Title
Abundance and population structure of Podocnemis erythrocephala (Testudines, Podocnemididae) in the Unini River, Amazonas
Author(s)
Bernardes, V. C. D.;Ferrara, C. R.;Vogt, R. C.;Schneider, L.
Published
2014
Publisher
Chelonian Conservation and Biology
Published Version DOI
https://doi.org/10.2744/CCB-1039.1
Abstract
We studied the population structure, sex ratio, and abundance of a locally endangered species of freshwater turtle, the red-headed river turtle (Podocnemis erythrocephala), in the Unini River in Negro River Basin in Brazil with capture-recapture of marked individuals in 1 yr, including both dry and rainy seasons. We used trammel nets of 3 different inner mesh sizes in the lakes. The nets were revisited at 3-hr intervals from 0600 to 1800 hrs each day. All turtles were released after being marked, measured, and sexed. During the study, 352 individuals were marked including 162 males, 150 females, and 40 immatures. The majority of the turtles (79%) were captured in the dry season when the water level of the river was declining. Mean standard deviation straight-line carapace length was 210 +/- 14 mm (range 163-262 mm) for males and 251 +/- 18 mm (221-303) for females. Most turtles captured were in the intermediate size classes: 200-210 mm for males and 230-270 mm for females. The sex ratio of adults in this population was 1.05 males per female, not significantly different from 1: 1. Only 12 turtles were recaptured, each once: 5 males, 5 females, and 2 immatures. The population showed recruitment and the adults are in equilibrium; however, few turtles were captured in the smallest or largest size classes.

Access Full Text

A full-text copy of this article may be available. Please email the WCS Library to request.



Back

PUB15029