Fishing

Lake Bistineau March 10, 2010 Update

 

Temperatures are rising and "green-up" is around the corner. Fishing activity has increased over the last few weeks as the crappie, or white perch run has noticeably commenced. With summer just a few weeks ahead, inquiries about the lake level have increased. The most commonly asked question is, "What will the lake levels be during the summer?" My response is, "We don’t know." Plans are to fluctuate the water level throughout the summer, and I believe the lake level will be anywhere from pool stage to seven feet below pool stage. Rain events and implementation of a plan to address giant salvinia will dictate water levels. Next week, Secretary Robert Barham and Assistant Secretary Randy Pausina will be briefed on the plan.

Aquatic herbicide spray treatments commenced this week. The primary purpose of these initial treatments is to break up salvinia mats in order to facilitate their movement. We need the mats to move to areas we can potentially strand during water fluctuations. A remote sensing fly-over will be conducted for Lake Bistineau on Monday, March 15.

This Thursday, we will examine the lake by boat to locate mats with GPS (coordinates will be used in the fly-over), to understand how the lowering of the lake is affecting stranded plants and to further evaluate freeze damage. Initial evaluation of the plants indicates winter freezes caused significant damage to the plants, including bud damage.

Salvinia weevils were not detected in samples taken from the lake last week. We believe at this point that very few, if any weevils, survived the winter. A video flyover will be conducted as early as next week to determine and document winter effects on the lake. This will serve as a baseline just prior to the beginning of the growing season.

The department has no involvement with the airboat traffic and markers associated with the seismic activity on the lake. Those individuals are permitted to conduct this work, and we are not involved with their daily activities.

We’ve met with officials from Webster Parish regarding preliminary plans to construct a new boating access facility with access capability at minus seven feet. Our department is interested in assisting the parish to fund this endeavor. Enhancing and promoting boating and fishing access is very important us and is therefore addressed prominently in the plan.

We want to encourage everyone interested in working with the department to rehabilitate Lake Bistineau to stay informed and engaged. We can’t do this by ourselves, and we appreciate your interest and involvement.

On a personal note, working with the folks in the region has been very helpful and something that I’ve thoroughly enjoyed as we work through this process. It helps when everyone generally wants the same thing.

Mark McElroy
Fisheries Biologist

Lake Bistineau February 18, 2010 Update

 

I have received several questions recently regarding the current status of the lake and future plans.  I’ll take this opportunity to try and answer these as best as I can.

First, there is some seismic work for gas exploration being conducted on the lake which is why you’re seeing airboats and flagging.

Our plan does stipulate that cypress trees are contributing to poor water quality and lagoon building which promotes nursery building for giant salvinia growth.  Some cypress tree removal is recommended in our plan.

As of last Friday, the water level was three inches above pool stage.  Since the drawdown was initiated on September 16 (5 months ago), the water level has risen three inches.  The unusual fall and winter rain events have countered our intentions.  Unfortunately, we are also approaching the spring rainy season. 

I’ve received multiple inquiries regarding research by Dr. Lynn Walker at Louisiana Tech University.  We are very interested in his work and will continue to monitor his progress.  We will of course consider use of his research should he successful in acquiring an EPA label for use on giant salvinia.  As I understand, they are still conducting experimental trials and working on ways to ramp up production at this time.  However, let me remind everyone that EPA requires loads of statistical testing/reports in their consideration. Conducting these trials is very costly and will take time, probably years.  Our department will not use any herbicide for control of giant salvinia without a label stipulating its use for that plant.  

Right now, we suspect the salvinia weevils did not survive the freeze events.  We plan to reintroduce additional weevils later this summer pending their availability.  Additional samples will be taken next week to confirm our suspicions. 

We may need to close the gates again in the near future to remove the debris building up on the lake side. 

Next week, we will conduct a meeting to consider herbicide treatments in the lake for 2010.  I anticipate that as spring approaches, we will be putting crews out on the lake.

 

Mark McElroy
Fisheries Biologist

Lake Bistineau January 22, 2010 Update

 

Our staff has spent a great deal of time assessing the damage to giant salvinia plants as a result of recent freeze events. Damage to the exposed portion of the plants was extreme. However, just below the surface, the same plants exhibited green and potentially viable plant material. These observations are similar to those from previous winters. We suspect the plants will survive the winter and continue to grow throughout the spring.

Samples were taken in areas where weevils were stocked to assess their survival. I expect to have those results within the next few days.

I have received a number of inquiries requesting additional information about the drawdown. As of today, we have not achieved a seven foot drawdown due to heavy rainfall. Therefore, we anticipate the gates will remain open for some time. While the gates have been open, the increased rainfall has resulted in water fluctuations and stranding of the plants.

In fact, as we go forward, water fluctuations appear to be the best tool in our war chest to control this plant species in Lake Bistineau. We hope to continue manipulating water levels over the next few months. Therefore, I do not have a timeline for closing or opening the gates. It will depend upon the circumstances at that time.

The plan is undergoing review and rewrites.

You are encouraged to provide comments or questions on our website.

