SMITH: GOPHERUSPOLYPHEMUSON THE ORDWAY PRESERVE


define specific conditions important in nest site selection and to identify alternative
nest sites. Alternative nest sites may be particularly important if egg predators are
able to use burrows as visual cues to locate nests. In order to provide suitable nest
and burrow sites, a prescribed burning program should be implemented. Summer
burns which mimic natural lightning fires remove dead litter and increase
production of herbaceous food plants (Platt et al. 1988).
 Mean clutch size and hatchling body mass differed in 1990 and 1991. The
differences observed may be related to nutritional constraints on females because of
the prolonged drought that occurred from 1985 to 1990. Long-term studies are
needed to differentiate between normal yearly variation and effects of
environmental perturbations such as drought.
 Management strategies should include monitoring (and control, if necessary
through hunting and trapping) of mammals that prey on tortoise eggs and
hatchlings. Human activities have favored small opportunistic predators such as
raccoons (Landers 1980). Small mammal predator populations are uncontrolled,
because large predators have been extirpated from most of their former range
(Marshall 1987; Means 1988). Therefore, hatchling and egg predators probably
exert more pressure on tortoise populations now than they have in the past. In
areas where tortoise numbers have been depleted, it may be necessary to protect
nests from predators and to head-start hatchlings in on-site enclosures.
 Under natural conditions, the low reproductive potential of gopher tortoises is
compensated by a long life span, low adult mortality and the persistence of
extensive, unaltered habitat (Means 1988). Human activities have altered habitat
and predator-prey relationships. Remaining tortoise populations and habitat must
be actively managed to ensure their survival. Long-term research on gopher
tortoise demographics is necessary to develop sound management practices. The
protection and management of gopher tortoise populations are particularly
important because there are implications beyond a single species. Simply acquiring
and protecting upland habitats are not sufficient measures for ensuring survival of
gopher tortoise populations. Tortoise habitat must be actively managed, because
habitat quality is critical to population survival (Cox et al. 1987; Breininger et al.
1988).

 LITERATURE CITED


 Alford, R. A. 1980. Population structure of Gopherus polyphemus in northern Florida. J. Herp. 14:177-182.
 Arata, A. A. 1959. Notes on the eggs and young of Gopherus polyphemus (Daudin). Quart. J. Florida Acad.
 Sci. 21:274-280.
 Auffenberg, W., and R. Franz. 1982. The status and distribution of the gopher tortoise (Gopherus
 polyphemus). Pp. 95-126 in R. B. Bury, ed. North American Tortoises: Conservation and Ecology,
 U.S. Fish Wildl. Serv., Wildl. Res. Rept. 12.
 Auffenberg, W., and J. B. Iverson. 1979. Demography of terrestrial turtles. Pp. 541-569 in M. Harless and
 H. Morlock, eds. Turtles: Perspectives and Research. John Wiley & Sons, Inc., New York.
 Auffenberg, W., and W. Weaver. 1969. Gopherus berlandieri in southeastern Texas. Bull. Florida State
 Mus., Biol. Sci. 13(3):141-203.


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