摘要
Species that overlap in their morphologies are sometimes difficult to distinguish from one another, which can complicate species’ conservation and management. The Little Brown Bat (Myotis lucifugus) and Yuma Myotis (Myotis yumanensis) are sympatric in parts of their range in western North America, and they overlap in morphology, making them difficult to tell apart in the hand in some areas, such as the Pacific Northwest. We compared various methods of distinguishing between M. lucifugus and M. yumanensis to genetic results, using a blind test approach to remove observer bias. Using multiple independent observers, we used external morphology and echolocation-call structure to classify bats from a maternity colony consisting of both species. Genetic analysis confirmed 13 M. lucifugus and 40 M. yumanensis. Minimum echolocation-call frequency separated 100% of M. lucifugus from M. yumanensis using a cut-off of 43 kHz. All M. lucifugus had a minimum echolocation-call frequency ≤42.8 kHz, whereas M. yumanensis had a minimum frequency ≥44.55 kHz. There was some overlap in forearm length; a cut-off of 36 mm would have correctly identified 77% of M. lucifugus and 100% of M. yumanensis to species. Criteria based on subjective assessment of fur sheen and length as well as ear color were moderately successful (90.5 and 77% success by 2 separate observers) in distinguishing between the 2 species. The use of Munsell soil color charts and multivariate statistics to classify fur and membrane color and confirm species identification was not successful. Our results suggest that mean minimum call frequency alone is sufficient for distinguishing between M. lucifugus and M. yumanensis. Use of quantitative rather than qualitative criteria eliminates observer bias and appears to be better for identifying these 2 species.
摘要译文
重叠在它们的形态中的物种有时难以彼此区分，这可以使物种的保护和管理复杂化。小棕色蝙蝠（Myotis lucifugus）和yuma myotis（myotis yumanensis）是在西北西部的一部分的合作伙伴，他们在形态中重叠，使他们难以在一些领域分开，如太平洋西北。我们使用盲试验方法比较了各种区分M. Lucifugum和M. yumanensis的方法，以消除观察者偏差。使用多个独立观察者，我们使用外部形态和呼应呼叫结构，将蝙蝠分类为来自两种物种组成的产妇群体。遗传分析证实了13米荧光飞术和40米。尤曼森。最小回声定位呼叫频率使用43 kHz的截止值将100％的M.荧光蛋白分离。所有M.Lucifugus都有最小的回声呼叫频率≤42.8kHz，而M. yumanensis的最小频率≥44.55kHz。前臂长度有一些重叠;截止36毫米将正确地确定77％的M.Lucifugus和100％的M. Yumanensis到物种。基于毛皮光泽和长度的主观评估的标准以及耳朵颜色的中度成功（通过2个单独的观察者成功90.5％和77％），以区分2种。使用Munsell土壤图和多元统计数据来分类毛皮和膜颜色，确认物种鉴定并未成功。我们的结果表明，单独的平均呼叫频率足以区分M.荧光素和M. yumanensis。使用定量而不是定性标准，消除了观察者偏差，并且似乎更好地识别这2种。
Tanya MJ Luszcz[1;*]; Jason MK Rip[1]; Krista J Patriquin[1]; Lydia M Hollis[1]; Joanna M Wilson[1]; Heather DM Clarke[1];. A Blind-Test Comparison of the Reliability of Using External Morphology and Echolocation-Call Structure to Differentiate Between the Little Brown Bat (Myotis lucifugus) and Yuma Myotis (Myotis yumanensis)[J]. Northwestern Naturalist, 2016,97(1): 13-23