Ecological parameters of Coluber constrictor etheridgei, with comparisons to other Coluber constrictor subspecies

Abstract

In 1998, we conducted a radio-telemetry study of Coluber constrictor

etheridgei (Tan Racer) in the Angelina National Forest in eastern Texas. Individuals

were located once daily from 12 June to 14 August. We determined home-range

size, movement distances, movement frequency, and habitat use for this short-term

study. We also determined food habits of this population by examination of fecal

samples. We compared these parameters to other Racer taxa in Utah (C. c. mormon

[Western Yellow-bellied Racer]), Kansas (C. c. fl aviventris [Eastern Yellow-bellied

Racer]), and South Carolina (C.c. priapus [Southern Black Racer]). Compared to

these populations, Texas Racers exhibited larger home ranges and greater movement

frequency and distances during the summer than Utah or Kansas populations, but approximately

equal to those of the South Carolina population. Available data on food

habits suggests that all populations are consumers of invertebrate and vertebrate prey.

We hypothesize that the basic diet of C. constrictor is composed of invertebrates captured

by active foraging in areas of abundant herbaceous vegetation, that differences

in home-range size and movement distances result from variations in patchiness of

suitable foraging habitat across populations, and that the proportion of vertebrate

prey in the diet of Coluber populations increases as home-range size and movement

distances increase due to increasing patchiness of foraging habitat, resulting in

increasing encounters with vertebrate prey.

Citation

Fleet, Robert R.; Rudolph, D. Craig; Camper, J. D.; Niederhofer, J. 2009. Ecological parameters of Coluber constrictor etheridgei, with comparisons to other Coluber constrictor subspecies. Southeastern Naturalist 8(Special Issue 2): 31-40.