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Anthropogenically driven environmental change has imposed substantial threats on biodiversity, including the emergence of infectious diseases that have resulted in declines of wildlife globally. In response to pathogen invasion, maintaining diversity within host populations across heterogenous environments is essential to facilitating species persistence. White-nose syndrome is an emerging fungal pathogen that has caused mass mortalities of hibernating bats across North America. However, in the northeast, peripheral island populations of the endangered northern myotis (Myotis septentrionalis) appear to be persisting despite infection while mainland populations in the core of the species range have experienced sharp declines. Thus, this study investigated host and environmental factors that may contribute to divergent population responses. We compared patterns of pathogen exposure and infection intensity between populations and documented the environmental conditions and host activity patterns that may promote survival despite disease invasion. For island populations, we found lower prevalence and less severe infections, possibly due to a shorter hibernation duration compared to the mainland, which may reduce the time for disease progression. The coastal region of the northern myotis range may serve as habitat refugia that enables this species to persist despite pathogen exposure; however, conservation efforts could be critical to supporting species survival in the long term.
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Wing Measurements for Differentiating Three Cryptic Species of Myotis (Mammalia: Chiroptera) that Co-occur in the Southeastern United States
Identification of cryptic species often relies on invasive techniques such as comparison of cranial morphology or generation of DNA sequences. Myotis lucifugus and M. septentrionalis recently have been reported to occur near the Texas border in Oklahoma and Louisiana, respectively, and due to similarity of appearance, both species easily could be mistaken for M. austroriparius, a common inhabitant of East Texas. All three species co-occur across much of the southeastern United States. Myotis septentrionalis recently was listed under the Endangered Species Act as Endangered, and M. lucifugus has seen drastic reductions in abundance due to white-nose syndrome. Therefore, special care is needed when capturing any of these species due to the cryptic nature of their external morphology and the potential for misidentification in the field. The objective of this study was to determine if wing measurements obtained in the field could be used to differentiate among these three species. Measurements of 13 wing elements from 45 museum specimens were compared using univariate and multivariate statistics. Significant multivariate differences among species were detected, indicating that some wing characteristics may be effective for differentiation. These wing characteristics were compiled into a dichotomous key that researchers can use to easily identify species in the field. Using this technique, non-target species can be released quickly without harm, whereas individuals of species of interest can be confidently collected for scientific research.
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- Award ID(s):
- 2101909
- PAR ID:
- 10555416
- Editor(s):
- Bradley, R D
- Publisher / Repository:
- Occasional papers Museum Texas Tech University
- Date Published:
- Journal Name:
- Occasional papers Museum Texas Tech University
- Edition / Version:
- 1
- Volume:
- 388
- Issue:
- 1
- ISSN:
- 0149-175X
- Page Range / eLocation ID:
- 1-11
- Subject(s) / Keyword(s):
- cryptic species, Myotis austroriparius, Myotis lucifugus, Myotis septentrionalis, species identification, wing measurements, wing morphology
- Format(s):
- Medium: X Size: <10mb Other: pdf
- Size(s):
- <10mb
- Sponsoring Org:
- National Science Foundation
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