Description
The Spiny Softshell is distinctive in being our only
freshwater turtle with a flexible, leathery carapace. It is a large turtle
reaching up
to 54 cm carapace length
although males
are only half this size. The carapace is
rough and has small spiny projections at the front edge. It is
olive to tan with dark blotches. The plastron is hingeless and white
or yellow.
The snout is distinctively tubular.
Confusing Species
With its soft, leathery carapace, the Spiny Softshell
cannot be
easily confused with any other species in Canada.
Distribution
The distribution in Canada is limited to southwestern
Quebec and southwestern Ontario. It is widely distributed in the
eastern United States as far south as Texas and into Mexico. There
are some disjunct populations in the west.
Habitat
Spiny Softshells are generally found in rivers with
soft bottoms, aquatic vegetation and sandbars or mudflats. They
are occasionally found in lakes or impoundments.
Reproduction
Females may take more than 10 years to mature in
Canada. Mating occurs in spring, usually in deep water. Nesting
occurs in June and July in sandy areas. Females produce two
clutches of eggs each year in the southern US, although they may
only nest once in Canada. Up to 39 eggs are laid, although the
usual number is less than half that. Unlike most species of
turtles, the sex of hatchlings is independent of incubation
temperature. Eggs hatch in late summer or fall and the young are
3-4 cm long.
Natural history
Spiny Softshells are mainly aquatic, although they do
frequently bask along the banks of streams. Individuals will bask
communally. They are aggressive when threatened and should not be
handled. Females may even squirt blood from their eyes when
handled. They feed primarily on insects, fish and crayfish but may
eat vegetation. Spiny Softshells can get almost half their oxygen
by breathing through their skin while underwater. Some individuals
will move up to 30 km along a stream over the course of a summer.
Spiny Softshells can live for over 25 years.
Conservation Concerns
Spiny Softshells have historically been collected for
food and their numbers have been reduced. Some are also
accidentally caught on fish hooks. Great care must be taken
to remove them from the hooks without harm to either the turtle or
the fisher. They are currently designated Threatened in Canada by
COSEWIC.
|