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Reason for the Stresemann’s Bushcrow Restricted Area

Despite the fact that Africa has an extensive region covered with savanna flatlands, the preferred habitat for the Stresemann’s bushcrow, this crow continues to confine itself to Southern Ethiopia, much to the bafflement of scientists.

There has been quite some speculation as to why this bluish-grey bird, also referred to as the Ethiopian bush crow, is only endemic to an area of about 24,000 km2 that surround the towns of Arero, Mega and Yabelo in Southern Ethiopia. Much of the habitat here, consisting of short grass and scattered acacia can also be found in plenty outside these pockets.

Stresemann's Bushcrow

A study published by BirdLife’s Dr. Paul Donald and Dr. Nigel Collar in the Journal of Ornithology sought to explain this oddity. It found that that this confinement could be down to the climate. The edge of Stresemann's bushcrow’s habitat is the same as that of a unique local climate, a bubble that is cool and dry. Temperatures inside the bubble are less than 200C while it is above 200C outside the bubble. Reasons why the bird is restricted to this specific temperature are yet to be found.

This odd phenomenon was discovered in the 1930s. This led to the bird being studied and researched intensely in a bid to get answers. For starters, this bushcrow has over time been placed in several bird families like the starling family Sturnidae and the monotypic family Zavattariornithidae. This is due to similarities it has with members of those families. The closest relatives to the Stresemann’s bushcrow include the magpies and the ground jays. Currently, it is widely considered to be a member of the crow family Corvidae although it has several features that are unlike members of that family like the fact that its bare facial skin is able to move and its palate structure is also distinct.

This bird species has been observed to forage for insects starting at sunrise alone and in pairs or groups. It digs out the soil vigorously with its slightly open beak. In other instances, you can find it picking apart rotten wood or cattle dung. Other insects are hunted on the backs of cattle. It is for these reasons that you can find the Stresemann's bushcrow following indigenous nomadic people of Ethiopia as they graze their cattle, all within its small habitat. Insects caught are carried to the nearest tree where they are pinned down and killed.

The climate restriction makes the Stresemann's bushcrow one of the most vulnerable to climate change. Changes in grazing habits of Ethiopia’s indigenous nomadic people in the area are also having a negative effect on the bird. It’s no wonder then that it is listed in IUCN Red List of Threatened Species as endangered. As of 2007, its number was estimated to have declined to less than 10,000 individuals.

To see this restricted bird species, a number of birding tours exist that offer a visit to its habitat as part of their itinerary. The region is open for birding enthusiasts all year round, the birds are, of course, non-migratory. We suggest you utilize the services of a guide, join a birding tour or be part of a birdwatching holiday group if you would like to observe the bird.