Alnitak
Member
- Joined
- Jan 6, 2014
- Messages
- 314
Yesterday my brother-in-law and I took a nostalgia trip to Laurel Run in Perry County. There's two--I'm referring to the one in Tuscarora State Forest, near Landisburg. We used to fish for brook trout there back in the early 1990's. I moved away from the area for grad school, then life happened, and its been 21 years since either of us were last there. My brother-in-law had heard that the trout were practically wiped out by acid rain. I wanted to go back and see what was going on, as the stream is still listed by PFBC as having wild brook trout reproduction.
I know that the stream was stocked until sometime in the late 1980's, but that stocking had ceased for a variety of reasons, including acid deposition via acid rain. Laurel Run is a beautiful wild freestone stream, but it has very limited buffering capacity so it was highly susceptible to acid rain.
We fished about 0.75 of stream upstream from where Elk Hill Road crosses the stream in Tuscarora State Forest. In the years we fished the stream, we never caught anything but brook trout. Consequently, I was surprised when the first fish I caught was a small 6" wild brown trout. After that we proceeded to catch mostly brook trout and chubs. Between the two of us, we landed about a dozen brook trout in five hours of fishing--not a lot, but not bad given that the water was a bit high and running fast. There were mayfly, caddisfly and stonefly larvae in the stream and we saw a few mayflies and caddis flies hatching. The brook trout all looked healthy and most ranged from 6-9" in length. My brother-in-law hooked into one that was a bit larger, but wasn't able to bring it to the net. As the evening ended I caught another little wild brown trout, not quite 5" long.
I was fascinated by this for a couple of reasons. First, brown trout are less tolerant of lower pH values than brookies. Second, seeing any brown trout here at all was a surprise. They must be coming from Shermans Creek, although its not listed as having a wild brown trout population. I spent several hours last night and this morning doing some research on both Laurel Run and acid rain deposition more broadly, and found some interesting tidbits.
It appears that Laurel Run had some limestone put in one of the branches upstream from where we fished about 10-15 years ago. However, even with that addition, a research project conducted by a student at Bucknell in 2004 found that the pH outside of that stretch was too low, and the dissolved Aluminum levels too high to support brook trout. While some trout no doubt persisted, clearly it was tough going for them. Finding acid rain data was not easy, but I finally managed to track down information from the EPA from some of PA's monitoring sites, and lo and behold, the environmental regulations are working. The average pH at the Perry County site was last updated two years ago, but at that time the average pH was 5, up considerably from the average of 4.4 in 2004. At a pH of 5 brook trout and brown trout can survive. The Millersville site shows a trend to where pH is now averaging nearly 5.6; if Perry County has similarly continued to increase I can see why the browns can now breed there.
Anyway...we often chat here about the return of wild trout to many PA streams, and I see temperature and runoff cited as key reasons--but we should add a reduction in acid deposition as another factor, particularly for freestoners. This is all great proof that sensible environmental regulations have broad positive impact.
Jeff
I know that the stream was stocked until sometime in the late 1980's, but that stocking had ceased for a variety of reasons, including acid deposition via acid rain. Laurel Run is a beautiful wild freestone stream, but it has very limited buffering capacity so it was highly susceptible to acid rain.
We fished about 0.75 of stream upstream from where Elk Hill Road crosses the stream in Tuscarora State Forest. In the years we fished the stream, we never caught anything but brook trout. Consequently, I was surprised when the first fish I caught was a small 6" wild brown trout. After that we proceeded to catch mostly brook trout and chubs. Between the two of us, we landed about a dozen brook trout in five hours of fishing--not a lot, but not bad given that the water was a bit high and running fast. There were mayfly, caddisfly and stonefly larvae in the stream and we saw a few mayflies and caddis flies hatching. The brook trout all looked healthy and most ranged from 6-9" in length. My brother-in-law hooked into one that was a bit larger, but wasn't able to bring it to the net. As the evening ended I caught another little wild brown trout, not quite 5" long.
I was fascinated by this for a couple of reasons. First, brown trout are less tolerant of lower pH values than brookies. Second, seeing any brown trout here at all was a surprise. They must be coming from Shermans Creek, although its not listed as having a wild brown trout population. I spent several hours last night and this morning doing some research on both Laurel Run and acid rain deposition more broadly, and found some interesting tidbits.
It appears that Laurel Run had some limestone put in one of the branches upstream from where we fished about 10-15 years ago. However, even with that addition, a research project conducted by a student at Bucknell in 2004 found that the pH outside of that stretch was too low, and the dissolved Aluminum levels too high to support brook trout. While some trout no doubt persisted, clearly it was tough going for them. Finding acid rain data was not easy, but I finally managed to track down information from the EPA from some of PA's monitoring sites, and lo and behold, the environmental regulations are working. The average pH at the Perry County site was last updated two years ago, but at that time the average pH was 5, up considerably from the average of 4.4 in 2004. At a pH of 5 brook trout and brown trout can survive. The Millersville site shows a trend to where pH is now averaging nearly 5.6; if Perry County has similarly continued to increase I can see why the browns can now breed there.
Anyway...we often chat here about the return of wild trout to many PA streams, and I see temperature and runoff cited as key reasons--but we should add a reduction in acid deposition as another factor, particularly for freestoners. This is all great proof that sensible environmental regulations have broad positive impact.
Jeff
