THE STEINHART AQUARIUM - Gulf of Guinea Science ...

208 A Docent Field Guide to the Species of the Steinhart Aquarium
can sell for over $50, as it is believed to have
aphrodisiac properties.
When caught, this tortoise emits high-pitched
cries, sometimes lasting an hour after capture.
This noise would startle a predator in the wild,
an effective defense.
Pancake Tortoise
Malacochersus tornieri (Testudinidae)
Distribution: Confined to Kenya and Tanzania
and a small population recently reported in
Zambia.
Habitat: Lives among rocky outcroppings in
dry areas of scrub brush.
Appearance: Unlike most tortoises, the pancake
tortoise sports a soft, flexible shell rather than a
rigid, thick one. Its common name reflects its flatas-a-pancake
profile. Length: 6–7 inches (15–18
cm); height: 2 inches (5 cm).
Diet: Grasses and other vegetation, including
red oat grass and aloe. Also eats seeds and
nuts. During the dry season, the diet provides
sufficient moisture.
Reproduction and Development: Mating
occurs in January, egg laying and nesting in
July and August. The female generally lays a
single egg per clutch and several clutches may
be laid per year.
Mortality/Longevity: Because of the soft shell,
this tortoise is easy to tear apart though not
so easy to catch, an evolutionary tradeoff that
seems in the natural predator-prey cycle to
favor the tortoise. Mongooses and predatory
birds are among its predators
Remarks: Its flat and flexible shell allows it to
shelter in narrow crevices. Once tightly lodged in
its cranny, the tortoise then braces its legs against
the rock. These maneuvers usually thwart
even the most determined predator’s efforts to
dislodge it. They live communally, with several
tortoises peaceably sharing a crevice.
Because of its light shell, the animal is the
fastest tortoise known and depends on
escaping danger by dashing for the nearest
crevice hideout rather than by withdrawing
into its shell. Its relative lightness and agility
also enable it to flip over quickly if turned on its
back, an advantage for an animal that spends
most of its day climbing over and perhaps
falling from steep. rock-strewn hills.
Spider Tortoise aka Madagascar Spider Tortoise
Pyxis arachnoides (Testudinidae)
Tortoises
Distribution: Southwestern Madagascar.
Habitat: Dry deciduous forest.
Appearance: Highly variable among subspecies.
Diet: Opportunistic browsers.
Reproduction and Development: Sexual
maturity at ~12 years; clutch size 1 egg.
Conservation Status: IUCN: Critically
Endangered because of habitat loss and its
popularity in the pet trade due to its small size
and the handsome design on its carapace. Low
reproductive rate exacerbates these pressures.
Will likely be extinct in the wild in less than 30
years; global climatic change not included in
that dire conclusion.
ORDER CROCODYLIA
American Alligator
Alligator mississippiensis (Crocodylidae)
Distribution: Southeastern United States, from
North Carolina to the Rio Grande in Texas. The
wetlands it inhabits frequently overlap with
human-populated areas.
Habitat: Usually found in freshwater, especially
in slow-moving rivers. They are also found in
swamps, marshes, and lakes. They can tolerate
salt water only briefly.
Appearance: Average female length is 2.6
m; average male length is 3.4 m. The largest
recorded male was 5.8 m long. Exceptionally
large males can weigh over 450 kg. Alligators
have between 74 and 80 teeth, which are replaced
as they wear down; an alligator can go through
2,000 to 3,000 teeth in a lifetime. The tail, which
accounts for half of the alligator’s total length,
is primarily used for aquatic propulsion, but is
also an effective defensive weapon.
Diet: Alligators eat almost anything, but
primarily consume fish, birds, turtles, mammals
and amphibians. Hatchlings mostly eat
invertebrates. Once an alligator reaches adulthood,
it will prey on any animal that lives in the
water or comes there to drink. Adult alligators
will eat domestic animals including cattle, and
will also kill and eat smaller alligators. Larger
males have been known to tackle Florida
panthers and bears, making the alligator the
apex predator throughout its distribution.