Health & Environmental Research Online (HERO)


Print Feedback Export to File
8035239 
Journal Article 
Shifty salamanders: transient trophic polymorphism and cannibalism within natural populations of larval ambystomatid salamanders 
Jefferson, DM; Ferrari, MC; Mathis, A; Hobson, KA; Britzke, ER; Crane, AL; Blaustein, AR; Chivers, DP 
2014 
Yes 
Frontiers in Zoology
ISSN: 1742-9994 
11 
1 
76 
English 
25337147 
WOS:000345799800001 
INTRODUCTION: Many species of ambystomatid salamanders are dependent upon highly variable temporary wetlands for larval development. High larval densities may prompt the expression of a distinct head morphology that may facilitate cannibalism. However, few studies have characterized structural cannibalism within natural populations of larval salamanders. In this study we used two species of larval salamanders, long-toed (Ambystoma macrodactylum) and ringed salamanders (A. annulatum). Head morphometrics and stable isotopic values of carbon (δ(13)C) and nitrogen (δ(15)N) were used to identify the presence or absence of structural cannibalism. Weather conditions were also analyzed as a potential factor associated with the expression of cannibalistic morphology.

RESULTS: Populations of salamander larvae did not consistently exhibit cannibalistic morphologies throughout collection periods. Larval long-toed salamanders exhibited trophic polymorphisms when relatively lower precipitation amounts were observed. Larval ringed salamanders were observed to be cannibalistic but did not exhibit polymorphisms in this study.

CONCLUSIONS: Structural cannibalism may be transient in both species; however in long-toed salamanders this morphology is necessary for cannibalism. Ringed salamanders can be cannibalistic without morphological adaptations; however the cannibal morph may prolong the viable time period for cannibalism. Additionally, weather conditions may alter pond hydroperiod, subsequently influencing head morphology and cannibalism.