What constitutes an exceptional brook trout stream or rather, what criteria is needed to make an exceptional brook trout stream ? I have an idea of some that are present and necessary in all of the streams that I would consider exceptional brookie streams. They are not absolute but from my experience, the more of them that are present, the greater the fishery whether we are talking brookies or other species like brown trout. Also, by no means does my list encompass all of them… So lets discuss some of them. First I need to give you a back story.
Pennsylvania is blessed with an unbelievable amount of quality trout water. It is largely due to its geology and vast parts of the state that remain forested and undeveloped. It has more trout water than any other state except Alaska. I believe Alaska only beats Pennsylvania because of its shear size. Someday I feel Pennsylvania will be distinguished as being number 1. There are literally too many blue lines and listed waters to possibly fish in a life time but I’m gonna try my best !
My friend Rowan of Connecticut Fly Angler Blog and I went to PA for a few days to meet another friend of mine and fish Spring Creek and some other water as well. Our intentions were to fish the Tricos on Spring but as luck would have it, Spring Creek as well as everywhere else was running high and off-color from the historic amounts of rain Central and most of Eastern Pennsylvania received this summer. We were unfortunate in February as well with high water and flooding conditions. Neither of us were complaining about it since that is what they need on a steady basis to keep the aquifers full. To give you an idea as how well they will be for fall conditions and spawning, Penns Creek was a cool 62-64 degrees in August. I don’t think the trout in Penns felt that kind of water temp in the summer for a long time !
Anyway, back to the story. We passed this blue line in February while traveling to State College. Rowan was passing the time while I drove by looking on google maps for information on it. There wasn’t much but it looked like it ran for a long distance. I have past this stream many times before but never stopped to look or bother with it. It peaked out curiosity this past February but at that time, we weren’t in the mood for exploring after fishing in flooding water and being rained on all trip. However, this trip we had great weather and the time to check it out on our way home. Boy are we glad we did because it turned out to be a highlight of the trip ! For one, Rowan caught another species on his bucket list and we discovered an exceptional brook trout fishery.
This leads me to what I consider as some of the necessary criteria needed to create and maintain an exceptional brookie stream.
First, you need old growth as pictured below.

Older forests provide stable soils for streams and are less likely to be eroded and silted out from high water or floods. Also, they provide coolness to the forest and keep the brook shaded so that it doesn’t warm up too much. If the brook is spring fed then it will remain in the 50’s like the one we fished ( 58 degrees ). If the stream is marginal, then older forest growth and shade will help minimize rapid temperature spikes and hopefully keep the temps in a trout friendly range during the summer months. Older forest are largely undisturbed which means that they are in areas not populated by people so man’s encroachment with development is at a minimum. Paved roads and sub developments are killers to any waterway regardless of type or how many ” barriers ” are placed to offset developed lands- you simply can not replace mother nature’s ability to care for fragile ecosystems !
Second, you generally need a stream or brook that runs for great distances.

This particular stream runs for a long distance ! I don’t want to give up anything too revealing even though it is out-of-state. Myself and other blue line fishermen go to great lengths to avoid showing revealing pictures or give up too many identifying features. Anyway, streams that run for a significant length offers brookies many opportunities to find suitable habitat for feeding, safety and spawning. In addition, streams or brooks that run for long distance have to ability to disperse the fishes genetics enough so that they are able survive and thrive. Long flowing brooks means they are probably undisturbed so they won’t have drainage culverts and other development features that impose on the fishery, too. If there happens to be other species in the brook, i.e. brown or rainbow trout, then a long flowing brook helps brookies survive the added pressure and dangers. Long flowing brooks have a greater potential at picking up cooled ground water and springs to keep it at brookie friendly temperatures as well.
Third, exceptional brookie streams have a good population of old and mature fish.
This is an exceptional brookie. I didn’t measure it but you can tell that it is a big mature fish. Only exceptional brookie streams that remain exceptional have these kinds of brookies in them. Rowan and I caught several in a very short period of time and in a very short section that we explored. Older mature fish pass on the needed genetics that are necessary for the species to survive. Older mature fish are better at spawning and passing on the genetic strain. In addition, finding large and mature brookies probably means that man has not disturbed the fishery that much ( over fishing, harvesting and poaching ).
Fourth, exceptional brookie streams do not have missing classes of fish.
Not missing any classes of fish means that the stream ecology is stable enough to provide the necessary habitat for a success spawn year after year. You can see that this is a smaller and younger brookie. Rowan and I caught and released several year classes in just a few hours.
Fifth, exceptional brookie streams have fish in them that live a long time.

This brookie still has par markings and is rather chunky and good length. The brookies in this stream most definitely has a strong and stable population. I personally haven’t seen a brookie of this size in Connecticut still with par marking and be that large. Again, a great testament to the fact that in this particular fishery, the brookies generally live out their full expectancy life span.
Sixth, exceptional brookie streams offer a tremendous amount of added protection in-stream and on the banks.
Here Rowan is faced with trying to fish a deep pool that has cover and concealment on the banks from all sides as well as in-stream wood debris for added cover. Exceptional brookie streams have plenty of in-stream structures and deep enough pools to survive cold winters, shelf ice, and protection from woodland creatures like raccoons, bears, birds, snakes, mink, muskrat, not to mention crazed blue line fly fishers !
Finally, should the stream experience some fishing pressure, exceptional brookie streams make it very difficult to fish.

Exceptional brookie streams don’t make it easy for just anyone to fish them ! I have found that most brookie streams that are rated as good to exceptional are also the most difficult to fish, particularly with a fly rod . I like to think that they also deter the vast majority of fisherman from them as a result. Besides, most are in areas that require lots of walking, wearing bug spray, sweating, and expending a great amount of time and energy to fish and explore properly.
This is an ultimate test to one’s ability to cast a fly rod in tight brush. First, you can’t get too close or you will possibly spook every brookie in the pool. Second, you have to approach it from below so you have a lip to overcome and a narrow chute. Third, you have little to no casting freedom from either side and overhanging cover, too. Finally, what is not shown in the picture is that you also don’t have any casting freedom behind you and you can not false cast either. I think most fly fishers would shy away from this stuff ! Good, I’m glad. I am just as greedy and secretive as any other blue line affection ado !
So…the brook trout is threatened in many places throughout its native range but not this particular stream!
Connecticut does have a few streams that are close to exceptional and remain very secret and guarded. However, most are poor to decent with some good ones mixed in terms of brook trout populations. Hopefully with continued conservation and reestablishment efforts, I and other blue line nuts will be able to continue to fish for our beloved brookies for a long time to come and perhaps even gain some more ” exceptional brookie streams ” in our own state ! But, I will still try my best to fish all of Pennsylvania too !
As always, I hope to see some of you out there at some point and be a good steward of the environment and pick up trash, release fish quickly and safely, monitor water temperatures and inform the DEEP should you find something wrong. And, join your local Trout Unlimited chapter or local conservation group. We at Thames Valley TU ( Chapter 282 – my chapter ) will gladly welcome more members.