Abnormal Amphibian Survey

Continuing my work at the Bear River Migratory Bird Refuge, I was given an assignment that I never thought I would be conducting at a bird refuge: frog catching. Katie, one of my supervisors here at the refuge, explained the project to me as a large sampling of frogs across the country, mainly the Northern Leopard frog and the Western Chorus frog here at the refuge. This information will be used to determine the abnormalities of frogs in our area compared to frogs in other areas of the country. The presence of a high proportion of abnormalities in our population would suggest contamination of our water in some way.

So, my mission, as I had to accept it, was to catch these little buggers. This seemed like an easy enough mission, given that much of my childhood was spent in the creeks of southern Ohio doing just that. However, as I soon found out, these frogs are far different than the ones jumping  around my childhood back woods. The first few days spent on this mission turned out hardly any results, as Nikki and I were looking for tadpoles of the species, and the only real way to do this is dip your net into the water randomly and hope for the best. Luck has never really been on my side, and I like a challenge in my work opposed to blind luck.

After a good four hours of walking all over the BRMBR wetlands without any frogs to show one day, we realized why the tadpoles escaped us- we spotted the tiniest frog hoping around on the grass next to us.  They had already begun to meta-morph into terrestrial beings, and we were simply looking in the wrong place. The next day, we went back to a pond in which many tadpoles were caught at weeks before, and sure enough, frog soup. I caught 20 Northern leopard frogs just by myself that day, using a technique I had to develop as we went along. They float motionless in the water, and you can’t see their little eyes staring up at you. Like a ninja, one must creep slowly in the water towards them without any sudden movement, until your net is within striking distance. Then, like a flash of lightning, come down upon the frog and scoop it towards you to ensure that it won't escape. This, of course, works for the Northern Leopard frogs. The Chorus on the other hand is the size of a dime and was only caught by looking at the dry ground and spotting them in between cracks.

All caught frogs were then put into ziplock baggies, brought into the lap, and then numbered and measured for a different array of things, such as SVL (snout to vent length) and Gosner stage, as well was carefully examined for any abnormalities. All abnormalities were sent in to headquarters, along with a frog quota from each site.

For more information on the project, visit http://www.fws.gov/contaminants/Issues/Amphibians.cfm



Catching frogs in the field

Measuring and Accessing each frog

Science

 Our subjects in waiting
 My supervisors investigating an abnormality
After a hard days work

Examining frogs in the lab.