BULLETIN FLORIDA MUSEUM NATURAL HISTORY VOL. 38 PT. 1(4)


 Activity patterns.-- Radio-instrumented female tortoises rarely were
observed above ground. Of 5199 observations, tortoises were seen at the surface
only 97 times (< 2% of all observations). When encountered at the surface, female
tortoises most often were basking (76.4%) on or near the burrow apron, followed
by walking (16.5%), feeding (4.1%), nesting (1%) and mating (1%). Most
observations of basking behavior occurred in March (18.9%) and June (13.5%).
 Telemetered tortoises were active in all months of the year. However, the
number of active days (indicated by disturbance to sticks set at burrow entrances)
were highest from March through November (Fig. 3). Most incidental captures of
tortoises occurred from May to October (Fig. 4). Nearly 52% of all females were
caught in May and June during peak nesting season. Captures of males were high
from May through October and probably reflects long-range breeding forays.
Breeding has been reported from February through October (Dietlein and Franz
1979; Iverson 1980; Diemer 1986; L. Smith field notes) and is thought to peak in
spring and fall (Taylor 1982b).
 Mean number of burrows used per month by telemetered females ranged from
1.1 in January and October to 1.6 in May at the height of the reproductive season.
The number of burrows used and inter-burrow movements were greatest from May
through September (Fig. 5). Females in sandhill habitat had more than three times
as many inter-burrow movements in June as did old field females. Movements of
sandhill females in July and August were nearly twice as frequent as old field
tortoises. Relocation during summer months probably was related to the
availability of food. Herbaceous vegetation is unevenly distributed in sandhills and
preferred foods may be depleted during mid-to-late summer causing tortoises to
relocate. At a southwest Georgia sandhill site, adult tortoises migrated in late
summer as food resources became scarce (McRae et al. 1981b).
 Nearly all observations of telemetered tortoises and incidental captures
occurred between 1000 and 1800 hrs with peak observations occurring between
1200 and 1400 hrs and 1600 and 1700 hrs (Fig. 6). Similar diel activity patterns
have been observed in north and south Florida tortoises (Clements 1956; Douglass
and Layne 1978).
 Home range and movements.-- Individual burrows were the focal point of
tortoise activity. All feeding activity occurred within 17 m of the burrow being used
at the time (n = 6, mean = 7.4 m, range = 2.4-16.6. SD = 5.0). The feeding radius
of telemetered females in sandhill habitat averaged 11.9 m (n = 4, range = 2.4-16.6
m, SD = 5.6) compared with 5.9 m for old field females (n = 12, range = 2.4-14.5,
SD = 3.6). Mean feeding radii of tortoises in the two habitats were not significantly
different (t = 1.75, df = 4, p > 0.05), although the sample size was small (n = 16)
because tortoises tended to retreat into burrows as I approached. At a Georgia
sandhill locality, 95% of all gopher tortoise feeding activity took place within 30 m
of the burrow and the mean feeding radius of 45 adult tortoises (including males)
was 13.0 m (McRae et al. 1981b). Gopher tortoises depend on burrows for