Fishing success dependent on stocking in many waters
Inevitably, when fishing expectations aren't met in lakes and reservoirs across the state, anglers wonder why. It could be anything from anglers simply using the wrong bait, to an unhealthy fish population because of any number of factors such as...
Inevitably, when fishing expectations aren't met in lakes and reservoirs across the state, anglers wonder why.
It could be anything from anglers simply using the wrong bait, to an unhealthy fish population because of any number of factors such as low water levels, poor water quality, introduced aquatic nuisance species and others. When such situations occur, the first response often is a call to the Game and Fish Department to stock more fish.
On the surface, stocking can seem like an easy solution. A lake lacks fish, you just put more fish in and two or three years later, the problem is resolved. When you look under the surface, however, the solution is seldom that simple.
That said, stocking does have its place, and the North Dakota Game and Fish Department directs considerable resources to producing and stocking fish.
Jerry Weigel, supervisor for fisheries production and development for the Game and Fish Department, describes the North Dakota philosophy on stocking fish: "We stock lakes in North Dakota that many other states probably wouldn't take a second look at."
In other words, Game and Fish biologists work hard to provide the best possible opportunities given the hand they were dealt. Since North Dakota does not have nearly the number of natural, deep fishing waters as its eastern neighbors, stocking often plays a major role in developing or maintaining opportunities that otherwise would not exist.
In natural lakes and rivers, certain kinds of fish have been present for ages. They have evolved, so they can reproduce within the type of habitat the water provides and have adapted to certain food sources.
Reservoirs or lakes created when rivers or creeks are impounded may provide livable water for fish, but they may not have the type of spawning habitat that allows certain kinds of fish to reproduce.
What has been observed during high water years is that natural reproduction can occur even in some of our smaller water bodies. But during normal or dry conditions, natural reproduction often is limited, so stocking may be necessary to sustain a fishery in the long term.
Reservoir water levels also change more dramatically than natural waters. What might be good spawning habitat one year could be several feet from the water's edge the following year. If water levels fall far enough, a reservoir may not be able to support fish life over the winter.
As Weigel points out, "In times of extended drought, our challenge is to maintain a solid base of fishing opportunity."
On the other hand, high water levels can stimulate a fishery resurgence. Flooded vegetation, which is ideal spawning habitat for northern pike and yellow perch, also is a hideout for small fish of other desirable species such as walleye or bass. In the last decade, we've seen this high-water phenomenon influence dozens of lakes -- both natural and man-made -- across the state.
Now that North Dakota has experienced several dry years, especially in the western two-thirds of the state, reservoir water levels are falling. In many cases, even in large bodies of water such as Devils Lake and Sakakawea, occasional stocking serves as sort of a safety net, helping to smooth out the peaks and valleys that would otherwise occur naturally during periods of drought or abundant moisture.
For example, for the past two years Game and Fish has stocked about 1 million yellow perch fingerling annually into Devils Lake. These fish are marked, so they can be differentiated from naturally reproduced fish. Results indicate that natural reproduction contributes many more perch to Devils Lake than these intensive stocking efforts.
Water management on reservoirs also is important. Big reservoirs, such as Pipestem near Jamestown, N.D., or Lake Ashtabula north of Valley City, N.D., are managed more for flood control, making a quality fishery more dependent on stocking.
In comparison, most Minnesota lakes remain relatively stable because they are not subject to annual increased or reduced flows to maintain flood protection.
Is it working?
Each year, Game and Fish biologists net certain waters to survey year-class recruitment, a method of determining stocking or natural reproduction effectiveness. "Through our data collection, we are better able to see if our stocking efforts are making the grade," Weigel said. "In many reservoirs, stocking is a must due to limited natural reproduction, while in some larger bodies of water it's not as essential."
The bottom line is good fishing is a relative term for each individual angler, and stocking is one of the tools used to put fish on the end of the line for many North Dakota anglers.
Doug Leier is a biologist with the North Dakota Game and Fish Department in West Fargo. Read his blog daily at www.areavoices .