Spiny Softshell / Tortue-molle à épines
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 lacks a
hinge and is white or yellow. The snout is distinctively tubular.
With its soft, leathery carapace, the Spiny Softshell
cannot be easily confused with any other species in Canada.
The distribution in Canada is limited to southwestern
Québec 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
Spiny Softshells are generally found in rivers with soft
bottoms, aquatic vegetation and sandbars or mudflats. They are occasionally found in
lakes or impoundments.
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.
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.
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