DTWG Objectives:•Advocate and promote scientific surveys/studies; identify causes of changes to populations•Identify threats to populations•Maintain database of populations studied•Provide advice/recommendations for research, management, and conservationSlides Prepared by Dr. Russ Burke, Dr. John Wnek and Ms. Kim Belfer
Nesting Ecology Activity
Egg, hatchling and juvenile
Activity developed through the Marine Academy of
Technology and Environmental Science in Manahawkin.
New Jersey. Produced through students in “Project
Terrapin” with the generous support of the following
Terrapin Egg and Juvenile Survivorship Activity
Diamondback Terrapin Egg and Juvenile Survivorship Activity
Introduction for the Educator (100 egg activity)
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.
Female terrapins grow larger than males and some females could be as large as 23 cm (9
inches) in carapace length. Males are smaller and may reach sizes of 15 – 18 cm (6 or 7
inches) as adults. In terms of maturation, females in New Jersey can mature in 7 – 9
years, while males can mature in 3 – 5 years. Females will nest on bay beach areas
adjacent to marshes where they can deposit up to 18 eggs (called a clutch of eggs). The
mean clutch size at Sedge Island, Barnegat Bay, New Jersey is around 12 eggs (Wnek,
2006 and 2007). The nesting female terrapin will dig a nest, deposit eggs and
immediately return to the water. The depth of the nest depends on the compaction of soil
and depth at which the female can dig. Eggs are d