Download SASOL BIRDLIFE SOUTH AFRICA NATIONAL BIRD WEEK 30 April

SASOL BIRDLIFE SOUTH AFRICA NATIONAL BIRD WEEK
30 April - 6 May 2007
MARCH FOR THE PENGUINS
SEABIRDS AND SHOREBIRDS OF SOUTH AFRICA
Seabirds are associated with oceans and shores. Many species hardly even come inland to fresh water bodies
while some are found in oceans and inland water bodies. There are many different types of seabirds like
albatrosses, petrels, terns, gulls, cormorants, tropic birds, boobies, gannets, penguins, prions and
shearwaters. Many different species often share the same breeding grounds where their droppings form very
large deposits known as guano. Guano is very much sought after as a fertilizer but harvesting can often
destroy the fragile ecology of their breeding sites. Penguins’ eggs were harvested for eating in the old days
by fishermen and whale hunters. This had a devastating effect on penguin numbers and some populations
have never recovered from this impact.
Penguins are flightless birds with special adaptations that enable them to swim very fast to catch their prey.
Their bodies are like torpedoes and their wings developed into short, sturdy flippers while their feet are large
with strong webs that propel them through the sea. Some penguins live in very cold climates like Antarctica
while our African penguin (formerly the jackass penguin) lives in a much warmer climate along the
southern African coast. Its older name was derived from its donkey-like braying call. Penguins’ feathers
have been reduced through evolution to short stubble that is very oily that adds to their ability to glide
through the water. The oily feathers also help to keep their bodies warm in the cold waters of the oceans.
Penguins eat fish and other sea animals like crustaceans, squid and calamari. They breed on land like coastal
areas or islands deep in the ocean. Penguins are not scared of people and it is easy to get very close to them.
Albatrosses have very long wings that carry them for hours over the oceans without ever flapping their
wings. The wandering albatross has a wingspan of 3.2 meters making it the birds with the longest wings in
the world. Their long wings are narrow and designed like that of a glider plane that enables it to float and
glide effortlessly over the ocean. They only go to shores and islands to breed and make nests that look like
small volcanoes where they rear their chicks. Albatrosses are very good hunters and dive into water to take
fish. They also scavenge on carcasses of whales and seals that die in the oceans.
Petrels are real hunters and often predate on the nestlings of other seabirds like cormorants and gannets. The
giant-petrels like the southern giant petrel and the northern giant petrel are also called the vultures of the
oceans because they scavenge a lot on carcasses of other marine animals. Petrels, prions and shearwaters are
commonly known as tubenoses because they have an elongated bony structure on the upper mandible that is
an extension of the nasal cavities. Seabirds drink seawater and the petrels, prions and shearwaters rid their
bodies of the salt by producing a thick, salty excretion through their tube nose.
Cormorants live on the shores of oceans and some species also occur at freshwater bodies. They are
excellent fishers and catch their prey by swimming underwater. Cormorants spend much of their days
sunbathing to dry their feathers. In doing so, they become very hot and then cool themselves by ventilating
with open beaks and vibrating their throat pouches. They live in colonies on rocky beaches producing quite a
pungent odour from all their droppings. The Cape cormorant is a fairly common bird around the Western
Cape shores but the bank cormorant is much less common and an endemic species in South Africa.
Gannets are very beautiful birds with faces that appear to have perpetual smiles. Their wings are adapted for
fast and powerful flight and their bodies are made for diving deep into water. Once they locate fish they fold
their wings and dive like torpedoes into the ocean to take fish as deep as several meters under the water.
Gannets like many other seabirds live in very large colonies of tens of thousands of birds. Our own Cape
gannet has suffered from predation a disturbance by Cape fur seals and also white pelicans. Plummeting
marine fish stocks, absence of mammalian predators to keep seal numbers in check and human disturbance
all add to the reasons why seals and pelicans aim their predation at Cape gannets. There is another group of
seabirds called the boobies that are closely related to gannets but they are seldom seen in South Africa.
Gulls and terns are very common on the seashores and are represented by a large number of species. Some
gulls and terns are found inland at freshwater bodies while others like the southern black-backed gull and
Sabine’s gull are strictly found on the seashore. Gulls scavenge a lot and use the scraps left behind by
fishermen as a food source. Terns are much more slender than gulls and fly with grace. They have slender
beaks that they use for fishing very much like gannets. Some terns like the swift tern are large birds while
the endangered roseate tern is much smaller. Gulls also fish but prefer to swim in the water and take fish
from there.
There are other seabirds like red-tailed tropic bird and the greater frigate bird that hardly ever come to
our shores. Tropic birds have beautiful long tails while the frigate birds have heavy bodies with long tails.
These birds are found on our South African shores after tropical storms or cyclones as the strong winds carry
them from the seas to the continents.
Shorebirds include many of the small waders like sandplovers, plovers, sandpipers, knots, godwits, stints,
phalaropes, yellow-legs, greenshanks, redshanks, turnstones, oystercatchers and many others. Whereas
seabirds have webbed feet for swimming the shorebirds have normal feet for walking. Some of them like the
stints, plovers and sandpipers run very fast on the sandy shores. Their beaks are adapted for their particular
food and feeding behaviour. They mostly feed on small insects, sand-locked crustaceans, worms and
shellfish.
The African oystercatcher is endemic to southern Africa and feeds on clams and other shellfish on rock
shores. Their nests are shallow scrapes in the sand where the eggs are jealously guarded by the parents. The
banning of beach driving resulted in an increase in oystercatcher numbers because 4X4 vehicle don’t destroy
their nests any longer.
Little stints, ruff and the various sandpipers like the common sandpiper and marsh sandpiper are
abundant on the seashores but these birds are also at ease around freshwater bodies. They have longish beaks
that are used to probe the sand and mud flats for invertebrates that form the bulk of their food. Insects that
frequent the shore environment also form part of their diet. Their legs are relatively long to their body size to
allow them to wade in shallow water. It also offers them an opportunity to predate o small sea organisms
that are washed ashore in the wave action. Many of these birds are migrants that fly very far from the
northernmost parts of Europe to visit South African in the southern summers.
Birds like the bar-tailed godwit, spotted redshank, Eurasian curlew and common greenshank are also
waders with long beaks used for feeding in sand and mud. Some of them also come inland to freshwater.