Yellow-spotted Side-necked Turtle
(Podocnemis unifilis )
Classification
and Range
Turtles
and tortoises make up the order Chelonia. Side-necked turtles (suborder
Pleurodira) are found only on the island of Madagascar and continents of
Africa, Australia and South America. Most of the turtles we are familiar
with are more closely related to each other than to side-necked turtles.
Yellow-spotted side-necked turtles belong to the family Pelomedusidae,
one of two families which make up the suborder of side-necked turtles.
Yellow-spotted
side-necked turtles (Podocnemis unifilis) are found throughout
the Amazon and Orinoco drainages.
Habitat
They usually are found in the tributaries of larger rivers. During the flood
season, they avoid fast-moving waters by taking up residence in lakes and
in flooded forests.
Length
and Weight
A turtle's "length" is expressed as the length of its shell from front
to back in a straight line, not measured over the curve of the top of the shell.
The largest yellow-spotted side-necked turtles are females, and the maximum length
for a female is about 18 inches (45 cm). Females at Woodland Park Zoo are slightly
smaller than the record length and weigh about 14 pounds (6.5 kg). Males weigh
about 5-6 pounds (2.5-2.8 kg).
Life
Span
Up to (approximately) 70 years
Diet
In the wild: Mainly vegetable matter, grasses,
fruits and leaves, but also carrion (dead fish and animals) and
mollusks
At
the zoo: Greens and fruits, “"raptor diet" (a
ground meat diet intended for birds of prey), and "turtle
jello" which contains fish and generous amounts of vitamins
and minerals.
Reproduction
A male yellow-spotted side-necked turtle courts
a larger female by nipping at her feet and tail. He then swims above
her and curls his relatively longer tail around the edge of her shell.
His copulatory organ emerges from his cloaca and introduces semen into
the cloaca of the female.
A few weeks later, under cover of darkness, the female lays about two dozen hard-shelled,
slightly-elongated eggs in a nest she has dug on the riverbank. The babies, which
are slightly larger than a 25-cent piece, hatch out in a little over two months.
Life Cycle
A few days after hatching, the baby turtles begin looking
for food on their own, while trying to stay away from the many animals
who prey on very small turtles: birds, snakes, large fish and frogs,
and even many kinds of mammals. The baby turtles have very obvious
yellow spots on their heads, which become reduced as they grow. Males
keep some of the yellow spotting; females lose their spots altogether.
Side-necked: What's
That All About?
Most of the familiar kinds of turtles, members of the suborder
Cryptodira, protect themselves from danger by pulling their heads
and necks back into their shells by curving their cervical spine
(the bones of the neck) into an "S" in
a vertical plane. You'd be able to see that's if you X-rayed
a turtle from the side. A side-necked turtle is so-called because it does not
pull its head and neck directly back into its shell; instead, it tucks its
head and neck under the edge (the margin) of the shell to one side, curving
its neck in a horizontal plane.
Location
at the Zoo
Yellow-spotted side-necked turtles are on exhibit
in two locations at Woodland Park Zoo: a number of immature turtles
can be seen in one of the aquatic exhibits in the Tropical Rain Forest.
A group of approximately 24 adults and juveniles inhabits the large
turtle pool in the Day Exhibit, where this species has lived for
more than 25 years and where more than 70 babies have been produced
since 1985. Other turtle species that can be seen in the Day Exhibit
are the Egyptian tortoise, redfoot tortoise and the Indian star tortoise.
Conservation Connection
Although the yellow-spotted side-necked turtle is
an internationally protected endangered species, it is also an important
food resource for the people who live in Amazonia, who harvest eggs
and hunt the turtles for their meat. The Brazilian government, however,
has undertaken an ambitious protection program. Armed guards are
used to protect the important nesting sites of this and other hunted
turtle species. This allows the turtles to nest safely and the eggs
to hatch without human interference. As a result of this successful
program, hundreds of thousands of these endangered turtles are expected
to hatch in these protected areas each year and disperse into the
waterways of the Amazon river system.
How You Can Help!
The effort to save endangered species like the yellow-spotted side-necked
turtle requires cooperation and support at the international, national,
regional and individual levels. You can help in this cause. Join
and become active in Woodland Park Zoo and other conservation organizations
of your choice. Don't buy products made from wild animal
parts. Don't buy wild-caught turtles and other animals for
pets. Contact your elected representatives and express your views
about conservation of endangered species and wild habitats.
Contact Woodland Park Zoo at webkeeper@zoo.org to
find out other ways you can support conservation programs at the
zoo. Discover more about turtles by contacting the Society for
the Study of Amphibians and Reptiles at 303 W. 39th St., PO Box
626, Hays, KS 67601. Learn other ways you can help conserve wildlife
and the habitats they require for survival by visiting our How You Can Help page.
Reptiles as Pets
We do not recommend reptiles as pets for most people as they require very specialized diets and environments. We also receive hundreds of requests each year to take former pet iguanas, boas and other reptiles but we cannot accept these due to space, health and unknown backgrounds. If you need to find a reptile or amphibian a new home, we suggest you contact a local herpetological group in your area. In the Puget Sound region, contact the Pacific Northwest Herpetological Society as a resource. If you do choose to get a reptile as a pet, please learn as much as possible about their care and the best species before making your decision and never accept wild-caught animals as pets or release non-native reptiles or amphibians into the wild.
Sources and Suggested Reading
Alderton, David. 1988. Turtles & Tortoises of the World. Facts
on File, New York, NY. 191 p.
Harless & Morlock, eds. 1979. Turtles, Perspectives & Research. John
Wiley & Sons, New York, NY. 695 p.
Pritchard, Peter C. H. 1979. Encyclopedia of Turtles. TFH Publications, Neptune,
NJ. 895 p.
Pritchard & Trebbau. 1984. Turtles of Venezuela. Society for the Study
of Reptiles and Amphibians. Oxford, OH. 403 p.
For Kids!
Matero, Robert. 1993. Reptiles. Kidsbooks, Inc., Chicago,
IL. 29 p.
Zoobooks. 1993. Turtles. Wildlife Education, Ltd., San Diego, CA. 18 p.