Managing Fish Habitat

February 4, 2009 by admin

By Doug Leier

We’re heading into that time of year when the majority of our outdoors thoughts turn toward fishing. The bulk of the snow geese are well beyond North Dakota. The excitement of the first couple of weekends for spring turkey are past, and those of us who applied for a bighorn sheep, moose or elk license have learned of our fate in the lottery drawing.

And so, much of the conversation relates to the passion people have for getting outdoors and enjoying the stellar fishing North Dakota provides. It’s also a good time to reflect on the factors that contribute to those opportunities.

Contrary to what many believe, North Dakota fishing has more than just Devils Lake or the Missouri River System. While the state isn’t blessed with abundant deep, natural lakes, it has its share of quality fisheries. From McGregor Dam to Mooreton Pond, and Bowman-Haley Dam to Homme Dam, anglers in North Dakota are seldom more than a few casts away from not just wetting a line, but putting fillets in the frying pan.

A lot of this has to do with habitat.

Habitat is not just a duck, deer and pheasant issue. Fish have the same requirements for food, water, shelter and space as do birds and mammals.

Without sufficient water, of course, fish can’t survive in the long term. North Dakota is a state whose water fortunes are greatly influence by climatic wet and dry cycles. The state experienced a historic wet cycle from 1993 through about 2000. For awhile, just about every fishing lake in the state took on new water that led to an expanding fishery.

Since then, much of the state has been on the dry side. While some smaller lakes and reservoirs retained much of that extra water, others have now lost enough water so that their fisheries either no longer exist, or are greatly reduced.

Nature’s cycles also influence larger waters like Devils Lake and Lake Sakakawea. These large bodies of water are North Dakota’s two most popular fishing destinations. They are only about 100 miles apart, but provide extreme examples of how weather cycles don’t exactly coincide within state boundaries.

Starting in summer 1993, the water level in Devils Lake started rising. Vegetation was flooded and provided a multitude of benefits for fish species and the fishery as a whole. Newly flooded vegetation provided nutrients for fish, substrate for natural reproduction and also cover for young fish to escape from predators.

While the rising water created many headaches for humans, it was and still is a boon for the fishery.

On the other side of the spectrum is Lake Sakakawea, which also rose dramatically in the summer of 1993 and then topped off in 1997. The overall fishery expanded as well.

Since then, steadily declining water levels created more competition for food, reduced space, and the fishery subsequently began to decline. Fishing remained good from the standpoint of catching fish, but a reduced forage base has meant slow growth of fish in recent years.

To complicate matters, at its current level Sakakawea contains little adequate spawning habitat for walleyes or northern pike, so there has been little natural reproduction of late.

Unlike some of the boom-and-bust prairie lakes, Sakakawea will never be in danger of losing its ability to support fish life. It has plenty of water for that, and it’s still a good place to catch walleye and northern pike.

It’s those other variables – the food, shelter and space – that influence how many fish the lake can produce.

I could write thousands of words on the twists and turns that have shaped North Dakota’s two most popular fishing destinations, even without including anything on the time and money spent just to maintain angler and boater access to the water. Across the state similar conditions are working their way through smaller lakes and reservoirs and a reduced scale.

As you spend time casting at your favorite fishing hole this spring, take a minute and reflect on how important those other habitat components are, no matter the size of the water.