Monday, 8 July 2013

Diverse Movement Patterns of North America’s Eastern Box Turtle (Terrapene carolina carolina L.). Part 1: Extremes of High and Low Site Fidelity Susan Seibert1 and William R. Belzer2 - via Herp Digest

(Editor-Anyone interested in the problem of relocation of box turtles should download this article and probably their published work on this project in future issues in ICRF)
To Download this article (22 pages with photos and maps) go to 

1AA Forestry and Wildlife Service, Inc., 2270 Raymilton Road, Utica, Pennsylvania 16362, USA (turtletracker@windstream.net
2Eastern Box Turtle Conservation Trust, 304 East Bissell Avenue, Oil City, Pennsylvania 16301, USA (billbelzer@hotmail.com; corresponding author) 
Photographs by the authors unless otherwise noted. 

Twenty years ago (1993), we started tracking the movements of displaced adult (and, later, headstarted juvenile) Eastern Box Turtles (Terrapene carolina carolina) released into two different nature sanctuaries in northwestern Pennsylvania, USA (Belzer 1996, Belzer and Steisslinger 1999, Belzer and Seibert 2009a). Our project strives to discover whether releasing adult and headstarted juvenile turtles might be a practice that could rebuild decimated and extirpated box turtle populations (Belzer 2002, 2008; Belzer and Seibert 2009a). Extant knowledge of the long-term habitat use by box turtles had been developed largely by annual and decennial censuses of several different populations (Stickel 1950, 1978, 1989; Schwartz and Schwartz 1974; Kiester et al. 1982; Schwartz et al. 1984; Williams and Parker 1987; Hall et al. 1999; Schwartz 2000). Whereas some box turtles in these long-term studies were observed to shift the position of their home ranges, and other (“transient”) individuals arrived in and then passed through an established population’s habitat, high site fidelity within relatively small parcels of habitat was seen to be normative for this species. Stickel (1989) stated that locations of home ranges of adult turtles were generally stable across 29 years, while Schwartz et al. (1984) noted that once a turtle establishes a home range, it becomes so well acquainted with the features of it that gradual successional changes in the vegetation are tolerated and have little influence on home range. Repeat encounters with ultra-centenarian box turtles at their earlier sites after many intervening decades (Graham and Hutchison 1969, Lovewell 1989, National Park Service 2005) also supported the impression that high site fidelity is the norm. 

Consequently, we anticipated that once we observed highly consistent habitat use by a released individual over several consecutive years, we would essentially have demarcated the adoptive home range for that turtle, and we could remove its radiotransmitter, secure in the assumption that it would continue to use that parcel of habitat indefinitely. Our weekly monitoring of movements across decades, however, has revealed highly distinctive and sudden changes in patterns of habitat use. We now recognize that frequent observations over protracted periods are necessary to disclose the real spectrum of how individuals of this species use habitat. Conclusions about habitat preferences derived from less intensive monitoring can be misleading. 

Pooling our movement data for the more than 100 turtles that we have intensively monitored for lengthy periods tends to conceal remarkable differences in habitat use. Each turtle is its own case study. In order to better divulge distinctive details about how different individuals use their habitat, we plan to publish a series of articles in this journal, each of which will examine relatively few turtles. This first installment in the series focuses on the turtles that displayed extremes of very high or very low site fidelity. As the series progresses, types of behavioral variation that are exhibited by other turtles within those extremes will increasingly emerge.

To Download the full 22 page article with photos and maps go to 
http://www.ircf.org/journal/volume-20-no-2-june/ 

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