August 16, 2024 - Rufous-headed Ground-Roller (Atelornis crossleyi)
These ground-rollers are found in lowland and mountain rainforests in eastern Madagascar. Foraging on the ground and rarely flying, they feed on invertebrates such as ants, beetles, millipedes, and snails. Probably breeding from December to January, they excavate nest chambers at the ends of burrows in earth banks where females lay clutches of two eggs. They are classified as Near Threatened by the IUCN due to habitat loss and hunting.
Referred Species: B. langrandi (Ampoza Ground Roller), B. leptosomus (Short-Legged Ground Roller)
Status: Extinct - Extant, Vulnerable
Time and Place: Within the last 12,000 years, in the Holocene of the Quaternary, through today
These ground rollers live entirely on the island of Madagascar
Physical Description: The living Short-Legged Ground Roller is a round bird, with a decently sized tail and a distinctive puffy throat. These birds are fairly large, ranging from 30 to 38 centimeters in length. These are the largest rainforest ground-rollers, making them extremely unique in terms of dinosaur morphology and ecology correlation. They have sharp, dark beaks, and lightly colored legs - which are short and skinny. Their bellies and necks and rumps are white, but the necks and bellies and chests have brown speckling as well. The heads of the Short-Legged Ground Roller are chestnut brown, with white spotting and a white stripe above the eye. They have light brown and green backs, with green and brown wings. Their tails are fairly short, and light brown as well. Patterning is all over this bird, making it very distinctive to look at; the females are only slightly smaller than the males; and the juveniles differ by being duller in color. The Ampoza Ground Roller, presumably, looked similar, though little is known about its biology.
By Frank Vassen, CC BY 2.0
Diet: Short-Legged Ground Rollers - and most rollers - primarily feed on invertebrates, though they will also eat small lizards, snakes, frogs, and bird eggs.
Behavior: Ground rollers are usually more ground-laiden than the Short-Legged Ground Roller, which is the most arboreal member of this group - it spends a decent amount of time foraging in the canopy during the morning, before switching to more ground hunting during the afternoon and twilight. It will perch, completely motionless, for long periods of time, looking for prey. Then, it will strike extremely fast in order to catch its food. It will rfulle its feathers and flick its wings while pumping its tail in anticipation of the hunt. They usually grab prey from tree trunks and in foliage, though sometimes food is taken off the ground and in the leaf litter. They also will catch insects by grabbing them from their perches. They kill their food by hitting it against a branch and squeezing it with the tip of the bill, and then swallowing it whole. Presumably, the late Ampoza Ground Roller had similar feeding habits.
By Francesco Veronesi, CC BY-SA 2.0
The Short-Legged Ground Roller makes single, deep “boob” calls, sort of owl-like, that are repeated every 1 to 5 seconds for four minutes. Descending calls of “doodoodoo” often follow rapidly for a few seconds. They also make more churring calls during sunrise, accompanied by distinctive head-bobbing. They make kroo-kroo and other calls when finding each other, as well as purring and squawking during courtship. They are very secretive, however, and it’s difficult to catch these behaviors in the wild. It doesn’t migrate, but it is territorial, guarding over a large range for a mated pair.
By Frank Vassen, CC BY 2.0
Short-Legged Ground Rollers begin courtship and copulation in October, continuing through January; nests are built in December, which is also when eggs are laid. The nests are made in tree cavities or root masses, made of earth and foliage. The female lays one to two white eggs, which are incubated primarily by her; the male will bring his family food. The young hatch after about a month, and then leave the nest after another month.
Ecosystem: Short-Legged Ground Rollers live in humid rainforest habitat in lowland to middle altitudes, usually in the denses and darkest forests with very large trees. They are rarely found in open habitats with degraded trees. Their nests are vulnerable to parasitism and predation by bees.
By Mariusba, CC By-SA 3.0
Other: Short-Legged Ground Rollers, despite being considered fairly common, are vulnerable to extinction primarily due to rapid habitat loss and some hunting. Interestingly enough, habitat loss - a transition from rainforest to arid climate - is the reason for the Ampoza Ground Roller’s extinction, pointing to the Short-Legged Ground Rollers being extremely vulnerable to such a condition themselves.
Species Differences: The Ampoza Ground Roller is not only extinct, but found on the western side on the island; the Short-Legged Ground Roller is alive and mostly found on the eastern side.
~ By Meig Dickson
Sources under the Cut
Goodman, S. M. 2000. A description of a new species of Brachypteracias (Family Brachypteraciidae) from the Holocene of Madagascar. Ostrich 71:318-322
Hume, Julian P. (2017). Extinct Birds (2nd ed.). Bloomsbury Natural History.
Jobling, J. A. 2010. The Helm Dictionary of Scientific Bird Names. Christopher Helm Publishing, A&C Black Publishers Ltd, London.
Jobling, J. A. (2017). Brachypteracias in Key to Scientific Names in Ornithology. In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.) (2017). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.
