CAPTURING COMMON RAVENS AND TRACKING BREEDING-SEASON MOVEMENT PATTERNS | |||
| Charles G Meyer; U.S. Geological Survey & Oregon State University; charlie.meyer14@gmail.om; Peter S. Coates, Jonathan B. Dinkins | |||
The common raven (Corvus corax; raven) is an extremely intelligent generalist avian predator known for exceptional intelligence with a high degree of behavioral flexibility, allowing for populations to exploit anthropogenic resources for nesting and forage. In the American West, raven populations have increased substantially in recent decades, especially in sagebrush ecosystems where they are the primary nest predator of greater sage-grouse (Centrocercus urophasianus; sage-grouse). Predation by over-abundant ravens on sage-grouse is a key factor contributing to documented sage-grouse population declines throughout the range. In this project, we sought to capture territorial, breeding ravens on their nests and fit them with GPS units to track their hunting patterns during the breeding season. We selected a field site identified by wildlife managers as an area where raven predation poses a primary threat to sage-grouse population sustainability. However, ravens are highly neophobic, making capture efforts challenging. Using several trapping techniques, we successfully captured three breeding ravens with high-powered lights and CO2-powered net gun. Here, we present methods for capturing breeding ravens, preliminary movement patterns during nesting and fledgling stages, and present early estimates of home-range size during the breeding season. These findings are preliminary, subject to change, and provided for best timely science. | |||
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