Walleye

Regulations for Lake Sharpe Walleye

Walleye limits for Lake Sharpe are the same as the South Dakota statewide standards of 4 fish daily and 8 in possession.  The daily limit may include only one walleye 20 inches or longer, year-round, and a 15-inch minimum length limit is in effect during all months except July and August.

 

Walleye Fishing Trends for 2009

Fishing activity peaks at different times in different areas on Lake Sharpe.  Fishing usually is best in the spring in the upper region, near Pierre, and then progresses downstream to the lower third of the lake.  Walleye fishing in the Pierre area is usually best in the spring and fall.  In June, fishing improves in the lower third of the reservoir and remains good throughout the summer. 

A walleye population, as with any fish population, has many ups and downs due to many factors, such as weather and water conditions, food resources, and angler harvest.  In 2008, the walleye abundance index was 19 fish per net, which is slightly lower than the average, but has increased since 2004.  The increase in abundance was largely due to high production of young walleye during 2005-2008.

The abundance of harvestable size fish (over 15 inches) was lower in 2008 than in the past, due to many factors including past angler harvest and lower production of young walleye from 2001 to 2004.  Of the 19 walleye caught per net in 2008, on average, only 3 walleye per net exceeded 15 inches.

However, the future is bright for Lake Sharpe.  During the years of 2005 through 2008, Lake Sharpe experienced average or above average production of young walleye.  These fish began to reach harvestable size (> 15 inches) in 2008.  Small walleyes will make up a large portion of the catch in 2009. 

How easy fish are to catch is influenced by many factors including the number of adult walleye in the population, ages of fish (younger fish bite better), and how abundant food is.  If the fish have a limited supply of food, catch rates generally increase.  In 2009, catch of walleye should be good with the walleyes produced during the 2005-2008 period making a large portion of the catch by anglers.

Gizzard Shad: Lake Sharpe’s Primary Forage

In Lake Sharpe, gizzard shad are the primary forage species.  The majority of young gizzard shad die each winter due to cold water temperatures and a few adults survive each winter.  In the spring, these adults spawn and produce thousands of young that feed Lake Sharpe fish for the rest of the year.  If spawning conditions are not ideal for gizzard shad, there will be less food for walleye and other predator species.  When conditions are right, adult gizzard shad will produce a high number of young, providing ample food for all predatory fish in Lake Sharpe. 

In Lake Sharpe, fishing patterns develop due to the reliance of walleyes and other fish on young gizzard shad as food.  In the spring, when gizzard shad numbers are low, walleye are easier to catch.  In the summer, as the gizzard shad become large enough for walleye to eat, walleye are harder to catch because they have full stomachs.  In the fall, walleye become more susceptible to anglers as they migrate upstream and concentrate in the upper end of Lake Sharpe.  Also, as the water cools in the fall, walleye become more active and easier to catch.

How old is the walleye I just caught?

Walleyes in different lakes grow at different rates.  A lot of factors affect how fast a walleye grows, including water temperature, amount of food and time of food availability, and spawning stress.  Just like humans, some fish eat more and may grow faster than others.  In Lakes Oahe and Sharpe, biologists have aged walleye as old as 16 years of age.  In most cases, fish continue to grow longer and larger as they age.  The chart below describes the growth of walleye in Lake Sharpe.  A lot of years are invested in growing walleyes large enough for anglers to keep.  Generally speaking, it takes four years to raise a walleye to harvestable length (>15 inches) in Lake Sharpe and nine or 10 years to grow a 20 inch walleye. 

An Age Estimate for Walleye in Lake Sharpe
according to the length of walleye.

Age is approximate.  Length is in August.

Why not stock Lake Sharpe with walleye?

 

Factors such as cool or unstable weather, water management of the Missouri River system, and drought affect how successful the spawning season and natural production of walleyes are each year.

Lakes Francis Case and Sharpe have traditionally had consistent production of young walleyes. Lake Sharpe has never been stocked with walleyes and Lake Francis Case was only stocked with walleyes in 2002 because water management by the Corps of Engineers resulted in a decrease in water levels during the spawning season.

In many lakes with a history of good natural walleye production, stocked fish usually survive well in years when natural production of young walleyes is also good.  When natural production is poor, stocking often has poor results.  The only time this would not be the case is if some environmental factor negatively affected the walleye spawning season, like a decrease in water level.  Current management plans are to only stock Lakes Sharpe or Francis Case if water management during the walleye spawning season would negatively impact the potential for a good year of natural production. 

When walleyes are at a low abundance, the stage is set for a good year of natural production, as shown by high walleye production in 2005.  The major factors affecting successful spawning seasons in the future will be weather and the possible continuation of the drought in the Missouri River basin.