The Birds of Lake Martin, La

White Ibis feeding on the floating mat of plants in Lake Martin


As a swamp tour guide in the rookery at Lake Martin for over 20 years, my observations of the bird population and it's gradual modifications, gives me an opportunity to present an explanation of an unsolved mystery.

I have witnessed sometime very subtle or dramatic adjustments in nesting patterns in relation to climate fluctuations, as well as government, conservation groups, local residents, and my own as well as other swamp tour operator activities.

A sunset on a Lake Martin Swamp Tour

I have been in the rookery for over 20 years, day and night as a tour guide, with a focus on the birds, alligators and plant life as well as the overall ecology and natural beauty. I know what the birds will and will not tolerate during the nesting season. With that knowledge, I have operated as close as possible without causing a disturbance of nesting activities.



The mysterious disappearance of the birds at Lake Martin in March of 2006 is no great mystery to me. I have been watching a gradual decline in the population of wading birds for nearly eight years since the water was first being lowered or drained from the lake and nesting area beginning in 2001. (Click the link above to read the article I wrote in another blog in February of 2009)

Not only has the water been lowered every year in the autumn season, by pulling the drain plug, it has been kept below normal year round(by about 18", compared to where it was at its highest in 2001) and rainfall has allowed to escape all year long as seen below.



It appears to me that when the water was allowed to rise to it's highest levels(between 1996-2001), the bird population rose to it's highest levels. It is common knowledge that these birds nest in trees which grow in standing water year round.

The decline is coincidental with two or maybe three other significant factors making it difficult to pinpoint any one source as the cause of the decline of the bird population.

1. The presence of poachers taking birds at night.

2. The application of herbicides to control(or completely destroy and eliminate) the floating mats of native indegenous plants by The Louisiana Department of Wildlife and Fisheries in the rookery and feeding areas around the lake, which supports the food chain leading up to the nesting birds in the rookery.

3. A swamp tour guide doing night tours in the rookery between 2000 and 2006.

I began doing swamp tours at Lake Martin full time, in 1996, having wet my feet as a tour guide in the Atchafalaya Basin for over ten years prior to that. In the Atchafalaya Basin, I noticed two things that I did, which would disrupt or displace birds nesting activities.

1. Approaching a bird nesting site when the nest was under construction prior to laying eggs. Through trail and error, I learned that if I passed close to a new nest, when it was under construction in the spring, the bird would often abandon that site and start another nest elsewhere. Because these nests were not there the last time I passed a few days before, these disturbances were accidental and thus often unavoidable. If I noticed the new nest under construction as I approached from a distance, and gave the bird some space and time, thus allowing it to construct the nest, lay eggs, and get settled in, I could later pass very close to the nest and not cause a disturbance.


2. Accidentally entering a new area containing a roost or nesting area at night with a big light such as a Q-beam.

I decided to use Lake Martin as my primary tour site location in 1996, because it was clean, quiet, easily accessible to tourists from Interstate 10, and had a relatively stable water level year round. But the most prominent benefit of doing tours at Lake Martin was the amazing variety and abundance of wildlife. For about the first year, I wondered why was this swamp so wildlife intensive compared to everywhere else. After plant control arrived at Lake Martin and destroyed the floating mat of plants, I realized the benefits of floating mats of plants in swamp ecology and thus the abundance of wildlife in conjunction with plants.

It was then, and still is by far, the most reliable year round, wildlife intensive tour area I have ever visited. But, when I first started doing tours there full time in 1996, there was no plant control, or water management(annual drainage) and the only time the Louisiana Wildlife and Fisheries went there, was to enforce laws.

As soon as plant control arrived at Lake Martin, I understood why plant control was so destructive to the overall ecology and why there was so much wildlife prior to plant control destroying the food chain there.

At that time, I did not consider that the high water levels could be a primary cause of the population growth of the nesting wading birds in the Lake Martin rookery.

A drought caused a fish kill in 1996 and 1997. Instead of recognizing the drought as the cause of the fish kill, the Wildlife and Fisheries biologists blamed the fish kill on too many plants in the lake.

The Louisiana Department of Wildlife and Fisheries, Division of Plant Research and Control first came in May of 1997 with a crop duster airplane and applied a granular herbicide to the lake area. That first wave of plant control killed all of the submerged plants(hydrilla, coontail, and aquatic bladderwort)in the lake which resulted in a total fish kill and there were no indigenous fish in the lake for 4 years after that. Except for the Chinese Carp introduced and used for plant control.

Plant control then began to apply 2-4-D (also known as agent orange in an other place and time)to destroy the floating mats of plants on the north, east, and west sides of the lake. This is a critical component of the ecology that supports the food chain that leads to and feeds the wading birds and every vertebrate and invertebrate in between the plants and the alligators.

The next manipulation of the ecology came when biological studies by Federal Wetlands Center biologists proposed that lowering the water levels might improve water quality. This proposition was based upon an assumption or "guess" that poor water quality might be the cause of the population decrease.

These biologists who spent a few days a month on the lake studying the water quality problems and taking water samples during the drought period, made a proposal that we should begin to annually lower and manipulate water levels in an effort to "improve" water quality. Unfortunately their research was conducted primarily during the drought period and not continued during normal rainfall activities, when rain could recharge the oxygen supply and allow fish to live in a lake with an abundance of plants. Through all this, the Lake Martin Advisory Committee(a group of local water front residents) hoped to protect the ecology and planned to maintain or "keep things as is".

The problem with that plan is, that the lake, it's natural inhabitants and the ecology changes naturally from year to year due to climate variables. During drought years when the water levels are lowered naturally, it is very different than in flood years. And, in a hard winter season it freezes the surface of the lake and swamp killing most of the surface vegetation. This climate change which is infrequent, but normal, once again allows the natural dying off of certain plant species to generate an opportunity for the proliferation of new species to dominate the water/landscape in the growing season of the following year.

To this effect I have witnessed salvinia(a.k.a. greater duckweed) as the primary floating plant in the late 80's be replaced by lesser duck weed in the 90's and then back to salvinia in the 21st century. Also for a brief time in 2000 through 2002, water hyacinth dominated as the floating plant mat. As a result of plant control herbicides destroying the indigenous plants(such as aquartic waterwort, frogbit, and dollar bonnet) that formed a mat of plants preventing the movement of water hyacinth, the water hyacinth(a non-native) was able to drift and take over or dominate as the primary surface plants in the lake. In my opinion, in essence we had no plant control problems until governmental plant control arrived and started trying to fix something which was not broken.

Plant control activities which included herbicide application and lowering the water levels are in my opinion the primary reason the birds began to mysteriously disappear from Lake Martin.

Because living plants on the surface and below the water absorb nutrients, they are effective water filters, balancing the chemical exchanges of dead, decaying plants feeding living plants. If it weren't for living plants and bacteria devouring nutrients released into the water by dead decaying plants, the water would have a nutrient overload, or in lay mans terms be a cesspool. Because man has altered the hydrodynamics of swamps, bayous and rivers, in the name of human progress, swamps are often regarded as unclean due to an interruption of natural processes. For this reason, man then attempts to control or minimize plant mass by killing off a portion of the plants in the ecosystem. Unfortunately that attempt is usually government overkill in my opinion.

When left alone, to evolve naturally, swamps can and will within themselves control biological shifts in plant composition and climate changes that are natural mechanisms which are cyclical and balanced.

Although the water was not lowered by drainage in September 2009 for the first time in nearly a decade, we still must face the specter of government plant control applying excessive amounts of herbicide and trying to turn the swamp around Lake Martin into a lake with trees in this coming growing season in 2010.