Black Vulture

Distribution

Breeding regions are NA, MA, SA. Breeding subregions are widespread.

IOC World Bird List, v

description

Description. The bone displays adult features including a distinct crista and fossa trochanteris, articular facet for the antitrochanter, and femoral head with the neck and the fovea ligamentum capitis developed, but it is clearly immature in that the exposed shaft is densely covered with short, fine striations, the fossa trochanteris is spongy, and the head retains dense, fine pores. It agrees remarkably in size, form and fine morphological details with Coragyps atratus, including the shaft curvature, proportions of the proximal end including the thick neck, the sharp and moderately elevated form of the crista trochanteris, and the proximal placement of the pneumatic foramen on the cranial surface. Larger than Cathartes aura and with the femur shaft distinctly bowed rather than straight as in that species. An immature individual of H. leucocephalus with similar bone surface textures (USNM BIRDS 611757 f) has a much longer femur (length from trochanter to the prominent nutrient foramen on the caudal aspect of the shaft, 57.7 mm in H. leucocephalus vs. 37.0 in the fossil) but is less advanced towards adult morphology (e. g., femoral head much less produced, crista trochanteris not d

The Irvingtonian Avifauna of Cumberland Bone Cave, Maryland

discussion

Remarks. The late Pleistocene (Rancholabrean) species C. occidentalis, is known from multiple localities in southwestern North America and is believed to have become extinct along with the Pleistocene megafauna (Brasso & Emslie 2006). Bones of this species are larger on average than in modern C. atratus (Howard 1962, 1968; Frailey 1972). Because the fossil femur has not attained adult surface textures, we cannot exclude the possibility that its full adult size would be above the range of modern C. atratus and within the range of the larger late Pleistocene species. It is notable that C. atratus has not moved into most of the southwestern range of C. occidentalis in the time since the extinction of the latter, roughly ten thousand years ago. This suggests that C. occidentalis occupied arid habitats that are not suitable for C. atratus. The immature bone of C. atratus provides evidence that the species was breeding in or near the cave. We can rule out the possibility that the bird had flown from elsewhere to reach Cumberland Bone Cave by analogy with a growth series of California Condor (G. californianus) skeletons. The developmental stage of the fossil most closely matches that of a

The Irvingtonian Avifauna of Cumberland Bone Cave, Maryland