN THE RIVER MEANDER

CAPE CANARIES (Serinus canicollis) The Cape Canary is a small bird in the . It is a resident breeder in eastern and southern Africa. Its habitat is fynbos grassland and gardens, preferably in highland areas. It builds a compact cup nest in a scrub. The Cape Canary is 11–13 cm in length. The adult male has a green back with black edging to the wing feathers wings and tail. The underparts, rump and tail sides are yellow, and the lower belly is white. The rear head and neck are grey, and the face is cinnamon. The female is similar, but with a less grey on the head. The juvenile has greenish-yellow underparts with heavy brown streaking. This species is easily distinguished from the Yellow-Fronted Canary by its lack of black face markings. The Cape Canary is a common and gregarious seedeater. Its call is tsit-it-it, and the song is warbled Goldfinch-like trills and whistles given in display flight or from a high perch.

CAPE (Motacilla capensis) The is a small bird in the same family which includes the , and . This species breeds in much of Africa. This is an insectivorous bird of open country, often near habitation and water. It prefers bare areas or short grass for feeding, where it can see and pursue its prey. In urban areas it has adapted to foraging in gardens or paved areas such as car parks. Pairs make bulky nests in crevices in natural and man-made structures, and lay up to seven eggs. The Cape Wagtail is a slender bird, 19–20 cm in length, with the characteristic longish, constantly wagging tail of its . The adult is plain grey-brown above, apart from pale wing edges and a short white supercilium. It has off-white underparts, with a dark grey band across the breast. Young birds are duller and have yellowish underparts. Cape Wagtail has a tsee chee chee call and a trilled whistled song. This wagtail forages energetically for insects on the ground, alone or in pairs, moving with a characteristic bobbing motion that causes the tail to swing up and down. Feeding is often near water, including garden ponds, and this bird will eat tadpoles or tiny fish if the opportunity arises.

MOORHENS (Gallinula chloropus) The Common Moorhen is of the family with an almost worldwide distribution. It is often called the "Common Waterhen", especially in the British Isles, and this is a more descriptive name because the bird lives around well-vegetated marshes, ponds, canals, etc., and is usually not found in moorland. Another name, popular in the USA, is Common Gallinule. The bird is not found in the polar regions, or many tropical rainforests. But elsewhere the Common Moorhen is likely the most commonly seen Rail species to most people. This species will consume a wide variety of vegetable material and small aquatic creatures. They forage beside or in the water, sometimes upending in the water to feed. It is often secretive, but can become tame in some areas. Despite loss of habitat in parts of its range, the Common Moorhen remains plentiful and widespread. On a global scale – all taken together –, the Common Moorhen is as abundant as its vernacular name implies. It is therefore considered a Species of Least Concern by the IUCN.

CAPE BULBULS (Pycnonotus capensis) The Cape Bulbul is a member of the bulbul family of birds. It is an endemic resident breeder in coastal bush, open forest, gardens and fynbos in southern South Africa. This species nests mainly in the southern spring from September to November. The nest is thick walled cup concealed by foliage in a small tree or shrub. This species is much darker than the other South African bulbuls. The Cape Bulbul is a common and conspicuous bird, which tends to perch at the top of a bush. It is active and noisy, usually seen in pairs or small groups foraging for fruit, nectar and insects.

GANNETS, CORMORANTS AND

Gannets, cormorants and pelicans are closely related to , frigate birds and tropic birds. Members of the last two groups occasionally visit southern African waters, but they do not breed in the region, and darters are found only in inland waters. Southern Africa has one species of breeding , five of breeding cormorants and two of breeding pelicans. Together with the , one of the cormorants (the Reed ) and one of the pelicans (the Pink-backed ) are restricted to inland waters; a second cormorant (the White- breasted Cormorant) and the other pelican (the White Pelican) occur in both marine and inland waters.

The and the Cape, bank and crowned cormorants are restricted to the marine environment. These species breed only in southern Africa and may therefore be regarded as endemic to the region, although their migrations, when not breeding, sometimes take them beyond the subcontinent. For instance, juvenile Cape gannets were regularly recorded moving well up the West African coast in the 1950s. They ranged as far north as the former Spanish Sahara in those years. Along the eastern coast of Africa the Cape gannet may reach the mouth of the Limpopo River. Vagrants have been recorded as far a field as Australasia, and similarly a few Australasian gannets have been seen at South African gannetries. Feeding methods Gannets plunge from the air onto fish prey near the surface of the water and search for large shoals of fish, such as those formed by pilchard. However, off central Namibia, for example, pilchard have been replaced in the food chain by the smaller bearded gobies, fish which do not congregate in such dense shoals as pilchard and which also live deeper in the water. Although other have been able to adapt to feeding on the gobies, gannets have not done so to any great extent.

