Diamondback terrapins are turtles that inhabit estuaries along the east and Gulf coasts of the United States. They range from Cape Cod, Massachusetts to northern Mexico. Terrapins were harvested in the late 1800’s through the early 1900’s as a food source with a high demand leading to reductions in their populations across their range. In the 1930’s, terrapins became less desirable food sources and populations increased in areas with good habitat, but not much is known about populations in certain areas. What make terrapins so interesting are their markings, which are highly variable and prominent. Reasons for the variation include genetic diversity and some variations in their patterns could be linked to environmental conditions.
<p>DEDICATED TO DIAMONDBACK TERRAPIN
RESEARCH, CONSERVATION, MANAGEMENT
AND EDUCATION
Diamondback Terrapin
Malaclemys terrapin
Diamondback Terrapin
Distribution
• Terrapins inhabit
coastal waters from
Massachusetts to
Texas
• Habitats: salt
marshes & mangrove
swamps
Species Variation
Estuarine Life
History
• Found in brackish water (mix of fresh and salt)
• Sharp bony beak with no teeth for a diet that
includes: snails, fish, mussels, crabs, worms,
algae and other plant material
Habitat: Salt Marsh
Most terrapins live in salt marshes
Habitat: Salt Marsh
Hatchlings moving in a salt marsh
Habitat: Mangrove
Terrapins can also be found in mangrove swamps
Morphology & Physiology
Adapted for water and land:
o Shells streamlined for swimming
o Webbed feet for swimming and nest digging
o Nails for digging into sand or mud
Carapace
Plastron
Feet and Nails
Sexual Dimorphism
MALES
Average length: 6 inches
(15 cm)
Reach sexual maturity at
3 - 7 years old
FEMALES
Average length: 9 inches (23 cm)
Reach sexual maturity at 7 - 11
years old
Adaptations to Saline
Environments
Terrapins "Osmoregulate": regulate % salt in their
bodies
Salt glands in the corner of eyes to secrete salt "tears"
(lachrymal gland)
Example of salt
being extruded
through a salt
gland in a nesting
sea turtle
Brumation
Winter period of reduced activity
Fall
Adults burrow
in the mud
Spring
Mating occurs
In the water
Summer
Females lay
eggs
on land and
return
to water
Overwinters
Hatchlings emerge
in
spring and enter
water
Fall
hatchlings
emerge
Find
wintering
location on
land or
water
Adult
Hatchling
Terrapin Life Cycle: Adult
Fall
Adults burrow in
the mud
Spring
Mating occurs
In the water
Summer
Females lay
eggs
on land and
return
to water
Terrapin Life Cycle: Hatchling
Adult
Hatchling
Overwinters
hatchlings emerge
in spring and enter
the water
Fall
hatchlings
emerge
Find
wintering
location on
land or water
Reproduction
Females can store sperm for years
2 - 22 eggs per clutch (location dependent)
Up to 3 clutc