Mark McElroy
Fisheries Biologist

Lake Bistineau January 4, 2010 Update

 

Employees with DOTD successfully removed the debris in front of the control structure gates and subsequently reopened them last week. We anticipate keeping the gates open to resume the drawdown. The colder temperatures expected later this week should aid our efforts to kill more plants. Our staff will be monitor and assess the damage during the next few weeks.

I’ve received many emails regarding potential flooding while the gates were closed to clear debris. Luckily, the lake never rose higher than its previous state within the last few months. Removing the debris was necessary to resume the flow capability of the structure. I know that some are upset about the lake rising above pool stage in recent weeks. Unfortunately, we have experienced an unusually wet fall and winter. As a result of the heavy rain, our efforts to lower the lake down as planned have not been very successful. It’s important to realize that some flooding would have occurred regardless of whether the gates were closed based on rainfall totals.

Recall what occurred in recent months when the gates were open. As things stood, water was severely restricted due to debris buildup in front of the gates, and a decision was made to do what was necessary to resume water flow. I advise everyone to continue watching the weather forecasts to gauge potential lake rises.

I also received an inquiry about whether fish can be consumed after the application of department applied herbicides to the water. The answer is yes. We use herbicides approved by EPA and the state. The department is required to post advisories if applying something that could be harmful to humans or livestock. This is why we have insisted that people refrain from using “under the cabinet” solutions to treat the salvinia. There are many chemicals that will affect these plants, but legally we have only a few at our disposal. It takes millions of dollars and stringent testing to get a chemical label that stipulates its safe use.

I anticipate the completion of a plan this week and will forward it up the ladder for consideration. In an ideal situation I would like time to assess the lake bottom, but this is not possible due to the high water. Therefore, I have decided to start the process of review and consideration without that important information. Please keep in mind that my work needs to be reviewed by others prior to making it available to the public.

Thank you for your patience.

Mark McElroy
Fisheries Biologist

Lake Bistineau December 18, 2009 Update

 

I will speak with officials at DOTD early next week to see when the gates can be reopened. It is sometimes difficult to get things done during the week of Christmas. I would like to resume the draw down as soon as possible.

There has been a great deal of confusion and misinformation surrounding Lake Bistineau, and I would like to take a minute to clear up several items. First, the gates only allow for a draw down to seven feet below pool stage. We may decide to bring the lake down even farther, but in order to do so we will need to improvise. This has not been decided yet. We may also close the gates again in the near future to fluctuate water levels. This will be determined further into the process.

There has been a lot of discussion about the use of vinegar to kill salvinia. Vinegar is acidic and will indeed burn the plants exposed above the surface. However, the plants extend below the surface and based on our trials earlier this year, the plants grow right back. For that reason alone we are not interested in using vinegar. More importantly, vinegar does not have an aquatic label, and we are prohibited by federal law to use it in this situation.

Vinegar acts as a “contact” herbicide, although not a very successful one because it does not do a good job of killing the plants. Spraying “contact” herbicides will play a role in our plan to control salvinia, however there will be a de-emphasis in their usage going forward. If one looks at our spraying efforts over the last two years, it is easy to conclude that spraying along is neither economical nor effective.

Please note: There is now a place on this site to submit public comment. I am requesting all individuals, including those who have been emailing me directly, use this new feature to communicate. I will try to answer any questions and address concerns in future updates.

Mark McElroy
Fisheries Biologist

Lake Bistineau December 14, 2009 Update

 

Today, the department is requesting the Department of Transportation and Development close the gates at the control structure at their earliest convenience. There are two recommended reasons for the temporary closure. A significant amount of debris has floated down the lake and it either lodged in or in front of the control gates. Removing the debris can be accomplished safely while the water flow is reduced.

Also, closing the gates allows the lake level to increase, thereby increasing the potential drawdown effect on the plants. Water level fluctuation is one of many tools that can be used to control the salvinia on Lake Bistineau.

Mark McElroy
Fisheries Biologist

Lake Bistineau December 8, 2009 Update

 

The department is poised to finish the final component of a long-range plan to address giant salvinia on Lake Bistineau once the lake’s water level reaches seven feet below pool stage. To date, fall and winter rain events have kept the water level from dropping much below three feet.

The number and placement of trees in the lake is contributing to the proliferation of this plant. The trees offer cover from freeze damage, slow water velocity which encourages silt depositing and the establishment of nursery areas, prevents plant movement and inhibits spraying. Strategic tree removal in relation to nursery areas and the spillway will be one control method considered when the water is down.

After aerial inspection in November, we observed a significant reduction in plant coverage due to heavy rainfall throughout October. While some plants passed through the control structure, stranding of the plants within the lake was the main contributor for the reduction. This proves that utilizing water level fluctuations to strand plants is a successful control method and why much of our attention has been focused on using this method going forward. The immense watershed provides us with more capacity to fluctuate water levels year round.

I have participated in several productive meetings in recent weeks and more are planned. I anticipate meeting with the Louisiana State Land Office, Louisiana National Guard, Department of Environmental Quality, Bossier Police Jury and state legislators in the near future. Most of the meetings are follow-up meetings to address particular issues.

