Filial cannibalism leads to chronic nest failure of eastern hellbender salamanders (Cryptobranchus alleganienesis)
Creators: name: Hopkins, William
name: Case, Brian
name: Groffen, Jordy
name: Brooks, George
name: Jachowski, Cathy Bodinof
name: Button, Sky
name: Halligan, John
name: O'Brien, Rebecca
name: Kindsvater, Holly
Publisher: name: Zenodo
Year: 2023

description: These data and code support the results in our accompanying manuscript. In species that provide parental care, parents will sometimes cannibalize their own young. Here, we quantified the frequency of whole-clutch filial cannibalism in a species of giant salamander (eastern hellbender; <em>Cryptobranchus</em> <em>alleganienesis</em>) that has experienced precipitous population declines with unknown causes. We used underwater, artificial nesting shelters deployed across a gradient of upstream forest cover to assess the fates of 182 nests at 10 sites over 8 years. We found strong evidence that nest failure rates increased at sites with low riparian forest cover in the upstream catchment. At several sites, reproductive failure was 100%, mainly due to cannibalism by the caring male. The high incidence of filial cannibalism at degraded sites was not explained by evolutionary hypotheses for filial cannibalism based on adult body condition or low reproductive value of clutches. Instead, larger clutches at degraded sites were most vulnerable to cannibalism. We hypothesize that high frequencies of filial cannibalism of large clutches in areas with low forest cover could be related to changes in water chemistry or siltation that influence parental physiology or that reduce viability of eggs. Importantly, our results identify a possible mechanism contributing to population declines and observed geriatric age structure in this imperiled species.
description: R programming language version 4.1.1 are needed to open and run the R software. Rstudio (free version of the IDE) may be useful. Newer versions of R may or may not compile Stan; see README for details. For the image files (.jpg) a photo viewer is needed. Preview on Mac OS or an open-source image viewer such as Image Glass (for Windows 10) can be used to view the photos once downloaded. For the movie files (.mp4) a movie player is needed. VLC is an open-source media player that works on both Windows and Mac platforms. Funding provided by: Virginia Department of Wildlife Resources*<br>Crossref Funder Registry ID: <br>Award Number: EP244309Funding provided by: National Science Foundation<br>Crossref Funder Registry ID: http://dx.doi.org/10.13039/100000001<br>Award Number: IOS-1755055Funding provided by: US Forest Service<br>Crossref Funder Registry ID: http://dx.doi.org/10.13039/100006959<br>Award Number: Funding provided by: Fralin Life Sciences Institute, Virginia Tech*<br>Crossref Funder Registry ID: <br>Award Number: Funding provided by: Global Change Center, Virginia Tech*<br>Crossref Funder Registry ID: <br>Award Number:
description: We used underwater, artificial nesting shelters deployed across a gradient of upstream forest cover to assess the fates of 182 nests at 10 sites over 8 years. We measured nest success using images and videos taken at different times of the year. The data included here have been checked for quality control. The analysis is available in the R script.