Anglers see effects of 2011 flood

BISMARCK — As good as fishing has been on the Missouri River and Lake Oahe in the past three of four years, it could be that bad in the coming three or four years. Or more.

Anglers know well the ups and downs of fishing the river and Oahe. In 1997, high water on Lake Sakakawea in North Dakota from record snows in the state led to high releases from Garrison Dam. Often referred to as “the big flush,” millions of rainbow smelt were washed downstream through the Oahe Dam in South Dakota, and it took years for the walleye fishery to recover.

Paul Bailey, fisheries biologist for the North Dakota Game and Fish Department, said the effects of the most recent flooding, in 2011, were evident as the fishing season wore on this past summer.

“Anglers saw firsthand the poor condition of the walleyes,” he said. “We were starting to see the impact of the forage situation on both the river and on Lake Oahe.”

Bailey said the Game and Fish Department does a couple of different surveys of the fish populations on the Missouri River and Lake Oahe each year.

Lake Oahe has three surveys done each year — a spring spawning survey, an adult population survey and a fall production survey in September.

On the river, two electro-shocking surveys are done to track populations, one in the spring and one in the fall.

In 2011, fish on the river and on Oahe were dealt a double-whammy of sorts: cold and windy weather during the spring spawning period followed by record flows on the river during the summer.

“Those two things combined to make 2011 one of our poorest production years,” Bailey said.

After the 1997 “flush” so many smelt were lost to entrainment, the term biologists use to describe fish flushed through dams. Following that event, South Dakota increased daily and possession limits on walleyes because of the lack of a food base below the Oahe Dam.

Even with more liberal limits, there was still a lot of mortality.

Similar measures are being considered now for the South Dakota portion of Lake Oahe, which extends into North Dakota.

Bailey said how good — or bad — fishing will be on the river is dependent on several factors.

On the plus side, smelt are not the only forage source for walleye, northern pike and other game fish. Going back to 2009, which was a phenomenal year for production on the river, there were good numbers of other fish like crappie, white bass, suckers, perch and shiners to go around.

“We do have a diverse forage base on the river,” Bailey said.

But a lot of those fish were lost to last year’s flood.

“This summer a lot of fish were caught,” Bailey said. “Anglers were able to take advantage of what was placed in front of them.”

In other words, there are a lot of hungry fish.

“We’ve never had more mouths to feed than we did in 2011,” he said.

In an effort to restock the cupboards, so to speak, gizzard shad were stocked in Beaver Bay in North Dakota and in seven locations on Lake Oahe in South Dakota.

Gizzard shad found their way into Missouri River waters following 1997 and to some measure, provided an alternative food source in the river and in the reservoir.

Bailey called the stocking efforts this spring a “moderate success.” Some larval gizzard have been found in Beaver Bay and in other areas of Oahe, but because they are not very tolerant to extreme cold, they don’t provide a long-term solution.

The other factors that ultimately dictate how the fish will rebound in the next few years are, by and large, out of the hands of biologists.

With the record releases from last year’s flood, the makeup of the river itself changed dramatically. The river has become more channelized — the sandbars that were around pre-flood have shifted or are gone completely — and tons of sand sediment has been deposited elsewhere.

Many of the shallow side channels and backwater bays that are critical spawning areas for many species are now gone.

“We’ve lost a lot of that habitat,” Bailey said.

Anglers discovered that for themselves over the course of the summer.

A lot of the smaller sandbars that provided current breaks where walleyes lie waiting to ambush forage fish are gone.

The areas that held fish this summer were bigger holes, and it turned into a situation where the small “honey holes” have disappeared and the fish are now relating to bigger community fishing holes.

“It used to be easy to find those current breaks,” Bailey said. “There are fewer places to find fish.”

And, Mother Nature will have a big hand in determining how the river and Lake Oahe will bounce back.

Oahe now is at a low level where boat ramp access is a concern. The main ramp at Beaver Bay is high and dry and if there is much more of a drop, ramps at Cattail and Langoliers bays will be questionable.

The Army Corps of Engineers said last week it could well be another drier-than-normal winter with less-than-average snowfall in the Rocky Mountains. If that turns out to be the case, any spring rise could be short-lived.

The corps has adjusted, favoring holding back water this coming spring on Lake Oahe, although Lake Sakakawea was to be given preference.

Even if there is a good spring rise, Bailey said, it would have to be fairly substantial to make a dent in spawning success. Ultimately, it will come down to precipitation and how that precipitation is managed.

“If we don’t get the precipitation, this recovery is going to take a while,” Bailey said.

One thing is almost certain, though.

“It’s going to be a much different fishing year in 2013.”

Tags: outdoors, sports, fishing