Cuckoo-roller
Leptosomus discolor
A large, big-headed, short-legged bird that is very odd in almost every way, especially in the position of the eye near the top of the head. Males have a pale head and underparts and a colorful iridescent back. Females are rufous brown with heavy spotting below. Found in all forest types, and sometimes in adjacent scrub and plantations. Often perches and feeds in the canopy, though rarely on an emergent branch. Males and pairs frequently make soaring display flights, constantly giving incredibly loud and persistent three-part wailing calls. Much larger than Broad-billed Roller, with a dark bill. Looks raptor-like, but has a huge head, small bill, and less powerful wingbeats.
Identification
The cuckoo-roller has a total length of 40–50 cm (16–20 in); the nominate subspecies is the largest, and L. d. gracilis the smallest. Unlike the true rollers and ground rollers, where the sexes have identical appearance, the cuckoo-roller is sexually dichromatic. Males have a mostly velvety grey chest and head, changing gradually to white on the remaining underparts (the demarcation between grey and white is stronger in L. d. gracilis). The back, tail, and wing-coverts are dark iridescent green with a purplish tinge (especially on the wing-coverts), and the crown and eye-stripe are black. Females are mostly brown, with strongly dark-spotted pale underparts (less spotting in L. d. gracilis). Juveniles are generally reported as resembling a dull female, but at least juveniles of L. d. gracilis are sexually dimorphic, and this also possibly applies to the other subspecies. The bill is stout and the eyes are set far back in the face. The legs and feet are small, and the feet have an unusual structure which has confused many ornithologists, but is now thought to be zygodactylous (two toes forwards, two toes backwards).
Taxonomy
- Scientific name
- Leptosomus discolor
- Authority
- (Hermann, 1783)
- Order
- Leptosomiformes
- Family
- Leptosomidae
- Genus
- Leptosomus
Range and habitat
The cuckoo-roller occupies a wide variety of habitats, including altered areas. They inhabit forest, including rainforest, litoral forest, deciduous forest, spiny bush-forest, and tree plantations. In the Comoros, the species is found on all the major islands, particularly in forested zones. It can be found from near sea level up to 2000 m.
- Migration
- Resident species
Behavior
The diet of the cuckoo-roller is not well known, but a 1931 expedition found that chameleons and insects, particularly locusts and caterpillars, are important food items. Stomachs have often been found to be lined with caterpillar hairs, and other prey taken include grasshoppers, cicadas, stick insects, and geckos. The principal foraging technique is to perch motionless, watching for prey, then to make a quick sally towards the prey when observed. They also hunt from the air. Prey is caught in the large bill and killed by beating it against a branch.<p>Very few studies have investigated the breeding habits of the cuckoo-roller. It has been described in the past as a polygamous breeder, but no evidence for this is available. The nest is located in tall trees, 4–6 m (13–20 ft) off the ground, in natural cavities. No lining is placed inside the cavity; the white eggs are laid directly on the bottom. The usual clutch size is around four eggs. Incubation is performed by the female only, while the male feeds her. The incubation period is about 20 days, after which fluffy chicks are born. Chicks remain in the nest for 30 days before fledging.
Conservation
The species is not generally hunted and has proven resistant to habitat change that has threatened other native birds. It is assessed as Least Concern by the IUCN. The distribution of the cuckoo-roller is vast, and populations in Madagascar persist in small forest fragments. Areas with abundant populations include broad expanses of forest associated with reserves such as Zahamena, Andringitra, Andohahela, and Marojejy.
- Population trend
- declining
Photos
Distribution
Bird Calls
Other Birds
Lizard Buzzard
Kaupifalco monogrammicus
A small, chunky, grayish hawk with a distinctive pale throat spliced by a vertical black throat stripe; has one or two (rarely) broad white bars across the black tail. Occurs in singles or pairs in savanna and is often seen perched in the open, watching for insects, lizards, snakes, and other small vertebrates. Calls a loud shrill “peeee-eeeuuu” or repeated “whuuua-whuuua-whuuaa”. It is shorter-legged and has a more powerful build than most sparrowhawks. Most similar to Gabar Goshawk, both having a broad white rump band in flight, but Lizard Buzzard is distinguished by its distinctive throat pattern, pale tail bands, and pale tail tips.
Mongolian Accentor
Prunella koslowi
A very plain accentor of dry, open areas with sparse, scrubby vegetation. Patterning more closely resembles that of a lark or a pipit than another accentor: pale sandy brown all over with a paler belly and a finely streaked back. For an accentor, oddly shy and skulking, usually sticking to cover and infrequently vocalizing.
White-winged Collared-Dove
Streptopelia reichenowi
A distinctive dove with a restricted range. The white wing patches are usually visible when perched, and become very conspicuous in flight. A white eye-ring is conspicuous at close range. Found locally in riverside scrub, thickets, and adjacent habitats. Similar overall to Ring-necked Dove, but separated by the white eye-ring, gray breast, and white wing patches. The song is a fast-paced, quickly repeated rolling series of cooing notes with a somewhat rough, churring quality.
Start Your Bird Watching Journey
Identify a bird outdoors and keep the field guide close for your next observation.