-Behavior
Sexual maturity and breeding behavior do not appear in the condor until 5 or 6 years of age. They may live for 50 years or more, and mate for life. The Andean condor prefers roosting and breeding at elevations of 3,000 to 5,000 m (10,000–16,000 ft). There on inaccessible ledges of rock, its nest consisting merely of a few sticks placed around the eggs, it deposits one or two bluish-white eggs.
There is a well developed social structure within large groups of condors, with competition to determine a ‘pecking order’ by body language, competitive play behavior, and a wide variety of vocalizations, even though the condor has no voice box.
Wild condors inhabit large territories, often traveling 250 km (150 miles) a day in search of dead animals. They prefer large carcasses such as deer or cattle which they spot by looking for other scavengers, who cannot rip through the tougher hides of these larger animals with the efficiency of the larger condor. In the wild they are intermittent eaters, often going for a few days without eating, then gorging themselves on several pounds at once, sometimes to the point of being unable to lift off the ground.
www.avianweb.com/andeancondors.html
The development of conservation strategies to protect viable populations of scavenging birds requires the existence of adequate and safe food supplies in the wild. Early reports on Andean condors Vultur gryphus diet recorded guanacos and rheas, the dominant herbivores since the Pleistocene, as their main food in Patagonia. However, in the past century, guanaco and rhea populations have notably decreased as a consequence of introduced livestock, and other exotic mammals have colonized the region. We study the spatial and temporal variation of the condors’ diet to determine which species are being consumed by condors, and to test whether native herbivores still have a role as a food source. We analysed 371 pellets (517 prey items), collected along 500 km in northwestern Patagonia, Argentina. Our study shows that the Andean condor depends heavily (98.5%) on exotic herbivores. Their diet was made up of c. 51% sheep/goat, 24% hare/rabbit, 17% red deer and 6% cow/horse, with only 2% other mammal species. Samples from locations surveyed after 12–15 years showed a diet shift coincident with the local tendencies in the food source. The diet composition of condors using roosts within the same zone was very similar, which suggests that they may be feeding from the same area. Thus, unhealthy carcasses could impact the entire local populations. Our results show the abundance of the invasive species in northwestern Patagonia and support the idea that native mega-herbivores are ecologically extinct in this area. Exotic species management can have a decisive impact on scavenger’s survival. It is necessary to apply a strategy that includes public environmental education about the problems of scavengers (e.g. use of poison, veterinary medicines and lead bullets), and a serious productive plan, including native species as a suitable source of economic development.
Spatial and temporal patterns in the diet of the Andean condor: ecological replacement of native fauna by exotic species
A. Lambertucci, A. Trejo, S. Di Martino, J. A. Sánchez-Zapata, J. A. Donázar, F. Hirald
http://onlinelibrary.wiley.com/doi/10.1111/j.1469-1795.2009.00258.x/abstract
Posted on August 9, 2010
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