(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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