As some of you know, I am involved in Blanding's Turtle Conservation. Last fall we began what I hope will be a long term survivorship study of turtles that we have been headstarting and releasing. We release somewhere in the region of 200 young turtles per year but we really have no idea if any of them are actually surviving, hence the need for the study. Our headstarted turtles are two years old when we release them, at that age they are about four or five inches long. In order to track them we have to equip them with a radio transmitter. Because they are so small the transmitter has to be tiny in order not to hinder their movement at all and because the transmitters are so tiny, so are the batteries that power them. These batteries last for approximately six to seven months. We release the young turtles in October, they go into hibernation, usually until late March, early April and then we begin tracking them. Of course with the winter we have had, everything is running a little late this year and so it was late April before we could get out to track them and then we are up against the end of the battery time for the transmitters.
Anyway, we finally got out. The weather was great even if the water was still frigid! But hey that is when neoprene chest waders really become your best friend. 'We' consists of yours truly and my two partners in crime, Jamie and Dan.
We met up bright and early at an 'undisclosed location' (one of the plethora of protocols involved with working with an endangered species is not discussing specific site locations) and waded off into the marsh to begin searching for radio signals transmitted from the young turtles we released last year.
It is always good to start the day on a positive note and we were very fortunate that the first few individuals we tracked were found alive and well.
Each individual was thoroughly checked over for injuries and the GPS location it was found at recorded.
One of the reasons that this project was started in the first place was because when the Blanding's turtle habitats were surveyed there was a reasonably steady population of adult turtles that would appear annually but there was never any hatchlings, juveniles or sub-adults found and it became very apparent that they were falling victim to increasingly heavy predation. So we knew that we were not going to only find fit healthy turtles. The first casualty of the day that we found was something of a mystery because it appeared as if this little turtle had literally died five minutes ago.
It had no marks on it that suggested a predator attack, it was in water and yet showed no signs (or smell) of decay and its transmitter was still intact and signalling strongly. We kept it to conduct a necropsy but I suspect we will never know what happened to that one.
More common casualties were victims of predation, the primary culprits being raccoons and mink. Sometimes we found a twisted and chewed transmitter, minus the turtle
And sometimes we found a twisted and chewed transmitter attached to a shell, minus the turtle! Which is always a very sad moment but, of course inevitable.
In amongst tracking the young turtles we checked in on some of our resident females who were also just coming out of hibernation. We will be monitoring them over the coming weeks and when they are found to be gravid we will put them into laying pens so that they can lay their eggs without fear of predation.
All the females that we found seemed to have come through the long hard winter in good health which is always positive news as they provide us with future generations.
In amongst tracking the Blanding's Turtles we did happen upon a good size Snapping Turtle and I just couldn't resist checking him/her out!
Now in case you are wondering, for those of you not familiar with this species, there is a very good reason why these turtles are so named and with an individual of this size there is really only one really safe way to pick them up if you value your fingers!!!
With most turtles you can hold the edges of the shell between the front and back legs quite safely. Lets just say the Snapping Turtles have extremely long necks................
Having returned the snapper to his basking spot and kept all ten of my digits we returned to the business in hand and continued tracking the young hatchlings.
We had a great day, nine hours out in the sun wading about in a marsh isn't a bad days work and from initial findings we seem to be currently getting a forty percent survival rate for our newly liberated turtles which is a huge improvement on zero percent.
Our next task will be tracking the survivors again and equipping them with new radio transmitters to last them through the summer.
Photo Credits - J. Forberg & CJT
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