Recommendations for photo-identification methods used in capture-recapture models with cetaceans

摘要: Capture-recapture methods are frequently employed to estimate abundance of cetaceans using photographic techniques and a variety statistical models. However, there many unresolved issues regarding the selection manipulation images that can potentially impose bias on resulting estimates. To examine potential impact these we circulated test data set dorsal fin from bottlenose dolphins several independent research groups. Photo-identification were generally similar, but selection, scoring, matching varied greatly amongst Based results make following recommendations. Researchers should: (1) determine degree marking, or level distinctiveness, use sufficient quality recognize animals distinctiveness; (2) ensure markings sufficiently distinct eliminate for “twins” occur; (3) stratify sets by distinctiveness generate series estimates investigate influence including varying degrees markings; (4) strive incorporate variability among analysts into capture-recapture estimation. In this paper summarize sources provide recommendations best practices natural in framework.