Heavy rainfall diluting saltwater levels and impacting the food our coastal fish like most ... brown shrimp _lowres

Advocate staff photo JOE MACALUSO Alex Heintze, a teenage member of the Junior Southwest Bassmasters of Denham Springs, shows off two of the bass he took to finish second in the Co-Angler Division of the recent Pro Bass Challenge. High school anglers, like Heintze, will show up on south Louisiana waters this week for the first Louisiana High School Bass Championship. Weigh-in is set to begin at 4 p.m. Saturday at Bass Pro Shops off South Range Avenue in Denham Springs.

Wonder what the effect of all the water, the runoff from all the rain that’s descended on south Louisiana, will have on fishing during the coming months.

First, consider the effect is has on the critters fish like speckled trout, redfish, flounder, sheepshead and drum eat.

What about freshwater, and the bass, bluegill, sac-a-lait, catfish and goggle-eye?

With the State Shrimp Study biologists and data gatherers working test trawls along the coast, the issue of nearly two weeks of a copious amount of rain comes at a time when brown shrimp are moving into the coastal marshes.

Rainfall dilutes saltwater levels, which reduces the area brown shrimp need to grow. Cold rain and cloudy conditions complicate the process, too. The baseline for brown shrimp habitat is 10 parts per thousand salinity, and a warming sun is needed to increase water temperatures to at or near 70 degrees to allow for brown shrimp growth.

An offsetting factor has been the almost constant southerly winds that have helped push saltwater into the marshes to help with the salinity factor, but, overall, water temperatures have cooled slightly since it was measured at 71 a couple of weeks ago in the southern reaches of the Barataria Basin.

Before the onset of the wet weather, conditions in the offshore waters off Terrebonne Parish were so good that the Shrimp Study group advised Department of Wildlife and Fisheries’ secretary Robert Barham to open the state offshore waters to shrimping from Caillou Boca west to the eastern shore of the Atchafalaya River Ship Channel at Eugene Island. That was because sampling data showed white shrimp living in those waters since moving from the marshes in December had grown to a size large enough for the market.

More will be known about the brown shrimp when the Wildlife and Fisheries Commission meets May 7 in Baton Rouge.

Shrimp Study leader Marty Bourgeois will reveal data the commission will consider for the opening days of the spring inshore shrimp season in the state’s major “inside waters” zones.

Brown shrimp is an important factor for speckled trout catches. Last year’s unusually cold spring and constant north winds sent brown shrimp from the marshes into the nearshore coastal waters.

The winds also broke up the big pods of shrimp usually seen during the spring. That broke up the schools of trout, too. A downturn in this important food source for predator species means a downturn in trout catches.

About the rivers

Spring flow from the Mississippi, Atchafalaya and Pearl rivers heavily influence salinity levels in the marshes, too, and the rivers have been running high from the spring floodwaters. The Pearl River continues to rise from recent heavy rains in its watershed that begins in central Mississippi.

The latest 28-day projections for the Mississippi River shows crests of 61.5 feet on May 4 at Red River Landing, 34.5 feet at Baton Rouge on May 6, and 14 feet at New Orleans on May 6.

The Atchafalaya at Bayou Sorrel will hit the 9-foot mark on the Bayou Sorrel gauge and get to 5.6 feet at Morgan City, both levels are slightly below flood stage with no downturn for at least the next 10 days.

For this week

Rainfall is the reason there continues to be a no-wake warnings posted for Belle River and the Pierre Part area. Water levels are holding, even swelling on tides and southerly winds, and quieting what usually is very active bass, sac-a-lait, catfish and bream fishing during a time when most all anglers consider the Atchafalaya Spillway to be too high to fish.

Eugene Hoover, the state’s Junior Bassmaster director, has set a tentative site of Doiron’s Landing in Stephensville for the coming weekend’s Louisiana High School Junior Bassmaster State Championship.

“We’re going to have to see what the water conditions are before we set the (fishing) location,” Hoover said, adding he expects the ever-growing number of high school anglers from across the state to show up for registration beginning at 5 p.m. Friday at Bass Pro Shops in Denham Springs. No matter the fishing location, Hoover set the weigh-in to begin at 4 p.m. Saturday at Bass Pro Shops.

The high water in Belle River has also twice postponed the annual Seniors Bass Tournament. Organizer Wayne Tucker said the gathering of 55-and-older anglers will be held, most likely on a Friday in the middle of May.

And, for the Florida Parishes rivers, Jeff Bruhl reported a 12-pound stringer won a bass tournament on the West Pearl last week, but that high water levels will continue to plague that system.

He said the Tchefuncte River was muddy and that black water was oozing from the pockets off the main river and on the lower end, and said subdivision canals along the Tickfaw have been producing bass averaging 1-2 pounds.

“If everything levels off and the rivers can ‘get right,’ we should start seeing better action in the first week of May in all these rivers,” Bruhl said.

“We’ll be in a post-spawn phase, and that means going with (baits) like trick worms and finesse worms, and hopefully by then we’ll see the goggle-eye get active, too.”