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118 IGUANA  •  VOLUME 15, NUMBER 2  •  JUNE 2008

Herpetofaunal Use of Riparian 
Buffer Zones in South Africa

Habitat transformation is a growing
threat to global biodiversity. Many
species in South Africa, including reptiles
and amphibians, are threatened by
broad-scale habitat transformation as
habitats are converted to agricultural
uses. Understanding how wildlife uses
these landscapes is critical for effective
land management and for predicting
how populations might react to further
changes in habitat quality. MARITZ AND

ALEXANDER (2007. African Journal of
Herpetology 56:163–169) surveyed her-
petofaunal species richness and abun-
dance in riparian and non-riparian habi-

tats to determine how these animals uti-
lize different habitats within agricultural
landscapes near Mtunzini, KwaZulu-
Natal, South Africa. Riparian areas had a
higher mean species richness and abun-
dance than adjacent agricultural areas,
and hosted 80% of all herpetofaunal
species detected. Ten species were unique
to riparian areas, including snakes,
lizards, and frogs. In contrast, non-ripar-
ian areas hosted only four unique species.
These results indicate that conversion to
agriculture is not desirable from a her-
petological conservation perspective, and
that preserved riparian areas can serve as
corridors for herpetofaunal species to sur-
vive and migrate through otherwise less
hospitable terrain.

Habitat Disturbances Affect 
Growth Rates in Turtles

Disturbances often help structure ecolog-
ical communities, and their effects may
have consequences on population
dynamics and long-term species persist-
ence. Should disturbances affect
resources, a trade-off may result between
reproduction and individual growth,
which could affect the timing of sexual
maturity in animals dependent on reach-
ing a requisite size for the onset of matu-
ration. DODD AND DRESLIK (2008.
Journal of Zoology 275:18–25) used a 14-
year mark-recapture dataset to determine
the effects of catastrophic storms and the
removal of nonindigenous vegetation on
individual growth rates of a long-lived
turtle, Terrapene carolina bauri. Adult
male growth rates increased 19% after
the disturbances, whereas female growth
rates decreased by a similar percentage.
Juvenile growth rates briefly increased,
but as these animals became subadults,
their growth rates slowed after distur-
bance, a change more pronounced in
females than males. After the distur-
bances, the onset of male sexual maturity
decreased by about 1 year (from 10.8 to
9.5 years), female maturity was delayed
by 2.5 years (from 8.5 to 11.0 years), and
the subadult life stage was extended from
2 to 3.5 years. With resources and habi-
tats similarly available to adults, the
authors suggested that adult females
diverted resources from growth to repro-

duction, whereas males allocated avail-
able resources to growth. Subadult
growth rates decreased regardless of sex,
implying that fewer or lower quality prey
were available to smaller turtles in the
years following disturbance. The results
of this study suggest that habitat distur-
bances affected individual growth rates
differently according to sex and life stage,
which affected the timing of maturation.
In long-lived vertebrates, such perturba-
tions on life-history traits such as growth
rates likely affect population recovery,
and may help to explain why turtle pop-
ulations recover slowly following cata-
strophic disturbance, even when adult
survivability is high.

Alligator Snapping Turtles in
Oklahoma and Kansas

Alligator Snapping Turtles (Macrochelys
temminckii) historically occurred in the
Arkansas, Caney, Verdigris, Neosho, and
Spring river drainages of northern
Oklahoma and southern Kansas. High
harvest rates in Oklahoma and river
impoundments in both states have
greatly reduced turtle numbers by deci-
mating populations and impeding disper-
sal routes. Populations of M. temminckii
are poorly studied in both states, but par-
ticularly so in Kansas. Management
efforts for M. temminckii were initiated in
Oklahoma in 1997 with the collection of
information on distribution, habitat use,
and population structure, and establish-
ment of a captive breeding/headstart pro-
gram. Management efforts in Oklahoma

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

CONSERVATION RESEARCH REPORTS

Amblyodipsas polylepis, Lycodonomorphus rufu-
lus, and Philothamnus hoplogaster (from top)
were captured in riparian areas only, whereas
Mehelya nyassae (bottom) was detected in
both habitat types.

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After disturbances (catastrophic storms and
removal of vegetation), the onset of male sex-
ual maturity in Florida Box Turtles (Terrapene
carolina bauri) decreased by about 1 year,
female maturity was delayed by 2.5 years,
and the subadult life stage was extended by
1.5 years.

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IGUANA  •  VOLUME 15, NUMBER 2  •  JUNE 2008 119CONSERVATION RESEARCH REPORTS

could have positive repercussions for the
species in Kansas. RIEDLE ET AL. (2008.
Transactions of the Kansas Academy of
Science 111:21–28) outlined current
knowledge of the species in both states,
provided information on management
efforts for the species in Oklahoma, and

made recommendations for interstate
collaboration for managing the species in
Kansas.

Ranching to Conserve 
Horsfield’s Tortoises

According to CITES, ranching is a
method based on the collection of eggs,
incubation, and artificial hatching. Since
1997, associates of Zoocomplex
(Tashkent, Uzbekistan) have studied
hatching of Horsfield’s Tortoises
(Agrionemys horsfieldii) on farms at com-
mercial levels. BYKOVA ET AL. (2007.
Russian Journal of Herpetology 14:
232–236) obtained 20,000 eggs from
tortoises kept in captivity, those tem-
porarily kept in the nursery, and collected
in the wild. Egg lengths varied from
36.1–56.5 mm. Survival rate of eggs was

75%. Body sizes of hatched tortoises
were positively correlated with egg sizes.
The size of hatched tortoises was
25.2–48.6 mm and about 20 g. During
seven months of rearing, 5% of hatched
tortoises died (versus 70–90% in the
wild). Of 15,000 hatched tortoises, 29
twins (13 normal and 16 pairs asymmet-
rical) and four terato-twin abnormalities
with varying levels of terato-duplication
were recorded.

Conservation Status of the 
Ecuadorian Snake Dipsas andiana

While studying the distribution and nat-
ural history of Dipsas andiana, a little-
known snake endemic to Ecuador,
CISNEROS-HEREDIA (2007. Russian
Journal of Herpetology 14:199–202)
determined that the conservation status
of D. andiana would classify for the
IUCN category “Near Threatened”
(NT). The ecological distribution of the
species is apparently related with seasonal
forests of the West Ecuadorian zone, a
recently recognized biogeographic region
between the very humid Choco and the
dry Tumbesian zone.

Management efforts for Alligator Snapping
Turtles (Macrochelys temminckii) in
Oklahoma could have positive repercussions
for the species in Kansas.

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Ranching Horsfield’s Tortoises (Agrionemys horsfieldii) in Russia has been successful and may
provide a hedge against extinction in nature.

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Dipsas andiana, a little-known dipsadid
snake endemic to Ecuador, is associated with
seasonal forests of the West Ecuadorian zone. 

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Serpents and Dragons: Finding the Beauty in the Beast
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The photo book, Serpents and Dragons: Finding the Beauty in the
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information about the book and how to purchase it can be found on
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