Description
Blanding's Turtles have an elongated smooth black carapace with irregular tan or
yellow
markings. These markings may be absent or fade in some
individuals. The chin and throat are bright yellow. The plastron is hinged
and either yellow with a large dark blotch in the corner of each scute or almost entirely black.
Adults reach
up to 28 cm carapace length.
Confusing Species
No other Canadian species has the bright yellow chin
and throat. Map Turtles have
yellowing
marking on the carapace but
also have
yellow lines on the neck and legs and the rear of their carapace is serrated. Spotted Turtles have distinct yellow
spots
rather than irregular markings.
Distribution
In Canada, Blanding's Turtles are found in southern
Ontario and a few localities in western Quebec. There is a
disjunct population in Nova Scotia. Blanding's Turtle is limited
mainly to the Great Lakes region of the United States as far west
as Nebraska. There are disjunct populations along the Atlantic
coast as far south as New York.
Habitat
Blanding's Turtles live in highly productive lakes,
ponds and wetlands with clean shallow water and mucky bottoms.
Reproduction
Females do not mature until at least age 14. Nesting
occurs in late May to early June and up to 22 eggs are laid in a
single clutch. Nests are dug in areas of well drained sandy loam
or sand. Hatchlings emerge in the fall at 3-4 cm in length. The
gender of offspring depends on the incubation temperature of the
eggs.
Natural history
Blanding's Turtles are fond of basking, particularly in
the spring. Crayfish are a favourite food but insects, fish, frogs
and plants are also eaten. When disturbed, Blanding's Turtles can
pull in and move the lobes of their plastron to close the shell. The
pattern on
the carapace appears to
imitate Duckweed,
thus providing camouflage for the turtle. Blanding's Turtles
commonly live more than 25 years and possibly over 70 years.
Conservation Concerns
Blanding's Turtles are vulnerable to traffic mortality
and high nest predation. The Nova Scotia population is designated
as Threatened by COSEWIC.
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