Surveying drainage culvert use by carnivores: sampling design and cost-benefit analyzes of track-pads vs. video-surveillance methods

摘要: Environmental assessment studies often evaluate the effectiveness of drainage culverts as habitat linkages for species, however, efficiency sampling designs and survey methods are not known. Our main goal was to estimate most cost-effective monitoring method carnivore culvert using track-pads video-surveillance. We estimated efficient (lower costs high detection success) interval between visits (days) when also determined advantages each method. In 2006, we selected two highways in southern Portugal sampled 15 over 10-day periods (spring summer). Using track-pad method, 90% animal tracks were detected a 2-day visits. recorded higher number crossings species video-surveillance (n = 129) compared with technique 102); ability varied type structure species. More circular (1 m 1.5 diameter) than box (2 4 width), likely because video cameras had reduced vision coverage area. On other hand, small feet such common genet Genetta genetta less surveying The cost–benefit analyzes shows that is appropriate technique, but allows year-round surveys well behavior response crossing structures.