COLONY MAPPING: A NEW TECHNIQUE FOR MONITORING CREVICE-NESTING SEABIRDS

摘要: Abstract Monitoring populations of auklets and other crevice-nesting seabirds remains problematic, although numerous methods have been attempted since the mid-1960s. Anecdotal evidence suggests several large auklet colonies recently decreased in both abundance extent, concurrently with vegetation encroachment succession. Quantifying changes geographical extent may be a useful alternative to monitoring population size directly. We propose standardized method for colony mapping using randomized systematic grid survey two components: simple presence/absence an density survey. A quantitative index was derived from frequency droppings feathers. This new used map on St. George Island southeastern Bering Sea results were compared previous efforts. Auklet presence detected 62 201 cells (each cell  =  2500 m2) by sampling randoml...