The following post was created by Devin Beck, a Juniata College senior Environmental Science student. Post edited by Chris Grant.
This being my second summer working in the Grant Lab, I was excited to get back up into the northern woods of PA. I was also excited to start collecting new data for a morphometrics project that is one new aspect of our research on the potential impacts of Marcellus natural gas extraction. A few other students and I will be looking at the morphometrics-or variation in shape-of brook trout in streams with various levels of fracking within their watershed. While I have already started working on the research, we are in its infancy as far as results.
A quick peruse of the literature has turned up very little research done on the effects of pollution or contamination on fish shape. One of the few things that I did find was unpublished research on the morphology of brook trout affected by Abandoned Mine Drainage (AMD) by Dr. Shawn Rummel, of Trout Unlimited. He and collaborators looked at mouth size and body shape in relation to AMD, and found some very interesting results. This study has helped us to develop ideas that we hope to build upon for this project.
On Tuesday we first assessed Little Wolf Creek, which is located in the Allegheny National Forest, just a short walk behind a gated dirt road, near what appears to be an unofficial makeshift shooting range. We caught a number of “brookies and a number of brown trout as well.
The presence of brown trout in this stream is interesting, as they are not a native species. Brown trout were introduced into Pennsylvania in 1886 from parts of Scotland and Germany, and have become a dominant species in many of the streams and areas they were introduced. It has been observed that many streams once only inhabited by wild brook trout are now largely occupied by brown trout. Brown trout can often outcompete native brook trout for food source-helping brown trout to thrive in streams where they co-habitate. Brown trout are also more tolerant of higher temperatures in streams than brook trout are, brook trout can generally survive in water that is up to 20 degrees Celsius, while brown trout can withstand higher temperatures. Last year at Little Wolf only one brown trout and eight brook trout were caught. This year we caught ten brown trout eight of which were young of year (trout that were born this past winter/spring) and only seven adult brook trout. These young brown trout and the size/age distribution of brookies and browns suggest brown trout are reproducing at a faster rate than brookies, meaning more competition and pressure for the brookies in Little Wolf Creek.
After assessing Little Wolf we drove to Bear Creek, located near a state road parking lot where multiple construction vehicles were parked. When we pulled in, one man asked us, “Ya’ll goin fishin or something? What’s with the ghostbusters get-up?” as Allison shouldered the electro-fisher. We laughed, told him a little bit about our project, and then started our short hike to Bear Creek. Once we arrived at the stream, we did the normal run through of data collection including physiochemical stream water measures, stream water methane isotope collection, microbial sampling, periphyton and sediment collection, crayfish hunting, macroinvertebrate kicknet sampling, electrofishing, fish processing, brook trout morphometrics, brook trout blood collection, and brook trout liver collection and fin clips for genomics work. By this point in the summer, everyone had found there groove-and we started to work well as a team towards efficiently collecting data from each site.
Since we were planning on hiking Moccasin and Dutch Hollow the next day, two of our hardest hikes, we decided to end the day at Bear Creek around 6:00PM and head back to the homestead. Everyone went to bed relatively early to rest up and prepare for what what was to come.
It seems crazy to think that the summer is almost half over! Keep checking in for the next post!