The omnivorous diet of the western chicken turtle (Deirochelys reticularia miaria)

Abstract

Chicken Turtles (Deirochelys reticularia) are morphologically adapted for carnivory, and this specialization has been corroborated by diet studies of the eastern and Florida subspecies (D. r. reticularia and D. r. chrysea, respectively). However, the diet of the western subspecies (D. r. miaria) has not been examined. To investigate this important aspect of this subspecies' ecology, we collected 54 fecal samples from 22 adult D. r. miaria and 13 samples from nine juvenile D. r. miaria in southeastern Oklahoma. White River Crayfish (Procambarus acutus) were found in 88.9% of adult samples (mean of 2.3 crayfish per sample), and appeared to be the dominant food source for adults. There was a significant positive relationship between turtle size and crayfish size, and on average the crayfish were 29.8 mm in carapace length. Insects representing six orders (predominantly Hemiptera and Coleoptera) were found in 57.4% of adult fecal samples. Surprisingly, plants were present in 92.6% of adult fecal samples. While most of the plant matter was unidentifiable, Common Rush (mostly seeds; Juncus effusus), Broadleaf Cattail (Typha latifolia), Giant Cutgrass (seeds; Zizaniopsis miliacea), and Purple-fringed Riccia (Ricciocarpus natans) were identified in several fecal samples. There was a significant difference between the diets of juveniles and adults, with juveniles consuming more insects, fewer crayfish, and fewer plants than adults. These results suggest both that there is an ontogenetic shift in the diet of D. r. miaria and that, unlike the other subspecies, D. r. miaria is demonstrably omnivorous.

Department(s)

Biology

Document Type

Article

DOI

https://doi.org/10.1643/CH-14-072

Publication Date

5-1-2015

Journal Title

Copeia

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