Wednesday, September 12, 2012

A Familiar Face

I find it hard to believe that it's already the second week of September, which means that Michigan's impending doom if quickly approaching. The trees in the northern part of the state are just starting to levitate towards their autumn colors and the daylight hours continue to shorten. This time of year is the beginning of a max exodus of reptiles & amphibians back to their respective hibernation sites and can lead to very productive days in the field. I'm hoping in the next few weeks an afternoon of cruising will produce a hognose snake or two, along with a few other species. I had an hour or two to kill on a Tuesday afternoon so I decided to take a walk along a northern Michigan river in hopes of seeing some wood turtles moving back from their summer haunts towards the river corridor will they will be hibernating over the course of the winter. While walking through the shallow water, I noticed movement ahead of me near the bank. One wood turtle emerged from the river and was quickly followed by another. They appeared to be two males, one chasing the other. The runner quickly looped back towards the river and disappeared, but the big male decided to rest on the bank and was easily apprehended for a few photos.

Wood Turtle - Glyptemys insculpta

Wood turtles are a striking species, especially when an individual displays as much yellow on the carapace as this big guy. This particular male is one I've seen before, the last time being in November of 2010. He's one of two males in this stretch of the river that are considerably older and larger than the others, and he seems to patrol up and down at least a 400-500 yards of the river corridor.

Same male in Nobember 2010

After radio tracking this species for the past two summers in New Jersey, I've been able to gain a much better understanding of movement patterns and home ranges between males and females. Females seem to wander far greater distances from the stream corridor than males do, especially during nesting season. They also typically spend much of their summer away from the stream in woodlands, pastures, and fields where they forage on mushrooms, slugs, worms, and berries. Males do wander out of the river, but they never seem to move far away from the river itself, usually remaining within one hundred yards of the river itself. However, they move far distances up and down the corridor where they search for mates or other competing males. It's interesting seeing these patterns, even without telemetry. When I saw this male in 2010, he was at least 300 yards further upstream than he was when I found him on this particular afternoon. It was nice to see a familiar face and wish this big fella all the best in the coming winter months.

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