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Ecology of a Recently Discovered Population Segment of Blanding’s Turtles, Emydoidea blandingii, in Barren Meadow and Keddy Brooks, Nova Scotia

Lefebvre, José, Mockford, Stephen W., Herman, Tom B.
Canadian field-naturalist 2012 v.126 no.2 pp. 89-94
Emydoidea blandingii, females, gene flow, genetic analysis, genetic drift, genetic variation, home range, juveniles, males, nesting sites, overwintering, population structure, rivers, sex ratio, streams, surveys, territoriality, trapping, Nova Scotia
Blanding’s Turtles in Barren Meadow Brook and Keddy Brook are part of the Pleasant River population, the easternmost population currently recognized in Nova Scotia. Previous genetic analysis demonstrated restricted gene flow among the populations of Nova Scotia. The conservation of this genetic diversity is important to reduce genetic drift and bottleneck effects in these populations. Between 2006 and 2008, the population in Barren Meadow Brook and Keddy Brook was estimated using visual surveys, trapping, and radio-tracking. Over the three years, surveys yielded 69 individuals (14 females, 22 males, 29 juveniles, 4 undetermined). Capture-mark-recapture analysis using the Chapman variation of Petersen formulas for bi-census yielded population estimates of 88 Blanding’s Turtles. The sex ratio did not deviate significantly from 1:1. Applying minimum convex polygon (MCP) and kernel methods to radio-tracking data yielded preliminary estimates of home range size and location for males and females. Females had larger homes ranges, probably because of the limited availability of nesting sites in Barren Meadow and Keddy Brooks. New overwintering sites and three new nesting sites were identified. Home ranges of males did not overlap, and males seemed to show territorial behaviour. An expanded sample, particularly of males, is needed to improve the assessment of home ranges, movements, and behaviour. To date, conservation efforts in this population have focused on females. If home ranges of males in an expanded sample also do not overlap, then conservation of this population requires closer scrutiny of males and their population genetic structure.