Friday, January 31, 2014

Rodents in the spotlight!

As I was getting ready to defend my PhD this past July, my advisor got a call from an editor at Smithsonian Magazine with a somewhat strange question. He wanted to know if he could find them some prairie voles to photograph for an upcoming story. He said yes, we have a field site teeming with voles, and since I was the resident wild rodent expert in Bloomington, Keith asked if I might help them. I said as long as they waiting until after the 11th I would be happy to catch some voles in the prospect of working with a real wildlife photographer and to get some publicity for the Indiana University Research and Teaching Preserve.

After a couple phone conversations with John Eastcott, it was planned for him to make the trip from New York state to Bloomington the week after my defence. After months of sitting in front of my computer I was excited to do some field work for fun. I got my field gear all set up and with the help of one of the trusty undergrads in our lab, Tomas, we set up a trapping grid out at Bayles Road, where I did my very first rodent trapping the summer of 2007, just after getting married and before starting my grad studies at IU.

John arrived on the scene in the afternoon while we were setting up the trapping grid. Unfortunately, this week was maybe the hottest and most humid week of the year, and for someone not used to field work during Indiana summer things were more uncomfortable than expected. But John was great, totally professional, and was ready to work. Most of his experience as a wildlife photographer was going to exotic places with his wife, also a journalist, to photograph penguins, elephants, and other charismatic megafauna. In order to get the best shot of these little rodents (prairie voles are about 40 grams, or about 1.5 oz) John constructed a rectangular plexiglass box that could be placed on the ground and could keep the voles in a small space. We scouted some possible locations that would have some good background scenery, give a good sense of the voles habitat. The box would be set up the following morning after the traps were open all night.

The next day, the first day with the animals, was mainly a trouble-shooting day. We had to figure out when the light was just right, and how early we needed to be there to get things ready by this point. Our first try of digging a little trench in the ground for the box to fit into didn’t quite work, we had a couple escapees, and made it so we couldn’t move to follow the light. The box also kept fogging up because it was so humid. We also didn’t get very many animals, which is common when trapping voles; they are usually a little neophobic of the traps the first night and then are more likely to go in the following days. John’s solution was to make a base for the box and then build a little diorama-type scene in it with vegetation dug up from the field site. This ended up looking great, and would allow us to move around the site to find the best places. We set the traps again that night and were ready to go back the following morning.

The next morning we caught a few more voles than the first day. Three of these, a male, female, and juvenile, were all caught in about the same part of the grid which suggests they are part of the same family group. We set up the box, lifted up on some buckets to get a better view of the site and to try and avoid the higher humidity closer to the ground. These guys were the money voles. We started with one of the adults, and John got some great shots of it with the morning sun gleaming over the trees. We then tried putting the other adult in, and they interacted really well together. I then put the juvenile in, and everything was still fine. This suggests to me that either we got a mating pair and one of their offspring, or they were all familiar to each other and maybe used the same nests.
It was really cool to see them behaving in this context because I usually just get them out of a trap and then as soon as I put them back they squiggle through the grass and are gone. They moved through the grass in a way that looks more like swimming than running. Their bodies are long and narrow, kind of like a sausage with short legs. These voles were also very affiliative with each other, cuddling and sniffing. This is where John got the shots used in the magazine.

So after many hours in the hot and humid Indiana weather, crouched behind a blind lying on his stomach, John got the shots he came for. He and the editor described this as a near-impossible task, with how small and elusive these guys can be, but the week was a success!

You can read the related article in the February 2014 issue of Smithsonian Magazine. They have graciously allowed me to link to the story here. The story is mainly about the studies done on why prairie voles are socially monogamous while other vole species are promiscuous or polygynous. There is a lot of interesting work on this, both in the field and in the lab, at many universities. When I worked as a field assistant at Bayles Road it was for a post-doc, Craig Streafeild, in Nancy Solomon’s lab at Miami University-Ohio studying multiple paternity and population genetics of prairie voles in different habitats.

It was a great experience and a neat way to be greeted into the world of experts helping out popular science journalists. Plus, cute vole pictures!

P.S. All the photos I posted here were taken by me, as to not infringe on anyone's copyright. Check out John and Yva's website for more of their awesome photography!


  1. what a great blog entry and good pictures of my John crawling in a grass like a big vole…. thanks, Evie…
    I remember asking you over the phone (I did not come to Indiana because I am a heat wimp) to drag John out and into the nearest shade once his eyeballs start rolling in all this heat, because he will never give up on his own…
    fortunately, you both survived, and so did the voles in love… have a great time in Edinburgh, and we hope our path will cross again -- Yva Momatiuk

  2. Nice! Cool to be behind the scenes! Thanks for taking us virtually!