Excerpted from: Animal Diversity
||6 to 10 inches
||Dark colored carapace with yellow dots and stripes.
||10 to 26 eggs
||Crustaceans, fish eggs, fish, frogs, snails and vegetation
The smooth carapace of Blanding’s turtles ranges from dark brown to black.
These ectothermic reptiles have yellow spots on their dorsal shells. As adults,
their plastrons have a variety of black and yellow patterns, the most common
being yellow with black spots along the scutes. The shells of adult turtles can
stretch from 6-10 inches. Weights range from 1.5-3 pounds. Their heads are
flat and the dorsal and sides are bluish-gray. Their eyes protrude, while their
snouts do not. Yellow scales can be seen on the legs and tails and they have
webbed toes. Although there are no significant size differences between male
and female Blanding’s turtles, male plastrons are usually more concave than
those of females.
The minimum expected lifespan of wild Blanding’s turtles is 70 years, while the
maximum is 77 years. There are no known captive breeding programs, so
information on the lifespan of captive Blanding’s turtles is not available. There
has been confounding studies on whether male or female turtles live longer.
However, studies have shown that there is an overall positive correlation between
the age of Blanding’s turtles and survivorship. The annual survivorship of male
and female adults (14+ years of age) is over 93%, while that of juveniles (1-13
years of age) is around 72%
Although Blanding’s turtles are mostly aquatic, they commonly emerge from the
water to rest on logs, sedge clumps, or any terrestrial land that is close to their
aquatic homes. These turtles will usually move when searching for habitats that
are plentiful with food, mate accessible and also when the females are finding a
good spot to nest. Beginning in mid-April and continuing through mid-July, there
is hardly any traveling among these turtles.
Turtles that inhabit the larger lakes will stay in their same locations for tens of years.
Seasonal wetland inhabitants will change location and travel greater distances
compared to the turtles occupying the lakes. Juvenile Blanding’s turtles also travel
in their search for an aquatic habitat when they are first hatched, looking to find an
adequate overwintering spot to lessen their chances of freezing to death. On land,
males will travel more, found to on average travel over 10 km. Females however,
only travel over 2 km, not including the nesting period of the females, where they
can reach up to 7.5 km in travel. These turtles will travel between 1 to 230 meters
daily in water.
During October and November, these reptiles will begin overwintering
as a group, staying mostly in ponds, and they will hibernate until the end of March.
Following their period of hibernation, they will begin breeding. Blanding’s turtles
that are located in the more southern regions of their geographic range can withstand
colder temperatures and will stay active in ambient temperatures as cold as 35 degrees F.
During the mating season, male Blanding’s turtles rely on their tactile senses. Mounting
is one of these tactile activities, as is gulping. In the latter activity, the males sway their
bodies and spew water from their mouths onto the females’ head.
Blanding’s turtles are omnivores, but half of their diet consists of crustaceans, including
crayfish. These reptiles will consume their food alive, or as carrion. They also eat insects
and other invertebrates. These turtles resort to aquatic insects such as dragonfly nymphs
and aquatic beetles when crayfish are not available in certain geographic locations. Blanding’s
turtles also will consume fish eggs, fish, frogs, and snails. They will eat coontail, duckweed,
sedge, and bulrush as well, and will also eat seeds. The adult turtles are more carnivorous,
with up to over 75% of the diet being meat, while the juvenile Blanding’s turtles eat more plants.
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