Big Fish, Tiny Stream

Deep valleys dissecting a flat plateau

I made two trips west to fish this weekend. On Saturday I was kept off the water by thunderstorms, but on Sunday the weather stayed relatively clear. Thanks to the recent rains, the first stream I tried was very stained. I decided to drive upstream to the headwaters in search of clearer waters.

The stream was tiny in most places...

Near the top of the valley I crossed a small tributary. It wasn't on my map of classified trout streams, but it was somewhat clear and the pool near the bridge looked deep. I fished the bridge pool first, but caught nothing but a few small chubs.

...except for under the bridge

I moved downstream and realized the stream was tiny - below the bridge pool it was just 1-2 feet wide in most places. I didn't catch any fish in the few small pools I found here, so I decided to try the big pool one more time before leaving.

This time I tried to cast a bit farther under the bridge. I let my small wooly bugger sink for a few seconds then began slowly pulling it in. I felt a tug much stronger than one from a chub, and soon pulled in an extremely light-colored brook trout.

Almost colorless

Emboldened by my success, I decided to try again. A few casts later, I felt an even strong tug. A nice wild brown put up a great fight, at one point jumping a couple feet out of the water.

I kept going, and soon found the best fish of all. Unlike the previous brown, this one never came near the surface. It stayed deep and pulled hard, putting up a strong fight against my 2 weight. Luckily he had nowhere to go in the small pool, so I was able to net him. I don't know exactly how big he was, but I would estimate somewhere in the 14-16" range and very fat with a bit of a kype. Easy my personal best wild brown.

Though a great fish anywhere, it was even better catching it out of such a tiny stream.

A Few Nice Small Stream Trout

I haven’t had a lot of opportunities to fish recently, mainly due to time spent recovering from Lyme disease (check for ticks!). I did get out in the rain for a few hours last week though, and the fish were cooperating.

I started fishing at a pool just upstream of the road. I usually fish this pool first, and I almost always get a hit. This is mainly a brook trout stream, but there are a few browns around, especially in this section. I let a small wooly bugger drift downstream, and just as it passed under some overhanging branches I saw a wake and felt a strong tug. The fight was tough in such close quarters, but I was able to land this beautiful 10” brown.

Later I met up with Geoff, and we started working downstream as the rain began to fall. We found a few small brookies, but the action was slow, so we decided to drive downstream to a different access point.

Near the head of a now-drained mill pond a nice brook trout slammed my foam hopper. Geoff got this short gif of the release:

We decided to bushwhack upstream through some nearly impassable terrain, an area in which the stream completely disappears under bushes for several stretches. After working our way through the swamp we found ourselves at a small beaver pond. Geoff skittered a caddis across the surface and it was quickly smashed by a beautiful 10” brookie.

Beaver pond brookie

After that we called it a day, satisfied having caught some nice-sized fish.

Wild Brookies and Browns in Western MA

Yesterday I took a trip to one of my favorite streams. It originates in the hills to the west of the Quabbin reservoir before eventually working its way down to the Connecticut river. This stream holds both wild brook and brown trout, including some large specimens of each, and is stocked in the lower sections.

I started out in a meandering meadow stretch full of woody debris and deep pools. I decided to start out with an Elk Hair Caddis, which produced as usual. As I moved upstream I caught small brookies and browns in nearly every pool.

Can you spot the trout?

One of the best spots of the day was this pool below a small beaver dam. I saw some fish rising, so I worked my way out to a gravel bar just downstream to make a cast. I pulled 3 or 4 brookies out before the action stopped.

The Beaver Pool

Later I moved downstream to an area dominated by wild browns. The water in this stretch was low for this time of year, but it was still cold. In the first big pool I saw some rises, but I was using a wooly bugger. I decided to cast the bugger to them anyway, and I got a take. I landed this stocked brookie pretty easily - probably because he only had half a tail!

A little bit farther upstream there's a deep channel underneath a footbridge. I found this nice wild brown there and he put up the best fight of the day.

Yellow Rockets

Yesterday afternoon I got over to Wisconsin for the first time in about a month. It was a gray day, but Yellow Rocket was in full bloom along the streams and fields. Though it's a troublesome weed for farmers, I was happy to see a splash of color added to the landscape.

Fortunately those weren't the only yellow rockets I found yesterday. The wild browns were out in force.

At the first stream there were occasional rises, but nothing consistent, so I decided to try a small streamer. I worked my way downstream through a stretch of TU Habitat Improvement and started picking up fish right away. The TU work created some riffles in a stretch that was previously flat and shallow. In the first riffle I got a nice brook trout that got off before I could get a picture, but a little further downstream I redeemed myself with this brown.

