Secretive species are difficult to study and often of conservation concern, as exemplified by the Eastern
Hellbender (Cryptobranchus alleganiensis). Traditional methods for sampling Hellbenders involves moving rocks,
which damages essential habitat. Use and installation of artificial shelters has made studying Hellbenders less
dangerous for the animal and less disruptive to stream habitat; however, researchers using shelters generally
capture occupying animals to identify them. We tested the ability of a submersible portable Passive Integrated
Transponder (PIT) antenna to accurately detect PIT-tagged Hellbenders in shelters. We tested the effects of the
presence and depth of cover rocks on top of shelters, PIT tag location within the shelter, and tag orientation on
detection efficiency of Hellbenders. For the 32 shelters occupied by a tagged individual with cover rocks in place,
the scanner accurately detected 31% of the animals versus 88% when cover rocks were removed. The detection
efficiency of the scanner dropped below 50% once cover rock depth exceeded 11 cm. Tags placed near the interface
of the entrance tunnel and chamber, or along the chamber walls, had higher detection efficiencies than those in
other locations within the shelter. Vertically oriented tags were 18% more likely to be detected than horizontally
oriented tags. Our study demonstrates that while this technology has certain limitations, it shows potent
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Environmental DNA improves Eastern Hellbender ( Cryptobranchus alleganiensis alleganiensis ) detection over conventional sampling methods
Effective conservation planning relies on accurate species detection. However, conventional sampling methods used for detecting rare and cryptic aquatic species suffer from low probabilities of detection. Environmental DNA (eDNA) has emerged as an innovative and powerful sampling tool for detecting aquatic species, with previous studies suggesting a detection advantage over conventional sampling. However, comparative studies often fail to consider the appropriate sampling frameworks to adequately compare sampling methodologies and account for the influence of environmental variables on eDNA detection probabilities. In this study, we paired two detection methods (eDNA and physical sampling) at 22 sites in West Virginia, USA, to compare the probability of detecting a cryptic, elusive, and imperiled species of giant salamander, the Eastern Hellbender (
- NSF-PAR ID:
- 10460027
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Environmental DNA
- Volume:
- 1
- Issue:
- 1
- ISSN:
- 2637-4943
- Page Range / eLocation ID:
- p. 86-96
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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