A fool-proof plan for rodents?

We’re still showing off the Young N’ Wild of the U.S. Fish and Wildlife Service. This week’s guest blogger is Brian Merewitz, who worked on a project at the Service’s Chesapeake Bay Field Office to study how small mammals may be affected by changes in their habitat. 

As a little kid, I always wanted a pet hamster, but my parents never let me have one.  Luckily, after my sophomore year of college I finally got my chance to play with rodents.  In my second summer at the U.S. Fish and Wildlife Service Chesapeake Bay Field Office, I was asked to design and conduct my own research project.

That’s me! I led a project to investigate how small mammal populations are affected by habitat change at the Service’s Chesapeake Bay Field Office in Annapolis, Md.

A white-footed mouse, one of the small mammals I studied as a part of this project.

After speaking with my supervisors, I decided to measure small mammal population dynamics on two separate man-made islands and then compare the results.  This data would allow us to see how the small mammal populations change as island habitats mature and plant communities change.  So, I went ahead and did my research and wrote an elaborate plan that sounded like a little kid’s dream.  I was going to trap small mammals, mark them, and then recapture them—on an island.  Finally, after research and rounds of revisions– yes, my teachers were right that papers need to be revised–I had a fool-proof plan that would work just as I hoped.  Now it was time for the fun to begin.

One of the trap boxes.

It didn’t take long for me to realize that I was a little naive.  My “fool-proof” plan wasn’t as simple in the field as it seemed on paper.  First of all, I had to set up a grid with traps every 10 meters, which any college undergraduate should surely be able to do.  Well, it was a little tougher than I imagined because for some reason there were shrubs that were really inconvenient.  Being on an island meant that I had to actually remember to bring everything I needed with me.  I brought the GIS map that had every latitude/longitude for each trap and I had the GPS, but it didn’t take long to figure out that the points weren’t right.  Luckily my supervisor had a compass and 100 meter tape in the work shed, so we improvised and got it set up.  Bottom line—setting up took longer than I had hoped, but we finally got all the traps and bait set, so now I could finally get to play with rodents!

Still, the complications didn’t stop.  Apparently, not only do rodents like peanut butter, oats, carrots, and meal worms, but so do snakes and ants.

Peanut butter does indeed track more insects and animals than just rodents.

I am no rodent expert, so identifying squirming mice-looking things is harder than I anticipated.  At first, we were marking them by coloring their ears black with a permanent marker, but after one session of that, we realized it was hard to identify, so from here on, small mammals got green nail polish.  Oh, and tides change, so traps that are on the shore one day, may be gone the next.  After these complications, I did actually get data and run statistics and present my findings.

Through this summer, I learned that nothing goes as planned, biologists do a lot of planning for each project, and that if I ever need to scare my supervisor, I just need to bring in a mouse!