'Bird parties' in the forests of St Lucia.

Green malkoha are often members of mixed species bird parties in St Lucia

Birding in the forests around St Lucia is usually characterised by long periods of relative quiet which are interrupted suddenly by periods of absolute chaos where birds of different species are calling and flitting seemingly everywhere and in all strata of the forest-from the forest floor to the canopy. These congregations or loose affiliations of birds are commonly referred to as ‘bird parties’. 

Typically, bird parties consist predominantly of insectivores but this is not a rule and often depends on the catalyst for the bird party. 

As an example, a fruiting fig tree may attract a variety of frugivorous birds such as White-eared barbet, Livingstone’s turaco, Trumpeter hornbill, African Green pigeon, Purple-crested turaco, Yellow-rumped tinkerbird  and Blackbellied starling. The fruits may also attract a variety of insects. As the frugivorous birds move through the trees feeding, they flush these insects making them more visible and easy to catch for insectivorous birds such as Green malkoha, Square-tailed drongo, Narina trogon and Olive bush-shrike. Whilst feeding the frugivorous birds also drop fruits to the ground. Decaying fruits attract detrivores which provide food for birds of the forest floor such as Terrestrial brownbul, Brown scrub-robin and Red-capped robin-chat. Fruit flies attracted to the decaying fruits also provide food for insectivores in the lower to mid-stratum such as Blue-mantled crested flycatcher, Woodward’s batis, Black-throated wattle-eye and Green-backed camaroptera.

The catalyst for bird parties may also differ. It could be an eruption of caterpillars, termite emergences or nectar-filled flowers.

Besides the food aspect, birds also benefit from bird parties in other ways. With plenty of birds around there is increased vigilance for avian predators such as African goshawk, Little sparrowhawk and Black sparrowhawk as well as for snakes. Participants in the bird party also have the ability to group together and mob predators when in groups whereas individually they are powerless. Lastly, there is also the benefit of ‘having more on the menu’ for predators. The predators have more options when hunting and therefore birds are safer on an individual level.

Some bird species may therefore join bird parties purely from a safety perspective even if it doesn’t benefit their feeding. This is often the case with seed eaters such as Grey waxbill, Green twinspot and Red-backed mannikin.

Bird parties do not however always start due to a rich food source. According to my observations around St Lucia, Terrestrial brownbul are the common denominator in most bird parties. They are gregarious and travel in noisy groups along the forest floor. Their Afrikaans name ‘boskrapper’ (bush scratcher) describes them best. They scratch very enthusiastically through leaf litter, tossing leaves to the side as they search for invertebrate prey. The disturbance they cause flushes insects for other insectivorous birds. As a result, a group of Terrestrial brownbul usually has a Green-backed camaroptera in tow as well as other lower to mid-stratum insectivores. In short, the bird party starts from the forest floor upwards in this example- the disturbance caused by birds in each strata of the forest benefitting those above.

Needless to say, these chaotic bird parties have most birders wishing they had independently moving eyes like chameleons, rotating heads like owls  and neck muscles that didn’t hurt so damn much from gazing upwards!

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