Week 1: Modeling and Canoeing

I began my summer research on June 3rd, returning to the Quantitative Biology Lab tucked in a back corner of the ISC’s second floor.  Unlike most of the other biology and chemistry labs on this floor, here you won’t find any vials full of chemicals, Bunsen burners, or lab mice.  Instead, it’s a lab full of computers where we design mathematical models, and couches where we gather for group discussions.  I spent most of my research hours this week in the lab, making adjustments to the diamondback terrapin population model that I was working on during the past school year.

Many of the modifications were minor, but I also worked with my advisor to make some bigger changes, like adding in variables for mate choice.  Male terrapins can mate with either immature females, which produce about 10 eggs per year, or mature females, which produce 20-30.  The new variables will allow us to examine what effect any degree of male preference for one stage versus the other would have on the future population size.

While not having any chemicals means we get to wear flip-flops and have food in our lab, I do enjoy the more hands-on aspects of biology.  So, I was very excited to head out to Queens Lake on Wednesday with Professor LaMar and Professor Chambers to scope out locations to place traps for the terrapins.  I got a few bites from greenhead flies while walking along the dock over the marsh, but the weather couldn’t have been more perfect.  The sun was out and there was enough of a breeze to keep us cool.

The dock we launched the canoe from is on the property of a family that has a summer house on the water, and they’ve been nice enough to let us trek across their backyard every weekday this summer.  Professor Chambers and I used the canoe to examine the creeks branching off into the marsh, and chose spots for ten traps.  The spots have to be at just the right depth; low enough so the traps won’t be completely exposed at low tide, but high enough that the chimneys will be above the water at high tide, so the terrapins can come up for air.

We saw a couple terrapins that day.  They’re difficult to spot; all you can see is a little head just above the surface of the water.  We also saw some blue herons, fish, and a water snake.  The plan was to return on Friday to place the traps, but the tropical storm kept us inside all day.

Beginning Week 2, we’ll start going out to the water every day to check the traps.  We’ll measure the terrapins in the traps, and record their age and sex.  We’ll then mark their shells so we can tell if we catch the same ones more than once, and release them.  Hopefully then I’ll have some good pictures to post!

– Sarah Gilliand