Guano Historically the Cape gannet and the were of great importance as the main producers of guano, a manure much sought-after for agriculture. However, the advent of artificial fertilizers and a fall in guano harvests brought about a decrease in the value of this industry, although it nevertheless survives to the present day. For seabirds to produce commercially exploitable quantities of guano, they have to be abundant. If there are a sufficient number of birds, enough guano is deposited to make its collection worthwhile. The often nests under boulders or bushes where guano is difficult to collect, or in burrows in sandy soil, where the guano is soon mixed with sand and is therefore of poor quality. Cape gannets construct their nests from guano and mud, but once the guano has been scraped from their breeding areas there is often not much material left for nest building. Moving in sand from penguin breeding areas therefore provides gannets with guano-rich material for nest construction. Guano scraping has had disadvantages for birds. It has led to the areas where birds breed being lower than surrounding terrain, and heavy rain can then cause periodic flooding, killing both eggs and chicks. In 1985, Malgas Island became part of the and guano has not been scraped. Therefore, the breeding season is longer than when guano was scraped. The guano industry has undoubtedly also had some benefits for sea-birds. The construction of guano plat- forms north of Walvis Bay provided alternative safe breeding places at a time when the islands in nearby estuaries had become or were becoming joined to the mainland, thereby allowing access to them by predators. At some islands the area available for birds to breed has been increased by construction of wooden platforms overhanging the sea, or by the building of large walls to keep out heavy seas. Guano yields at southern African islands decreased substantially in the 1960s and 1970s, perhaps partly because artificial fertilizers were becoming widely available, but mainly because the collapse of pilchard resources off South Africa and Namibia led to less food being available for guano-producing birds. AND Two other families of seabirds breed in southern Africa - the gulls and the terns. As do some cormorants and pelicans, a few gulls and terns also breed inland. Those breeding around the coast are Kelp , Hartlaub’s gull, greyheaded gull, roseate , , swift tern and . Of these, the Hartlaub's gull and Damara tern breed only in southern Africa. The and swift tern have wider distributions, but the particular forms found in southern Africa are found nowhere else. Therefore, of southern Africa's 14 breeding seabirds, nine may be regarded as endemic. This high proportion results from the isolation of suitable coastal breeding sites off southern Africa, referred to earlier. Most of southern Africa's seabirds breed in colonies. The Damara Tern is the least colonial of all, and the only one of the 14 that breeds entirely on the mainland. It is a small tern with a total population of 1 000 - 2 000 pairs, the majority of which breed in summer in Namibia, north of Swakopmund. Blackbacked jackal and other predators prowl that region, and it is to the birds' advantage for their colonies to be inconspicuous. Therefore, the nests are well dispersed. The southern African population of swift terns numbers about 5 000 breeding pairs. Many nest in mixed colonies with Hartlaub's gulls, of which there are about 13000 pairs. Off western South Africa, the swift tern feeds mainly on , which it picks from surface waters. As shown on this page, the number attempting to breed in different years may vary considerably, probably because of variations in the quantity of food available. The greatly reduced breeding off western South Africa in the autumns of 1990 and 1991 was at a time when anchovy was scarce. All three species of gull are opportunists and can often be seen scavenging from man's wasteful activities, for instance at rubbish dumps or behind fishing trawlers. All three have also found new safe places to breed or roost - on the tops of tall buildings, sewage-works and salt-works, and guano platforms. It is the result of such adaptability that some species of gull elsewhere have been able to increase numbers. SEABIRD BREEDING STRATEGIES Seabirds of southern Africa employ variety of breeding strategies. Some lay their eggs in spring, others in autumn and still others virtually throughout most of the year. Eggs produced in spring will normally have hatched by summer, when day length is longest. Because most seabirds hunt in daylight, there is more time in summer for parents to obtain food for their chicks. The Hartlaub's gull is more nocturnal than the other species. For example, after dark it has been known to catch insects attracted to streetlights near Cape Town's docks. Many of the fish preyed on by seabirds are only seasonally available in certain areas, and this fact too is an important consideration in selecting a time to breed. Bank cormorants often nest in the most precarious places, and their entire nest can be washed away by heavy seas. For species subject to such hazards, it is obviously important to be able to lay another clutch of eggs should the necessity arise, and the breeding season is then often prolonged. Of course, with an extended breeding season it is possible for parents to raise more than one brood of chicks in a year. Clutch size also varies. Cape gannets and swift terns generally lay a single egg, African penguins normally two, and cormorants and kelp gulls often three eggs or even as many as five. Obviously, the larger the clutch, the greater the number of mouths to feed, but the faster the potential of the population to increase. With a single chick, it is easier for the parents to ensure that it is adequately fed. Rarely do gannet chicks starve, but Cape cormorants have frequently deserted their nests if food is scarce nearby. When the nests have eggs or small chicks, one parent has to remain at the nest to incubate the egg, to shelter the young chicks from intense heat or cold, or to guard both from attack by kelp gulls, which frequently make a meal of an unprotected egg or chick. Therefore, if one parent is absent too long, the attendant parent is forced to leave to feed itself.

