Predation risk and microhabitat selection by cave salamanders, Eurycea lucifuga (Rafinesque, 1822)

• Published in: Behaviour Vol. 155; no. 10-12; pp. 841 - 859
• Main Authors: Bradley, J. Gavin, Eason, Perri K
• Format: Journal Article
• Language: English
• Published: Leiden|Boston Brill 2018; BRILL; Brill Academic Publishers, Inc
• Subjects: Animal behavior; Caves; clay; Damage; energy; Eurycea lucifuga; foraging; Foraging habitats; Forests; habitat preferences; Habitat selection; Habitats; Microenvironments; Microhabitats; Predation; Risk; salamanders and newts; Substrates; Tradeoffs
• ISSN: 0005-7959; 1568-539X; 1568-539X
• DOI: 10.1163/1568539X-00003505

Abstract Habitat selection is driven by many factors, but no one location is likely to be best for all factors; thus, individuals are subject to trade-offs when selecting habitat. Caves provide a clear example of such trade-offs because these habitats are energy deprived. Cave salamanders (Eurycea lucifuga) commonly inhabit caves at least in part because this habitat is cool and wet. We tested the hypothesis that caves also provide cave salamanders with a reduction in predation risk. We used clay models to test for differences in predation risk in caves vs. forests and at low (e.g., ground) vs. elevated (e.g., cave wall) positions, and recorded locations of cave salamanders to assess vertical (i.e., wall) vs. non-vertical (e.g., ground) substrate selection in a cave. Overall, a mean of 3.2 models in caves were damaged and a mean of 8.2 were damaged in forests. Cave salamanders selected vertical substrate more often than non-vertical substrate ( χ 2 = 794.53, p < 0.001), and in caves, low-positioned models were more likely to be damaged than models on walls, although there was no effect of model height in forests. This study suggests that caves provide salamanders a refuge from increased predation pressure, a benefit that likely compensates for the costs of moving between caves and the richer foraging grounds outside them.