I got another brookie and a few more small browns before reaching the end of the habitat improvement. Downstream there are plenty of fish, but the stream is shallow, flat, and choked with brush - not the most fun place to fish. I decided to head down to the larger river into which this stream feeds.

I realized immediately upon reaching the water that I made a good decision - fish were rising everywhere and I could see caddis skimming the surface. I found a nice, unoccupied stretch of river (this spot can get crowded), tied on an Elk Hair Caddis, and got to work. It wasn't long before I had my first take. The fish weren't rising consistently, but I found that I could usually get a strike if I put my fly over the fish a couple seconds after a rise to a natural.

I caught 3 and had many more strikes before I decided to call it a day. Glad to finally get back into some trout!

Geology and the Trout Stream

The other day I was talking with Will from Flies, Fat Tires, and Family about a small wild trout stream we both fish. We both noticed that the fish there are bigger and more numerous than in similar streams, and Will mentioned that a friend from the MA Division of Fisheries and Wildlife told him electroshocking confirmed these observations.

A nice brook trout from the stream in question

A quick look at the Massachusetts Coldwater Fishery Resource List will tell you that there are a lot of wild trout streams in Massachusetts - over 1,200, in fact. But not all 1,200 have fish like the stream Will and I like. You might think that the best streams are those with the most pristine watersheds, but that isn't always true. This stream is fairly close to Boston, yet it is far more productive than several streams I've fished further west.

So why is this stream so much better? The answer is, at least in part, geology.

Bedrock and Acid Rain

Bedrock is the layer of rock that lies underneath soil, sand, and other deposits on the surface. If you've explored the White Mountains of New Hampshire, you've probably seen the granite bedrock jutting out from the thin mountain soil.

So how does bedrock affect a trout stream? Groundwater, which contributes a significant portion of the flow of most wild trout streams, flows over and through bedrock on its way to the stream. As it flows, it dissolves some of the rock, changing the chemical content of the water. For trout, the most important consequence of this chemical change is acidity.

Different trout species have different tolerances to acidity, with Brook Trout being the most tolerant and Rainbow Trout the least. But the direct effects of acidity on the trout are not the most significant influence on productivity, rather it is the effects on their food supply that translate to the quality of the stream. Most aquatic insects prefer water in the neutral to slightly basic range (pH ~7-8), and crustaceans, such as scuds and sowbugs, require basic conditions to prevent their shells from dissolving. This means that all other things being equal, a more basic trout stream will have more food, and therefore more/bigger trout than an acidic stream.

Precipitation is naturally mildly acidic (pH < 7), but in areas with significant industrial pollution (basically all of the Northeast and Great Lakes) it can be significantly worse. As this precipitation flows into the ground, the acid is neutralized by basic ions dissolved from the rock. The only problem is, when it comes to neutralizing acid, not all rocks are created equal.

Granite, which makes up most of the bedrock in New England, has very little capacity to buffer acid, so our streams tend to be more acidic, and therefore less fertile. The White Mountains are a perfect example - the fish are small and almost all wild fish are brook trout, rather than the less acid-tolerant browns and rainbows. A good counter-example would be the streams of the Driftless area of Wisconsin or the spring creeks of Pennsylvania - the bedrock there is limestone, which has an exceptionally high buffering capacity. This results in highly fertile streams with tons of insects and trout populations exceeding 10,000 fish per mile.

Applying Geology to find a Productive Trout Stream

There are many other types of bedrock besides granite and limestone, each with a different degree of buffering capacity. It can be a little difficult to figure out how a given type of bedrock will influence acidity, so the best things to look for are actual measurements of pH from the stream of interest.

For Massachusetts, a great source of data is the Acid Rain Monitoring Project run by UMass. They have pH data for most streams in the state dating back several decades.

When you look at the data, keep in mind the date of the measurement - nearly every stream will be relatively acidic in late winter and early spring when the snow is melting. Generally, streams with good buffering capacity will run between 6.5 and 8 in summer and fall. If a stream is lower than 6.5 in summer, it's probably somewhat sterile.

If you can't find any pH data for a stream, take a look at a Bedrock Geology map and identify the type of bedrock underlying the stream. Try a Google search for "X bedrock buffering capacity" or "X bedrock acidity". There are an unbelievable number of categories and subcategories of bedrock, so you might not get a definitive answer short of asking a Geologist.

For Massachusetts, the three main types of bedrock with good buffering capacity are Carbonate Rocks (royal blue on the map below), Calcpelite (sky blue), and Calcgranofels (lavender). Find a stream in one of these areas, and the fishing is likely to be pretty good.

Bedrock Geology of Massachusetts - from MA OLIVER

Conclusion

Keep in mind that there are many factors that influence the productivity of a trout stream. A stream flowing over limestone will generally be better than a stream flowing over granite, but there's more to trout fishing than productivity. If granite streams were never fun, no one would fish in the White Mountains, but obviously that's not the case. So as you explore new trout streams this spring, consider geology - just don't forget to consider everything else that makes for a great day on the water!

