Comparison of small-mammal sampling techniques in tidal salt marshes of the central gulf coast of Florida

摘要

Use of traditional small-mammal sampling techniques is challenging in coastal salt marshes and forests. Various conditions particular to this type of environment affect the efficacy of sampling efforts. We compared various indirect (no physical capture) and direct (physical capture) techniques coupled with different baits to determine an effective method for sampling small mammals. In 1440 trap-nights, Sherman live traps caught significantly more rodents than Fitch traps (112 versus 16 respectively, Fisher's exact test: P = 0.0103), but the relationship between bait types, which included oats, scratch feed, sunflower seeds and suet, was not as apparent. However, for practical reasons, scratch feed and sunflower seeds were best used in marsh conditions due to their water resistance and ease in clean-up. Both track and scat plates were unsuccessful due to water damage and destruction by nontarget animals. Cameras yielded limited success. Target small mammals were photographed 436 times, but of those, only 26 could be positively identified to species. However, with adjustments including improved lens quality and adjustable focus distance, this could become a useful tool for small-mammal sampling. Such improved remote cameras could offer a viable alternative when permits cannot be issued, field access is limited, or there are concerns about mortality of the target species.