Colonial Breeding and why it protects the species We already know that some species are more colonial than others. Cape gannets breed in massive colonies, whereas nests of Damara terns are often so well separated that they are difficult to locate. A number of reasons for colonial breeding have been postulated. One is that it has been forced upon seabirds by the lack of suitable nesting space at islands. Certainly this is true at islands such as Mercury, which in recent years has been decolonised by South African fur seals. The seals displaced many birds from areas where they formerly bred, including about 15% of the world's population of bank cormorants, many African penguins and many Cape cormorants. However, at some large islands there is plenty of breeding space and seabirds still breed in colonies Possession and Dassen islands are examples. Another possible advantage of colonial breeding is that the risk of eggs or chicks being taken by predators is reduced. Birds nesting close to each other tend to provide group protection against such natural predators. Nests near the centre of the colony may be especially safe, and experienced birds often take these sites A third possible advantage of colonial breeding is the gaining of information about the location of good feeding areas. A nesting swift tern may, for example, observe that birds returning from a particular direction are all carrying fish whereas those flying in from another direction are doing so empty-billed. Another reason could be that the birds huddled together can keep each other warm. This is unlikely to apply to southern Africa, though for one species of penguin breeding in Antarctica, it could be an advantage. Perhaps, however, it is just that colonies form simply because they are good places to breed and unlikely, for example, to be flooded. MIGRANT SEABIRDS Large numbers of seabirds that breed elsewhere visit the region each year. They come from inland, from the tropics, and from the cold portions of both the northern and southern hemispheres. To date 78 species of migrant seabirds from 12 families have been recorded in southern African waters, and two others may occur at sea. Three penguin species occasionally visit southern Africa. Travelling from Sub-Antarctic or Antarctic islands. Their scarcity can be attributed to their having to swim the entire distance, whereas other birds can fly. Other birds that have been recorded include the blacknecked . Nine species of , petrels, Antarctic fulmar, prions, shearwaters and the Pintado with its spectacularly coloured plumage. The whitechinned petrel and the abundant are particularly common. Five species of storm petrel visit southern Africa. Migrant seabirds visit southern Africa for a number of reasons. Some of the rarer ones probably arrive unintentionally - perhaps being swept off course by strong winds or currents. Other species merely pass through on their way between breeding and non-breeding areas, examples being the blackbellied storm petrel and the . The former breeds in the Southern Ocean and winters in the tropical Atlantic, Indian and Pacific oceans. Around southern Africa there is a plentiful supply of food and many of the migrant birds visit the region during their non-breeding season to feed. They employ a variety of techniques to catch prey. Some locate it from the air and plunge onto it - , terns and tropic birds are examples. Others, such as , . petrels and gulls, may seize prey while sitting on the surface. Smaller birds, for example storm petrels, prions and terns, often snatch prey from the surface while running along it or flying. Penguins, and some shearwaters chase prey underwater, attaining rapid speeds. The various species are not necessarily restricted to one method of feeding. For example, albatrosses, petrels and some storm petrels can also dive beneath the surface. Many birds benefit from man's fishing activities, which are by nature wasteful. Fish spill from purse-seine nets or escape from bottom or mid water trawls from the trawl fisheries. Also, unwanted fish may be discarded together with unwanted portions of sought-after fish such as hake heads and viscera. Such discarding provides a ready supply of food at the surface of the ocean for birds able to take advantage of it. Blackbrowed and shy albatrosses are abundant at trawlers, as are white-chinned and pintado petrels, but other albatrosses and petrels, skuas, shear-waters. storm petrels, prions. terns and gulls may also feed at trawlers. Two seabirds which breed locally - Cape gannets and kelp gulls, often join the flocks of birds feeding behind trawlers. In sealing operations, it is often only the pelt of the that is sought and the rest of the carcass is sometimes thrown into the sea. Northern and southern giant petrels use their powerful bills to feed on seal carcasses and they also used to gather at whaling stations at Langebaan and Durban Bluff when South Africa caught whales. Skuas and frigate birds obtain their food by chasing other birds and forcing them to regurgitate, a practice termed klepto- (kleptes = thief). Terns are often victims of such a practice although larger birds such as gannets may also be harassed. REFERENCES Attwood, C. September: 2000. Coast Care Fact Sheet. Estuaries and Lagoons series 1A Branch, M. Fact Sheet Birds 1 - Jackass Penguins. Branch, M. July 1996. Fact Sheet Mammals 1 – Cape Fur Seal. Hockey, P. The Black oystercatcher - Notes from a lecture on Riverine Ecosystem : Juta Major, N. May 2000. Rockhopper Penguins Fact Sheet. Matthews, S. September: 2000. Coast Care Fact Sheet Dune Vegetation series 1A Pamphlet : Environmental Focus 3, Rivers as Ecosystems. Payne A.I.L. & Crawford R.J.M. Secrets of the Seas - Illustrated guide to marine life off Southern Africa Professor Peter Barham is a Professorial Teaching Fellow in Physics at the University of Bristol, UK and visiting Professor of Molecular Gastronomy at the Royal Veterinary University in Copenhagen, Denmark. He is involved in African Blackfooted Penguin research in South Africa