COBirders,
It was great to observe the Castlewood Canyon Black Vulture soaring for 15 minutes with Turkey Vultures yesterday, so thanks to those who provided daily updates. In the did you know category, Black Vultures, unlike Turkey Vultures, have a poor sense of smell so they often fly higher, often out of view (as reported here on COBirds), but why? BVs often fly higher in order to observe the lower-flying TVs that have incredible olfactory powers making them more adept at finding food. Once a carcass has been located by TVs, Black Vultures, at least when in groups, are more aggressive and often takeover a carcass. BVs roost communally and when those with extended crops fly out in the A.M., individuals who have been unsuccessful in finding food follow along increasing their chances of a meal. Research shows Black Vultures often return to the same carcass day-after-day, so if someone finds a large road kill, a strategic placement of it would perhaps be interesting to observe. >From Birds of North America Online we learn BVs do not use their feet while feeding as TVs to and they feed faster, often entering a carcass through different orifices, including sticking heads through eye sockets to gobble up entrails etc, but they are unable to open a carcass, so they must wait for other animals to do so. As expected from a bird spending time inside a carcass, they spend many hours of the day preening. They have been observed feeding on carcass maggots, gathering them one at a time like chickens pecking up grain. They are not exclusively carrion feeders but will take young herons and newly born livestock; in South America they are one of the most common species at garbage dumps where finding dead mammals is a given. In one study, BVs were observed to prefer palm oil fruits above carrion. BVs nest on the ground and they are frequently seen perched in the middle of the day by cattle watering troughs on which they land to drink. Their wing-loading is higher than in TVs, so while soaring in weak thermals they have to flap more frequently, often a good way to spot one in a flock of TVs. To many, vultures are far from being beautiful except maybe while soaring on thermals, but BVs are a very successful and understudied species. Bill Maynard Colorado Springs ____________________________________________________________ Click here for great quotes from top international movers! http://thirdpartyoffers.juno.com/TGL2141/fc/BLSrjpTMAuRfgXDNxbvAwmc89p7GC2ag4lKm11b9rcCiqYjIBXGHa7MojeQ/ --~--~---------~--~----~------------~-------~--~----~ Colorado County Birding: http://www.coloradocountybirding.com/ You received this message because you are subscribed to the Google Groups "Colorado Birds" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.as/group/cobirds?hl=en -~----------~----~----~----~------~----~------~--~---