See also: Aquifers: Saviors of Suburban Trout Streams

A Cool Interview with the Massachusetts Fish and Wildlife Division

While doing some research on trout in Massachusetts I found this cool interview with several members of the Fisheries and Wildlife Division. They go over some of the behind-the-scenes details of trout stocking in the state and spend a good amount of time talking about wild trout, including salters.

Also take some time to check out the blog where I found it: Talkin Trout

Daydreams Fulfilled (Part II)

On Sunday I met up with Aaron to explore some streams in the Pioneer Valley of Western MA. We started out around dawn (after much confusion over DST...) and started working our way west on Routes 2 and 202.

We arrived at the first stream around 8:30 and hit the first large pool. Having caught plenty of fish on Saturday, I told Aaron to take the first pool. I started walking downstream towards another hole, but soon I heard him yell and I turned to see his rod doubled over. As I reached him I saw the fish - a huge holdover rainbow. This stream is lightly stocked, but the last stocking was last spring, so this fish was in the stream for a long time, a fact confirmed by its excellent fin condition and vibrant colors.

We moved upstream a bit, where Aaron hooked and lost what like a small wild brown. I didn't catch anything in this stretch, and we had exhausted the nice pools, so we went back to the car to move upstream.

I've mostly caught wild brookies in the upper section, but some of the browns and stocked rainbows end up there as well. the fishing was slow at first, but soon Aaron hooked into a very big wild brookie in a nice corner pool. As we moved downstream I missed a big strike on a small streamer fished in front of a fallen log.

Aaron's ~12" Brookie (he has huge hands, so it might look smaller)

At one nice pool we spooked a big trout that must have been at least 18" and a few others in the 10-12" range. This stream has some of the biggest fish I've seen for its size. We got to a section with thorny banks and several beaver dams, so we decided to explore a new stream instead of bushwhacking, although there was some nice looking water in this stretch.

Coltsfoot getting ready for an early bloom

The final stream was farther up into the hills on the Eastern end of the Pioneer Valley. Though the hills aren't huge, this stream had characteristics reminiscent of a mountain stream, with large boulders and many solid bedrock ledges. There were also several waterfalls and cascades nearby.

The fishing was slow, but I did manage to get two brookies on a pink squirrel in a pool below one of the falls. At one point we stood next to a very deep pool and watched two brookies feed right below our feet, apparently unbothered by our presence. We tried to get a nymph down to them, but the water was too deep and fast to get a good presentation, so we gave up and started the long drive home.

Daydreams Fulfilled (Part I)

I started this blog as a result of the constant daydreams I had about fishing while stuck inside last winter. With the good weather (at least from a fishing perspective) we've experienced this winter I haven't had nearly as many of these, at least until this week. I was busy over the last few weeks and didn't have any time to get out and fish. I knew the weather was getting nicer, which only led to further frustrations. Every time I let my mind wander, images of deep, clear, flowing waters filled my head.

Fortunately, I was able to get some relief this past weekend.

On Saturday Geoff and I left bright and early for a Salter trip. We were the first car in the parking lot, and quickly made our way to our favorite pool. We didn't get much action at first, but just as I was suggesting to Geoff that we try a new spot, I felt a tug on my line. I turned and quickly pulled in a nice brookie.

Soon after, we ran into Max and his son Nate, who were fishing for Salters for the first time. They seemed pretty thrilled at the couple of big salters we pulled out from under the road while they watched, and they took a few pictures for us. They later told us they were unsuccessful for the day, but this stream can take some time to figure out.

We moved upstream, where we found some smaller, but still fun, brookies hiding out among the watercress and fallen logs.

A beautiful day on Buttermilk Bay

Around mid day, having fished most of the good spots, we decided to hit a small wild brook trout stream in Central MA on the way home.

Looking downstream into the meadow

We saw a ton of stoneflies flying around the stream, so I decided to try a dry, while Geoff stuck with his small streamer. Geoff was the first to pull in a fish, getting two hookups from a pool beneath a culvert. We moved up to a large pool below a small impoundment, and I was able to get my first fish on a dry. It was small, but beautiful nonetheless.

We moved downstream and began seeing occasional rises. We managed to move a fish in nearly every likely spot as we moved through a meadow formed by a drained impoundment and then into a forested ravine. After that we headed home and I geared up for my planned trip the next day.

A Late Report

I've been busy the past couple of weeks and haven't had a chance to post, but here are a few pics from the trips I've taken over that time. It's starting to warm up here, so the fishing should only get better! I'll be back in MA next week, and I'm looking forward to what should be good conditions on some of my favorite streams.