Reprinted from Fly Fishing Quarterly
Many Maine fly fishermen abandon trout ponds in midsummer because they feel high water temperatures make trout sluggish and difficult to catch. I do just the opposite. I increase my efforts during this time of year, because in many ponds, almost all the fish can be found in the vicinity of a few cold-water sources called springholes. With the trout concentrated, the angler who knows how to find and fish these places has a great advantage.
Trout are cold-blooded creatures whose optimum body temperature is between 48° and 62°F. Water temperatures above 70° cause their activity levels to decline dramatically; prolonged exposure to temperatures in excess of 72° causes them to die. This is why shallow ponds that lack an external cold-water source are unable to support a trout population throughout the summer. Spring-fed ponds, however, are continually in fused with cold (usually around 50°) water from underground. When the weather turns hot, trout naturally migrate to these areas.
Finding Springholes
Just because trout can find these cold water refuges doesn’t mean that you always can. Fortunately, a few basic rules can help make the job a little easier.
First, try to restrict your efforts to ponds that are 15 acres or less in size. Then utilize biological survey information (provided by most state fish and game departments) to help you determine which ponds contain healthy populations of trout.
Second, follow an organized plan for finding the springholes. I like to begin by visually surveying the bottom while wearing polarized glasses. This works best on calm, bright days. If the water is shallow and clear, you can often see places that are lighter in color than the rest of the bottom. They’re areas where silt and mud have been removed from the bottom gravel by the continual movement of fish congregating in the pocket of cold water.
Rising fish are another reliable indicator. When no fish are showing, you can use other clues, like the localized activity of aquatic insects, the position of other fishermen, and even the flight activity of insect-eating birds. Narrowing of the search area is a key to finding springholes consistently.
The final step in locating springholes is to verify (with a thermometer) that the water temperature in the vicinity of a suspected springhole as actually colder than the rest of the pond. The type of thermometer you choose is a matter of budget and convenience. Since I do a lot of springhole fishing, I invested in an electronic Clinefinder that has a probe that can quickly provide a temperature reading from any depth. A simple thermometer on a string can do the same thing, but you have to wait 30 seconds or so for the information. The point is, be sure to verify the location of your springholes before spending the day casting over a piece fishless 75F water.
Record the location of each springhole that you discover. I always draw a map that includes the boat-launch area and three or four other easily identifiable reference points on the shore. A waypoint marked on your GPS is also essential. The point is, never trust your memory alone.
When fishing, I also like to set out temporary markers in ponds with multiple springholes. I frequently use plastic bobbers anchored to the bottom with a heavy sinker or rock. Then I can travel back and forth among them without having to painstakingly re-establish their exact location every time I move my boat. Always retrieve all your markers at the end of the day.
Tactics and Flies
Don’t lose sight of the fact that trout congregate around springholes because it’s uncomfortable for them to remain elsewhere in the pond. Also remember that being confined to such a small area often causes their behavior (feeding, etc.) to become somewhat erratic and unpredictable. At certain times, springhole trout will bite like crazy, and at other times, it’s tough to get them to bite at all. Even the best springhole fishermen must occasionally wait-out these periods of inactivity.
You can do some things to increase your overall rate of success. First, avoid fishing shallow (three feet or less) springholes on bright days. When the sun is on the water, fish seem to get spooky and abandon these places, especially in ponds that receive a significant amount of angling pressure. I usually fish these areas only very early in the morning or on overcast and rainy days.
Next, be open-minded in your selection of flies. Frequently, a pattern that works great one day won’t draw a strike the next. To get a quick fix on what might be productive at the moment, I quickly work through a variety of patterns until I find something that interests the fish. Then I stick with that pattern until the action dies.
Don’t leave home without a handful of basic patterns. These include Woolly Buggers tied in a variety of sizes and colors (olive, black, and brown), scuds, small casting streamers, and soft hackled, impressionist nymphs, like the the Hare’s Ear and Timberline Emerger. By no means are these the only flies that will work. In fact, my list of favorite springhole patterns is constantly changing. Lately, my two most productive flies have been a brown marabou Muddler and a Maple Syrup Nymph.
Techniques
Of equal importance to fly selection is being willing to experiment with a variety of retrieves. Springhole trout can be finicky about the amount of movement they’ll respond to. So I experiment with retrieves that range from a painstakingly slow hand-twist crawl, to an erratic, fast strip, until I find one that works. Generally, the slow, steady retrieves are more effective, but you just never know.
One aspect of springhole fishing that isn’t as unpredictable is fly presentation. After locating a springhole, it’s important to position your boat so you can cast your fly 10 to 15 feet beyond the intended target. Then, let your line sink to a position just off the bottom before beginning your retrieve. This allows your fly to pass through the entire pocket of cold water and usually produces the best results.
Wherever spooking trout is a consideration (shallow springholes or ponds with crystal-clear water), keep your boat as far away from the fish as possible. Here, long casts (up to 60 feet) are important. In deeper water, you can usually safely anchor your boat within 25 feet of a springhole, provided you’re quiet.
The key to a good presentation in these deeper areas is to shake out an extra 10 to 15 feet of line onto the water immediately after you complete the cast. This allows the line to sink to the bottom evenly and the fly to be retrieved in a semi-horizontal position. Strikes can occur any time after you begin the retrieve. Many trout seem to strike near the boat when the fly begins to move up from the bottom.
Setting anchors from both the bow and stem can significantly improve your springhole fishing success. Two anchors not only prevent your boat from whipping around in the wind, but they also significantly reduces the chance of your line being disturbed while counting down, and of boat shadows being cast across the fish-holding area. A properly oriented, stationary boat is particularly important when two anglers are fishing together because it can provide both with a direct casting lane to the target.
More important than mastering all of these technical skills, however, is to accept the fact that you won’t become a successful springhole fisherman overnight. Too many anglers start out with great intentions, but get impatient and give up before they really experience how good this type of fishing can be. Those who stick it out are rewarded with a wealth of summertime fishing opportunities that other anglers only dream about.