DOI: 10.5061/dryad.2189s
title: Data from: Habitat attributes associated with short-term settlement of Ozark hellbender (Cryptobranchus alleganiensis bishopi) salamanders following translocation to the wild

description: 1. Organisms associated with lotic systems rank among the most threatened
 because of global change. Although translocation is being increasingly
 applied as a conservation strategy, most studies have focused on survival
 and recruitment of individuals, and few have attempted to identify how
 habitat attributes influence short-term settlement of animals during the
 critical post-release period. 2. We demonstrate the application of
 resource selection modelling in an information theoretic framework to
 identify release-site characteristics that will increase the likelihood of
 settlement for a fully aquatic benthic stream salamander, the Ozark
 hellbender (Cryptobranchus alleganiensis bishopi). We fit discrete choice
 models using data from 29 radio-tagged hellbenders that were translocated
 to two sites in the North Fork of the White River (NFWR), Missouri
 (U.S.A.). We defined resource availability at two spatial scales (stream
 reach and home range) and quantified abiotic habitat attributes at 3181
 salamander locations and 6329 random available locations collected between
 May 2008 and August 2009. 3. At both sites and spatial scales, a single
 model received substantially greater support (0.96–1.00 of total model
 weight) than all other models, and top-ranked models were similar in form
 and predictive ability. At both spatial scales, selection was positively
 influenced by the presence of cobble-boulder substratum relative to
 bedrock and finer substrata. We also noted a negative interactive effect
 between distance to the nearest substratum particle large enough to
 provide cover (i.e. at least one axis ≥15 cm in length) and an increase in
 either a direct or relative (i.e. pool, run, and riffle) measure of water
 velocity. 4. Collectively, salamanders released in our study selected
 resources indicative of long-term benthic microhabitat stability. However,
 despite strong selection of cobble-boulder substratum, 8% (282 of 3181) of
 captive-reared hellbender locations occurred in bank crevices and root
 masses. Although several studies have reported the importance of near bed
 hydraulics in determining occurrence of stream macroinvertebrates, our
 findings are the first to indicate that spacing among cobble-boulder
 substrata may be important for hellbenders. 5. To increase the likelihood
 of short-term settlement of captive-reared hellbenders in the wild, we
 recommend prioritising release sites where the average distance between
 cobble-boulder particles within habitat patches is minimised. In general,
 average spacing among cobble and boulder substrata should be &lt;1 m
 in habitat patches where mean benthic water velocity exceeds 0.1 m s−1,
 and &lt;0.5 m where water velocity approaches 0.30 m s−1. Based on
 home range sizes of captive-reared Ozark hellbenders, the collective
 extent of suitable cobble-boulder habitat patches within release sites
 should approximate at least 10 m2 per salamander released.
description: Hellbender
 Data