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Snapping Turtle Conservation

On the assumption that drivers were har-
vesting Common Snapping Turtles
(Chelydra serpentina) crossing the roads,
almost invariably females searching for
nesting sites, TUCKER AND LAMER (2004.
Turtle and Tortoise Newsletter (8):10–11)
examined sex ratios of turtles collected in
three bodies of water in rural Illinois, two
near a heavily traveled road and one on a
National Wildlife Refuge, isolated from
heavy vehicular traffic. Preliminary results
indicated that the sex ratios in popula-
tions near the road where turtles are eas-
ily removed were heavily male-biased,
whereas that of the population not sub-
ject to adventitious collecting was essen-
tially 1:1. Also, sex ratios of Red-eared
Sliders (Trachemys scripta), which pre-
sumably are not subject to collection for
the cooking pot, were approximately 1:1
in all three lakes. The potential impact on
the effective breeding size of the affected
populations is severe. The authors recom-
mended that the harvest of Common
Snapping Turtles during the nesting sea-
son (May and June in Illinois) be prohib-
ited and that similar surveys be conducted
in other parts of the species’ range to
determine the range of this problem.

Road Mortality in European Vipers

In a study of road mortality of Lataste’s
Viper (Vipera latastei) and Iberian Adder
(V. seoanei) in a Portuguese national park,
BRITO AND ÁLVARES (2004. Amphibia-
Reptilia 25:459–465) reviewed a prob-
lem that affects many animals and pro-
posed some ameliorating actions. They

noted that road construction and accom-
panying vehicular traffic not only kill
animals, but also change behavior, frag-
ment habitats, create barriers, introduce
pollutants, enhance the spread of exotic
species, and increase human activity in
fragile landscapes. Affecting animals
ranging from invertebrates to large mam-
mals and aquatic, terrestrial, and aerial
species, road mortality modifies the
demography and population structure of
species and affects the recovery of endan-
gered species or contributes to the endan-
germent of others. Local management
strategies that could reduce the intensity
of road mortality, at least in national
parks or similar areas, include: (1) educa-
tional programs aimed primarily at chil-
dren (see, however, the summary of
Gomez et al. 2004 on this page), (2)
active removal of live animals from the
roads, (3) studies identifying the areas
where mortality is highest and erection of
warning signs, barriers to block animals
from entering those sections of road, and
under-road passages to allow safe transit.

Classroom Snake Talks and Attitudes
toward Conservation

In a Canadian study, GOMEZ ET AL.
(2004. Herpetological Review 35:338–
341) tested the assumption that class-

56 IGUANA  •  VOLUME 12, NUMBER 1  •  MARCH 2005 CONSERVATION RESEARCH REPORTS

C O N S E R V A T I O N  R E S E A R C H  R E P O R T S

Snapping Turtles are usually aquatic, rarely venturing out of the water. However, during the
nesting season, females often range widely in search of suitable nesting sites. This adult female
had recently emerged from a small lake when photographed. Photograph by Robert Powell.

Reptiles are particularly vulnerable to road mortality due to thermoregulatory needs that favor
the use of heat-retaining paved roads as heating surfaces, relatively slow locomotion, and migra-
tory patterns exhibited by some species. This Prairie Kingsnake (Lampropeltis calligaster) was
killed in Christian County, Missouri. Photograph by Brian S. Edmond.



IGUANA  •  VOLUME 12, NUMBER 1  •  MARCH 2005 57CONSERVATION RESEARCH REPORTS

room “snake talks” (interpretive pro-
grams) effectively alter grade-2 children’s
attitudes toward snakes and conservation.
Results of the carefully designed study,
implemented with full cooperation of the
local public schools, showed that a “sur-
prisingly high positive mean-attitude
score” immediately and shortly after the
presentations had returned to much
lower pre-program levels within a week,
and remained there until the end of the
study two months later. The only excep-
tion to this general trend was an
improved perception about touching
snakes. “Although this positive attitude
change did not influence the students’
overall attitudes towards snakes, it still
may have helped shape their ‘mental pic-
ture’ of them.” The authors suggested
that interpretive programs should not be
discontinued and that periodic revisiting
of the topic might improve results, but
that caution should prevail until addi-
tional, possibly longer-term studies
address unanswered questions regarding
the effectiveness of snake talks.

Endangered St. Croix Ground
Lizards on Green Cay

The St. Croix Ground Lizard (Ameiva
polops) was listed as endangered by the
U.S. Fish & Wildlife Service in 1977,
and the population on Green Cay had
not been surveyed since the mid-1990s.
MCNAIR AND LOMBARD (2004.
Caribbean Journal of Science 40:
353–361) conducted surveys and con-
servatively estimated the population at
183 lizards, which suggested a decline in
the long-term population size. The pres-
ence of lizards was positively associated
with greater numbers of shrubs. Ground
Lizards were more abundant than
expected in forested areas in the southern
half of the cay, but less numerous than
anticipated on beaches. The authors rec-

ommended additional population sur-
veys using a variety of methods to moni-
tor the population and assess ongoing
effects of hurricanes. (Note that a PDF
file of the entire article is available at
www.caribjsci.org).

TSD in River Terrapins

A long-standing conservation program in
Malaysia for the critically endangered
River Terrapin (Batagur baska) may be
hampered by the fact that clutches of
headstarted animals raised from artificially
incubated eggs and later released to the
wild may be all male or all female. 
HENG (2005. Turtle Survival Alliance

Communiqué 2(1):1–2) described stud-
ies by Dr. Gerald Kuchling, University of
Western Australia, who used non-lethal
endoscopy to examine animals from three
headstart facilities on opposite coasts of
Malaysia. He concluded that animals
from eggs incubated indoors in styrofoam
boxes tended to be all male, whereas those
produced by outdoor in-ground incuba-
tion were sometimes all female and some-
times a combination of both sexes, possi-
bly reflecting the ambient temperatures in
different years. Incubation trials are being
conducted to further investigate temper-
ature-dependent sex determination
(TSD) in this species.

Ameiva polops from Green Cay. Photograph by Amy Mackay. (Ms. Mackay is a Ph.D. candidate
at the Maryland Cooperative Fish and Wildlife Research Unit, University of Maryland Eastern
Shore, and her dissertation deals with the Green Cay population of A. polops).

Critically endangered River Terrapin (Batagur baska). Photograph by Chris Tabaka, DVM.

Attitude assessment instrument used to
quantify children’s reactions.




