LOW WATER ANGLING
Most of the country has been experiencing an extended period of hot and dry conditions. In the Northern Rockies we experienced a warmer and dryer than normal winter followed by a dry spring and a hot and dry summer. This combination has resulted in most many lakes and streams being at or below record lows.
There are several relevant points to consider when thinking about the impact of low water on resident fish populations. For the angler, these low flows present both an opportunity and a challenge. Low flows concentrate the fish in the deeper pools and at or near the mouth of tributary streams that may be discharging cooler water. In lakes and other stillwaters the fish may be concentrated in deeper water and areas where springs may be discharging cooler oxygenated water. When an angler finds these areas it may result in excellent angling opportunities, however, the fish are concentrated in these areas for survival purposes. The question for the angler is whether or not to attempt to catch fish under these conditions.
Warm water holds less oxygen making it more difficult for the fish to breath, and low water levels allow temperatures to increase faster than when the water is deeper. A fish that is hooked by an angler must expend energy in an attempt to escape and this struggle increases the need for more oxygen. In warmer water a hooked fish must work harder to get enough oxygen to maintain life and if the struggle lasts too long they may die even though the angler releases them. Fortunately, with the coming of fall and the shorter days and cooler nights, especially across the northern tier of states, the water temperatures are declining helping to eliminate the danger of low oxygen levels in most waters.
Although cooler nights and shorter days are helping lower the water temperatures, streams and lakes are still experiencing low water. Less water means that the fish are concentrated more closely than normal, and this adds to the stress they experience. Concentrated populations of fish are also more susceptible to predation and this also increases the stress level the fish are suffering.
One tool that may be helpful during low water periods is a stream thermometer. This will allow you to determine the actual temperature of the water where you are planning to fish. Water temperatures in excess of 70 degrees Fahrenheit for cold water fish like trout are beginning to border on the extreme. If you encounter temperatures in excess of 75 degrees Fahrenheit you should seriously consider doing something else until the water temperatures cool down.
Anglers that desire to fish under these conditions and still wish to be respectful of the resource should follow a few simple rules to help insure that any long term impact on the fishery will be negligible.
First, try to fish when the water is at its lowest temperature for the day. This will normally occur early in the morning. On overcast days the water temperature may remain cool for most of the day, and that will allow for longer angling time. On days when it's bright and sunny anglers should limit their time on the water to those cooler hours of early morning.
Secondly, use heavier tippets and land the fish quickly. Using light tippets that require the angler to play the fish longer should be avoided. Once you have hooked a fish land it as quickly as possible to avoid exhausting the fish to the point where it cannot recover. To facilitate easy release uses barbless hooks or pinch down the barbs on your regular hooks.
Thirdly, when landing a fish under these conditions do not take it out of the water. Using a net will help eliminate the need to play the fish long enough to allow it to be landed by hand, and will also eliminate the need to remove it from the water. Keep the fish in the water, remove the hook, and allow the fish to rest in the net until it is ready to swim away. If the fish is exhausted so that it cannot remain upright in the net it may be necessary to hold the fish in the current or move the fish around so that water flows over its gills. If you want to photograph your catch take the picture while it's in the net and still in the water.
Finally, limit the number of fish that you catch. When you find a pool where the fish are concentrated limit the number of fish that you hook in that pool, since hooking and releasing fish under low water conditions increases the stress that they are already experiencing. Think quality and not quantity when fishing under extreme conditions.
While fishing under low water conditions limits angling opportunities, with a little bit of caution it's still possible to enjoy a day of fly fishing. Be considerate of the resource and we all will enjoy continuing angling opportunities for years to come.