Congo Serpent-Eagle (Dryotriorchis spectabilis) in the Cameroon lowlands

SchlangenbussardDriving from Edea down to Kribi in April 2017 we managed to catch a bird, unobtrusively crouching on a branch of a medium-sized tree right along the road. The bird had large eyes, but was sitting right in the open. Wow, this was the Congo Serpent-Eagle (Dryotriorchis spectabilis) is a medium-sized eagle that occurs in densely forested areas throughout western and central Africa. Normally prey is spotted in dark forest, either on a tree trunk, in foliage, or on the ground. But they also hunt along roads and forest clearings and may perch over rivers.

The Congo Serpent-Eagle is part in the family Accipitridae, and is classified in the monotypic genera Dryotriorchis. This species is found in West and Central Africa, with its range stretching from Sierra Leone south to Angola and west to the Democratic Republic of Congo. The Congo Serpent-Eagle (Dryotriorchis spectabilis spectabilis) is found in upper Guinean forests of Western Africa, while Congo Serpent-Eagle (Dryotriorchis spectabilis batesi) is found in lower Guinean forests in the south of Cameroon and Gabon.

Although monotypic, it seems to be closely related to Circaetus- Snake-Eagles like the Short-toed Snake-Eagle (Circaetus gallicus) and is possibly a link between these and the Asian genera Spilornis – Serpent-Eagles like the Crested Serpent-Eagle (Spilornis cheela). This hawk is a medium-sized bird with distinct short, rounded wings and a long, rounded tail. It is varying shades of brown on its back and has a slight crest. His chest is white, with varying amounts of a reddish rinse, and in the named subspecies, it is covered with round, dark spots. The subspecies Dryotriorchis spectabilis batesi only have these points on its flanks.

The Congo Serpent-Eagle resembles Cassin’s Hawk-Eagle (Spizaetus africanus). Thus the bird is superficially similar in plumage and size as Cassin Hawk-Eagle. It has been suggested that the Congo Serpent-Eagle evolved to mimic the Cassin Hawk-Eagle, which could give this slender raptor a comparable advantage as is said to other less-powerful raptors like e.g. European Honey-buzzard (Pernis apivorus). Possibly advantages include the ability to deceive its reptilian prey in not escaping, their own predation, and / or minimize mobbing by birds through its resemblance to a bigger bird predator. Dryotriorchis spectabilis spectabilis most resembles the immature Cassin Hawk-Eagle, while Dryotriorchis spectabilis batesi resembles the adult. This is one of the very interesting examples of avian mimicry.

It is a very vocal bird of prey, and is often one of the most heard species in its habitat – albeit seldom seen. It has a cat-like meow as the sound as well as a low, sad, nasal “cow cow cow” at intervals for long periods of time. When heard from a great distance, some ornithologists have compared their appeal to that of a Turaco.

The Congo Serpent-Eagle feeds on snakes, chameleons and toads, and hunts these species, dropping on them from a perch in the underbrush. Occasionally it perches on lower branches in tall trees. It hunts, dropping on the forest floor in the understorey, where it can attack its prey several times with its feet. This eagle can also grab the prey from foliage while hunting. His excellent vision allows him to hunt in the dark forest. Its large eyes allow this species to hunt in low light, although it is more a diurnal than a crepuscular bird. Studies on the eyes of the species have shown that they have about twice the visual resolution of a human being. The Congo Serpent-Eagle lives mainly in dense primary forest below 900 meters; the main hunting ground is the dark understory. As it is adapted for dense forest, it is not well suited for secondary forests and plantations. The Congo-Brazzaville obviously does not migrate, although it is not known whether it is locally nomadic. Very little is known about their breeding habits, although it is suspected to breed from June to December. The Congo Serpent-Eagle is listed as a species of Little Concern due to its wide variety and population.

Bird-lens.com decided for the Africa specialist Rockjumper. Cameroon is a vast and diverse land; lying just north of the equator. This bird-rich nation forms the inter-grade between West and Central Africa and harbors a wide range of habitats, ranging from steamy lowland rainforest to Sahelian semi-desert.

By combining the Rainforest & Rockfowl tour with the Northern Extension tour of the Africa-specialist Rockjumper I was confident to book a birding tour that visits all of the area’s core ecological zones and challenges the best birds of Africa – like the Congo Serpent-Eagle or the Grey-necked Picathartes in Campo-Ma’an.

In order to satisfy the growing demand for top shots of the rarer species of Palearctic, Bird-lens.com has undertaken targeted trips to distant bird areas and destinations nearby. This is to be able to do anything to provide excellent images of the birds of the Western Palearctic. Additionally bird-lens.com is keen to provide images of other birds of other parts of the world – especially if these birds are rarely photographed. The results in images of rare birds are very good. Very nice images bird-lens.com could be brought back from all over the world.

The beautiful image of the blog is only first impressions of what you will find in behind “Picture  Shop” for the Cameroon trip very soon. Simply contact bird-lens.com if you need an image of a bird before even more new pictures are online.

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