Kirchman, Jeremy J.; Hackett, Shannon J.; Goodman, Steven M.; Bates, John M. (2001). "Phylogeny and Systematics of Ground Rollers (Brachypteraciidae) of Madagascar". The Auk. 118 (4): 849.
Langrand, O. & Kirwan, G.M. (2019). Short-legged Ground-roller (Brachypteracias leptosomus). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.
Thorstrom, Russell; Lind, Johan (3 April 2008). "First nest description, breeding, ranging and foraging behaviour of the Short-legged Ground-Roller Brachypteracias leptosomus in Madagascar". Ibis. 141 (4): 569–576.
Time and Place: Within the last 10,000 years, in the Holocene of the Quaternary
The Long-Tailed Ground-Roller is only known from a small portion of the Southwestern coast of Madagascar
Physical Description: The Long-Tailed Ground-Roller is a medium-sized bird, ranging between 34 and 47 centimeters in length. These are very visually distinctive birds, with long, pointy tails sticking up off of their buts. These tails are taupe and black striped, with the stripes being extensively distinctive in the males. These birds have speckled backs of light brown, black, and red; their wings are light brown with white tops and black under parts. They have red patches on their necks and throats, with black bands around these patches. Their heads are light brown, with black striping over them. They have long, skinny legs that are pale yellow; and thick, sharp, black beaks. Their bellies are white, with maybe some light grey spotting. It is very hard to miss this beautiful bird!
Diet: The Long-Tailed Ground-Roller mainly eats invertebrates, including ants, beetles, butterflies, caterpillars, cockroaches, grasshoppers, woodlice, and worms.
Behavior: The Long-Tailed Ground-Roller spends a good amount of time running about on the ground, rummaging through leave litter and dirt for its favorite food. It can also fly a little bit, catching food in mid-air, but it is very limited in flying abilities and rarely relies on them for gathering food. It is a very powerful runner, spending most of its time on the move in search of food. It is usually hunting at twilight and during the night, but it can also be found hunting during the day.
By Frank Vassen, CC BY 2.0
The Long-Tailed Ground-Roller is a fairly noisy bird, making a wide variety of calls, depending on the situation; while it does so, it’ll bob its head and raise its tail. When fighting for territory, males will make even, low-pitched “boo booo boo” calls, which can be heard over distances of 200 meters. These are made most frequently during the day, sometimes even a few meters off of the ground while perched in trees. All sexes make chuckling calls when they’re near their mate, usually lasting for half a minute and ending in a harsh, scratching note along with displays of the wingtips. While on the ground or in low branches, they also can be found making low “gu gu gu gu” calls, sometimes preceded by “too-tucs” in short concession. These calls are made by mated pairs calling to each other while hunting near the nest. If there’s a real and present danger to the nest, they’ll make a “too-tuc” call again, louder and more drawn out, along with scratching noises to get the attention of their mate.
Interestingly enough, the Long-Tailed Ground-Roller also raises its tail when excited. This is difficult to see, however, as it is a very shy bird.
By Gerry Zambonini, CC BY-SA 2.0
These birds start breeding in October and continue through January, though they peak in November and December when the rainy season is at its peak. A monogamous bird, the pairs are very territorial, and defend their nests vigorously. They build nests together near open areas, with the male feeding the female throughout the process. They use their bill sand feet to dig a ditch in the sand, far from vegetation; usually this burrow is about 8 centimeters in diameter. They line it with dry vegetation, and can make up to six nests in a season, but usually only one is tended to. These birds will display to each other while they construct the nest, using bill tilts, loud cracks, and flapping wings, to impress each other. They lay two to four white eggs, and the young are fed by both parents. They’re usually cared for for a while after fledging, living together in family groups. These birds don’t migrate, though they can move seasonally from one area to the next based on water availability.
By Quartl, CC BY-SA 3.0
Ecosystem: The Long-Tailed Ground-Roller is endemic to Madagascar, living in a narrow strip of habitat by the coast. This habitat is mainly arid thorn-scrub and deciduous woodland, dominated by weird Madagascar foliage. It stays where shade is at least present, and it isn’t usually found in deforested habitat. This bird is vulnerable to predation from humans, dogs, rats, and other animals.
Other: Because the Long-Tailed Ground-Roller lives in such a limited habitat, it is extremely vulnerable to extinction; habitat destruction and habitat quality decline has led to extensive drops in its population. No part of its habitat is currently being preserved, creating an area that most needs conservation efforts. It was a common bird at the beginning of the 1900s, but today is considered rare, between 10,000 and 33,000 birds left; ongoing conservation efforts are poor, and it is only kept in one zoo.
~ By Meig Dickson
Sources under the Cut
Jobling, J. A. 2010. The Helm Dictionary of Scientific Bird Names. Christopher Helm Publishing, A&C Black Publishers Ltd, London.
Langrand, O. & Kirwan, G.M. (2019). Long-tailed Ground-roller (Uratelornis chimaera). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.
