Wood Turtle (Glyptemys insculpta) populations occupy a disjunct range throughout the northeastern United States and southeastern Canada (Ernst et al. 1994). Recent studies have demonstrated that Wood Turtle populations are undergoing significant declines (e.g., Garber and Burger 1995; Daigle and Jutras 2005; Saumure et al. 2007). Agricultural and recreational activities, poaching, shooting, as well as habitat destruction and fragmentation have been implicated as factors contributing to the decline of the species (e.g., Harding 1991; Garber and Burger 1995; Ernst 2001; Saumure et al. 2007).
Wood turtles are a long-lived species with delayed sexual maturity and relatively limited reproductive output (Brooks et al. 1992; Ernst et al. 1994; Walde et al. 2003), factors that will hinder recovery efforts. Sexual maturity is reached from 12 - 18 years of age at the northern limits of their range (Brooks et al. 1992, Saumure and Bider 1998; Walde et al. 2003). Although individual clutch sizes may vary from 5 - 18 eggs, clutch sizes typically average 8 - 11 eggs (e.g., Harding and Bloomer 1979; Farrell and Graham 1991; Ross et al. 1991). As a result of nest predation rates exceeding 80%, few data exist on natural nest success and recruitment (Harding and Bloomer 1979; Brooks et al. 1992). However, recruitment rates of 74 - 77% have been documented for eggs raised in incubators or nests protected by nest covers (Farrell and Graham 1991; Tuttle and Carroll 1997). Moreover, few studies have investigated the spatio-temporal aspects of nesting migrations (Arvisais et al. 2002) or nest-site fidelity. Efforts to protect this imperiled species are hindered by our lack of knowledge concerning its reproductive ecology (Bury 2006; McCallum and McCallum 2006).
Although the Wood Turtle has been protected throughout most of its range for many years (Levell 2000), it was only recently assigned the legal status of vulnerable in Québec (Gazette Officielle du Québec 2005). Although several studies have investigated the population ecology of Wood Turtles in Québec, none have focused on nesting ecology (Saumure and Bider 1998; Arvisais et al. 2002; Walde et al. 2003; Daigle and Jutras 2005; Saumure et al. 2007). The goal of our study was to document the nesting ecology of a large G. insculpta population at the northern limit of the species’ range. Specific objectives were to describe: (1) the movements of females to nesting areas; (2) nesting activities and chronology; (3) clutch size and frequency in relation to body size; (4) nest-site fidelity; (5) nest success; and (6) recruitment.
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