I have previously blogged about our adult male Blanding's turtle, Skip, and the problems that Blanding's turtles face here in Massachusetts. I have also blogged about the head-start program for Northern red-bellied turtles. Combining those two themes together, today's blog is about the head-start program for Blanding's turtles.


Head-started Blanding's turtles

Blanding's turtle nests are protected with wire cages at several locations in Massachusetts. When the babies hatch in the fall they are sent to several institutions to be raised through the winter. By the following spring, they are large enough to improve their chance of survival, and are released back to the swamps where they were collected.

It isn't possible to determine the gender of baby turtles from the outside, but medical technology is now allowing us to look inside their bodies to determine whether they have testes or ovaries. These images are from a recent procedure we did to check the gender of ten head-started Blanding's turtles. The turtles will be released in a month or so.



The turtles are put under anesthesia, and a small incision is made in front of the hind leg to allow the scope to be introduced into the body cavity. The gonad is located along the front surface of the kidney.



In this image, the testicle is the light tan, smooth, elongated structure in the center of the image. It is only a few millimeters in size, but the scope magnifies it so that we can see it better.

We found that all of the babies were male! The gender of Blanding's turtles, like many turtle species, is determined by the incubation temperature of the egg. If the eggs in a nest were all at about the same temperature, all of the babies will be the same sex. For Blanding's, cooler temperatures produce males. So it is likely that the babies that we examined came from relatively cool nests. The biologists that study these turtles will be looking into this in more detail this summer. We are planning to check some more babies soon, and we are hoping to find some females.

We thank the many individuals and institutions that are working on this project in addition to the New England Aquarium: Zoo New England, Hyla Ecological, Oxbow Associates, Mass Wildlife, and U.S. Fish and Wildlife.

-Dr. Innis

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Labels: Blanding's, gender, head start, laporoscopy

This post is not about sea turtles, but it's about northern red-bellied cooters. This is a type of freshwater turtle that lives in the Eastern United States, including New Jersey, Pennsylvania, Delaware, Maryland, and Virginia. Interestingly, there is also a population of this species that lives in Plymouth County, MA, several hundred miles away from any other known populations.

It used to be thought that Plymouth red-bellied turtles were a separate species, but DNA testing has shown that they are the same species as those that live in other states. However, the Plymouth population is unique enough to be considered as a genetically distinct population. In the 1980's the numbers of red-bellied turtles in Massachusetts was very low, only about 200 - 300 animals, so they were placed on the United States and Massachusetts Endangered Species List.


In order to increase the number of red-bellied turtles in Massachusetts, scientists started a project called a "head-start" program. In the wild, many turtle eggs are eaten by animals such as raccoons and skunks. To prevent this, scientists began putting wire cages over red-bellied turtle nests so that the eggs would not be eaten. When the baby turtles hatch in the fall, some of them are brought to institutions like the New England Aquarium, and they are raised over the winter.


This way, the turtles grow large enough so that they will not be eaten by fish, crows, frogs, etc. Over the past twenty years, the head-start program has increased the population of red-bellied turtles in Massachusetts up to 2000 - 3000 animals! In fact, some head-started turtles have now become old enough to lay eggs of their own.





We thank the many individuals and organizations that have helped red-bellied turtles over the years, especially Terry Graham, Tom French, and Dave Taylor, and the late Allison Haskell. We will keep you updated on the progress of these babies, which will be released to the wild later this spring.

- Dr. Innis

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Labels: Bill Murphy, freshwater turtles, head start, Red-bellied cooters