Endangered birds - Nature Travel Birding

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In 455 BC the Greek playwright Aeschylus could not shake the feeling that he was going to die. A prophecy had warned him of falling objects, so he was spending most of his time outside. Unfortunately, a large bird (now believed to have been a Bearded Vulture) mistook his smooth bald head for a rock and dropped a tortoise on it! Aeschylus died instantly, and it’s unclear if the vulture ever got his dinner.

The globally near-threatened Bearded Vulture is an unmistakable bird, with black ‘sideburns’ (or beard), red rings around the eyes (a feature only shared with some parrots) and a long wedge-shaped tail. It also has black wings, with the rest of the head, neck and body a rich rusty orange. This is because Bearded Vultures rub themselves with iron oxides. Soil and mud stained with iron oxide give the bird this fiery appearance. Theories to explain this feather staining range from dominance behaviour to parasite control. It could even be purely cosmetic, or might be for camouflage. They apply the dirt with their claws and then preen for about an hour to ensure a bright orange glow. They are also attracted to other red things, like leaves and red wood. Captive birds also partake in this behaviour, which suggests the activity is instinctual, not learned.

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The Bearded Vulture is sparsely distributed across a considerable range. It may be found in mountainous regions from Europe through much of Asia and Africa, including in the Alps, Pyrenees, Caucasus, Altai, Himalayas, Atlas and Ethiopian highlands. There is also an isolated population in the Drakensberg mountains of South Africa and Lesotho. It requires large open areas with little or low vegetation, and that is not continually covered with snow. It relies on thermals and wind for gliding flight, but to a much lesser extent than most other vultures. It has been observed gliding in the Himalayas at more than 8000m (26000ft) above sea level!

Unlike the myth, Bearded Vultures do not hunt live prey, and even avoid meat. Up to 90 % of the diet of the Bearded Vulture consists of bleached carcass bones, the only bird with this peculiar eating preference. The bird is capable of swallowing and digesting bones the size of a sheep’s vertebrae. If bones are too big, they are dropped onto rocks from a height of up to 100 meters, to shatter them. This unique eating habit makes Bearded Vultures an essential part of the ecosystem. Besides bones, they also eat small lizards, hares and tortoises, also dropping them onto rocks from a height. The acid concentration of the Bearded Vulture’s stomach has been estimated to be of pH about 1 and large bones will be digested in 24 hours, aided by slow mixing/churning of the stomach content. The high fat content of bone marrow makes the net energy value of bone almost as good as that of muscle, even if bone is less completely digested.

Bearded Vultures live in mountainous areas, often above the tree line. Because of the many animals that do not survive the winter, carcass supply is greatest in winter. Therefore, this is the time when Bearded Vultures breed, and chicks hatch in about two months. Bearded Vultures usually lay two eggs, but only the strongest one survives. After hatching the young spend about 4 months in the nest before fledging. The young may be dependent on the parents for up to 2 years, forcing the parents to nest in alternate years on a regular basis. Wild Bearded Vultures have a lifespan of about 20 years, but have been observed to live for up to at least 45 years in captivity.

Fewer than 10,000 pairs exist in the wild worldwide. Declines today are usually due to poisons left out for carnivores, habitat degradation, the disturbances of nests, reduced food supplies and collisions with power lines. They were formerly persecuted in significant numbers because people feared (obviously without justification) that it regularly carried off children and domestic animals!

For a chance to see this impressive and interesting bird, along with many others, join us on a Nature Travel Birding tour. We offer tailor-made private and small group birding tours across the globe, including to many countries that the Bearded Vulture can be found in. For more information, go to www.naturetravelbirding.com or get in touch by sending your query to info@naturetravelbirding.com

Here at Nature Travel Birding we love interesting birds. Whether it’s one that can mimic others in order to confuse predators, or one that has a dazzling courtship display, or one that can achieve incredible feats of endurance or strength, we love interesting birds. The Stresemann’s Bushcrow certainly fits in the category of interesting!
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Only discovered in 1938 and initially taxonomically moved from family to family, the species name was assigned in commemoration of the influential German ornithologist, Erwin Stresemann. It is also less commonly known as the Abyssinian Pie. As its name suggests, the species is assumed to be a member of the crow family Corvidae, but this has been widely debated in ornithological circles since the species’ first description.

Currently it sits in its own unique genus with genetic analysis revealing its evolutionary history to be more related to that of the Asian Ground Jays. It is an unmistakable pale grey crow-like medium-sized bird, with a striking black tail and black wings and bright azure-blue around the eyes.

Its evolutionary history is interesting in itself, but the explanation of its range restriction (the species is endemic to central-southern Ethiopia, in a very small area in Sidamo Province), with vast areas of seemingly suitable, unoccupied habitat existing directly adjacent to the species tight range, is nothing short of remarkable. Recent studies suggest that its current area of occupancy is delimited by a climate envelope that harbours a cooler, dryer and more seasonal climate than its surrounding area, but no one knows for sure. The bushcrows prefer flat, open-grass savanna with mature acacia and thornbush stands, with the greatest densities of birds where there are large stands of acacias close to grazing pasture or cultivated fields.

Adding to the complexity of the situation, the Stresemann’s Bushcrows appear unspecialised in their diet and rely heavily on traditional Borana pastoral rangeland for their survival. Their diet consists almost entirely of invertebrates, particularly insects, including larvae and pupae. They forage on the ground, strutting about alone, in pairs or in parties of five or six individuals. They sometimes dig vigorously in the soil, and have also been seen extricating prey from wood in the manner of woodpeckers. Increases in agricultural land, intensification of grazing regimes and a growing human population throughout its range have led to changes in land cover and subsequently to the degradation of the rangeland it depends on.

The Stresemann’s Bushcrow’s breeding usually starts in March, with the birds building their nest high in an acacia tree. The birds usually lay five to six cream eggs with lilac blotches. The nest itself is globular in shape with a tubular entrance on top. It is possible that more than just the breeding pair visit the nest and that the young of previous years help in rearing the new young.

There are currently thought to be only 9000 breeding pairs of these amazing birds left, and the species is currently listed as Endangered on the IUCN Red List of Threatened Species.

For a chance to see these interesting birds and many others, come join us on a Nature Travel Birding tour to the incredible African country of Ethiopia. Ethiopia is one of the most incredible birding destinations in Africa with over 860 species recorded which is about 9.5% of the world’s and 39% of Africa’s birds. For more information, visit www.naturetravelbirding.com or enquire directly at info@naturetravelbirding.com.