Mark McElroy
Fisheries Biologist

Lake Bistineau October 20, 2009 Update

 

Lake levels are still on the rise as a result of heavy rainfall during the last few weeks. Therefore, the drawdown to seven feet below pool stage is behind schedule. The goal of the drawdown is to strand the salvinia plants in the lake, but high water levels have allowed the plants to spread into areas that typically do not have water.

The increased rainfall has however caused the salvinia to move, and many acres once covered with giant salvinia have passed over the spillway or through the water control structure. Most of the plants are piling up behind the water control structure on Loggy Bayou Management Area.

Once the lake is down, department staff will further inspect the area. The information gathered will be used in developing a long-term plan for the lake. Efforts will focus on areas showing little response to the drawdown and potential causes for the lack of response. Many of these areas harbor salvinia and become nurseries for the plant.

Excavation and tree removal may be necessary in order lower water levels in these areas. If so, standard procedure will require us to obtain a U.S. Army Corps of Engineers permit. For those areas on private property, an executed agreement will be required.

Despite delaying the drawdown, the high water event does create a positive in this instance. The effects of the seven foot drawdown will be more significant than if the lake was at its normal stage.

We have yet to determine when the gates will be closed. Many factors will play into this decision. We are interested in doing some modifications to the spillway and lake bottom. Some of this work will require the lake bed to be bone dry. Other considerations include permits, MOUs, advertisement for bids, contracts, partnerships and funding. There is a possibility that the lake will be left down for another year or longer.

Mark McElroy
Fisheries Biologist

Lake Bistineau September 28, 2009 Update

 

The Department of Transportation and Development opened the gates on the Lake Bistineau water control structure to commence the 2009 drawdown of the lake. The lake level will be reduced by seven feet. However, recent rain events have kept the lake up, extending the amount of time required to reach minus seven feet.

This week, LDWF biologists will conduct an aerial assessment of the lake to determine a base line for giant salvinia coverage. In addition, they will evaluate the watersheds that contribute runoff to the lake to determine the extent of giant salvinia in the upper reaches. Lastly, they will take a look downstream of the dam. Several more aerial assessments are planned as the lake level lowers.

The purpose of the drawdown is to strand giant salvinia in the lake. Many have expressed concern that the water control structure does not create a situation where the plants can exit the lake. In this instance, it is not necessary. Salvinia is a fern, and if unable to access water, will dry out and die. Last year’s drawdown, along with foliar herbicide treatments, reduced giant salvinia coverage from 4,500 acres to about 850 acres.

At this time, there are no plans to close the gates. During the drawdown period, the department will evaluate the use of water fluctuation to facilitate plants to move from areas that will not drain. In order to do so, the gates may be closed; the lake will be allowed to fill to a certain level below pool stage and then opened after the plants move to stranding areas. The long-term plan to control giant salvinia in Lake Bistineau will place heavy emphasis on managing water level fluctuations.

The problems associated with Lake Bistineau extend far beyond the salvinia crisis. Many human activities have and continue to contribute to the degradation of the lake’s ecosystem. Over the past few weeks, we’ve spent a great deal of time developing a better understanding of water quality issues in the lake and watersheds. Our discoveries answer some very important questions as to why giant salvinia grows exponentially in this water body. There are many outdated, poorly maintained sewage treatment facilities throughout the watersheds that are responsible for a constant influx of nutrients. As a result, giant salvinia is being nourished, or fertilized in Lake Bistineau.

Sewage discharge is regulated by the Department of Environmental Quality and Department of Health and Hospitals as well as the parishes. Going forward, this issue must be addressed. This department will make the case with those government entities that have jurisdiction over this matter that non-compliance with state and local ordinances is contributing to lake degradation and ultimately giant salvinia growth. Addressing this situation will require routine monitoring of all sewage discharge, which in some instances will include maintenance or new installation.

Therefore, the rapid growth rate and resulting immense coverage of giant salvinia on Lake Bistineau can be directly linked to sewage discharge present in the water body.
Neglecting to address contributing factors will undoubtedly lead to less than desirable long-term results.

Mark McElroy
Fisheries Biologist

Lake Bistineau September 10, 2009 Update

 

Our friends at DOTD alerted us last week that they will require an additional week to finish their work behind the spillway.  The structure is their responsibility, so we will wait patiently for this work to be completed and look forward to Wednesday, Sept. 16 to begin the drawdown.

Once the drawdown begins, our team will begin a new phase of investigating the issues that plague Lake Bistineau.  Most of you who use the lake are aware that there are back water areas that don’t dewater with a 7 foot drawdown.  Essentially, these areas are cut off from main channels and serve as nurseries for giant salvinia.  This situation is unacceptable if we are to gain control of the plant.  It will be vital for our team to evaluate these areas to understand what can be done.

The complexity of the terrain and sheer number of these areas will make reconnaissance difficult, especially in the upper reaches of the lake.  While much of this work will be performed by ground crews, some of the work will be coordinated with aerial surveys.  Large areas will receive the highest priority.

There is a still lot to be understood, and the answers seem to come in steps.  Obviously, getting the water down is a giant step.  

Mark McElroy
Fisheries Biologist

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