BIRD OF THE MONTH; by Doreen McColaugh

Little Grebe

Se.nwedi

Bird of the Month: by Doreen McColaugh

There are 22 species of grebes in the world, of which three are resident in Botswana. These are the Great Crested Grebe at 50 cm, Black-necked Grebe at 28 cm and the Little Grebe at only 20 cm long. The Little Grebe, Tachybaptus ruficollis, is more commonly known as the Dabchick and is the most wide spread grebe in Botswana and the one you are most likely to see in freshwater dams, lakes, pans with water that can be saline and even at sewage ponds. When breeding they prefer water areas that are not too deep that cover vegetation below. Although they breed at any time of the year, a good time to see breeding birds is between August and March (depending on different areas of the country). After breeding they will move to areas with deeper water.

This small waterbird has a plump appearance with a rounded rump that looks tail-less, but it does have a little,  fluffy ‘powder puff' tail. It looks buff or a light brown coloured but is darker above, but with a rufous neck, cheeks and flanks. The rufous colour is brighter in the male when they are breeding. This, and its behaviour, form the basis for its scientific name from Greek and Latin. Takus, means ‘fast’ and bapto, is ‘to sink under’ while in ruficollis, rufus, means ‘red’ and collis, is ‘neck’ or ‘necked’. A true waterbird, the Dabchick is an excellent swimmer and diver and can dive repeatedly at depths for its aquatic food, staying under the water for up to 30 seconds each dive. The Dabchick’s legs are well towards the back of its body and this placement helps it swim and dive more easily. When it does go on land this placement of the legs, however, causes it to walk rather clumsily. Dabchicks have lobed feet but can swim as well as those waterbirds that have webbed feet. This bird’s size and activity make it fairly easy to identify, but the head is also a key to identity with the black bill that has a noticeable white spot at the base of the bill at the gape when in breeding plumage.The bill of juveniles is    yellow and their plumage is lighter in colour.

Dabchicks spend most of their life on and in water. They dive for their food which consists of small fish, frogs and a variety of aquatic insects and their larvae. They sometimes follow swimming ducks, depending on them to disturb things that they can catch and eat. They have even been recorded following hippos that also disturb aquatic insects and other edible food items.

Rainfall and flooding stimulates breeding which can occur at almost any time of the year. The Little Grebe does not breed colonially as do some other grebes. During breeding times they prefer shallower water with underwater vegetation. Both the male and the female together build their nest that is constructed of soggy underwater weeds and other vegetation that they bring to the surface to form the floating platform of the nest that is usually hidden in emergent vegetation and sometimes even attached to it. There is a shallow cup on the top of the floating nest where the 3 -5 eggs are laid. Incubation starts when the first egg is laid and both the male and the female incubate the eggs during the approximately 20 day incubation period. The pair also add vegetation to the nest during this time to keep it afloat and will also use some of the vegetation to cover the eggs anytime they are away from the nest. Upon hatching the chicks are very active and are said to be ‘nidifugous’ meaning they leave the nest very soon after they hatch. Since all of this takes place on water the chicks, although they can swim, also may be seen riding on the backs of adults during the first two weeks of their life. The parents care for them and help feed them for about two months until they can fully support themselves.   

  

Dabchicks have an unusual very dense, waterproof plumage. They can adjust this plumage to change their buoyancy, depending on the depths they are diving. This they do by varying the angle of their feathers and determining how close they press them against their body. Although Dabchicks can fly, they are reluctant to do so. When threatened or in real danger they quickly dive and then travel some distance before surfacing. Because they can dive so quickly and seem to disappear they have sometimes been referred to as a ‘hell-diver’ or a ’water witch’. They also can appear to be standing on water when they come to the surface and begin to strongly flap their wings which allows them to be upright on the water’s surface. Sometimes using the same motions they ‘run’ along on the surface instead of ‘standing’ and then sink back to the surface while giving their noisy, descending trill call.

Call it Little Grebe or Dabchick, this little waterbird of 100 -140 g competes well in its aquatic world. Should you be in its preferred breeding areas in summer after rains look for the Dabchick and observe some of its interesting behaviour.

References consulted:

Dennis, Nigel and Warwick Tarboton. 1993. Waterbirds: Birds of Southern Africa’s Wetlands. Struik Publishers, Cape Town.

Hancock, Peter and Ingrid Weiersbye. 2016. Birds of Botswana. Princeton University Press. Princeton, New Jersey.

Liversidge, Richard. 1991. The Birds Around Us. Fontein Publishing Company. Parklands, South Africa.

Newman, Kenneth in association with Irene Bredenkamp and Phoebus Perdikis. 2000. Newman’s Birds By Colour. Struik Publishers, Cape Town.

Tarboton, Warwick. 2001. Nests and Eggs of Southern African Birds. Struik Publishers, Cape Town.

Grebe Wikipedia https://en.wikipedia.org/wiki/Grebe (Accessed 4/11/2019)

Little_grebe Little Grebe Bird Facts the RSPB https://www.rspb.org.uk/birds-and-wildlife/wildlife- guides/bird-a-z/little-grebe/ (Accessed 4/5/2019)

Little grebe WIKIPEDIA https://en.wikipedia.org/wiki/Little_grebe (Accessed 4/5/2019)

Little Grebe The Wildlife Trusts https://www.wildlifetrusts.org/wildlife-explorer/birds/grebes-and-

divers/little-grebe (Accessed 4/5/2019)

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