LeBlanc: Update on the invasion of foreign plants in our waterways

Well folks we in the great state of Texas are still under attack by foreign plants. It seems like we are constantly battling infestations of these imports in our lakes and let me list a big one that is on my mind so you can get an idea of which I speak: Giant Salvinia.

Giant salvinia has been present in Texas for just about 20 years. It was first discovered by the TPWD in a pond at a Houston school in 1998 and had to have come from somebody who put in the “decorative plants” from their aquarium in it undoubtedly to make it pretty.

When I first heard that statement describing the origin for that invasive plant into Texas I, being perfect and all knowing, ranted about the stupidity and ignorance of some folks to do such a thing. Now I have to admit that the possibility does exists that I don’t know everything and thought I had gotten past that erroneous line of thought my first day in the United States Air Force. I also accept that every one of us is ignorant about many subjects. However, that being the case we are responsible to do some basic investigation and use some common sense before we act regarding something we are ignorant about before we break the law and have the opportunity to cause a catastrophic problem to our state.

I think almost everyone who has been in this area for a while is probably familiar with the problems and costs generated to try and eliminate this insidious plant, or at least keep it under control. This one we know is but one product that has gotten here because of the lack of enforced restrictions controlling what the importers of aquarium life have brought into our country.

So here we are today and the monster released in that little pond has since spread throughout East Texas. In addition to its current presence in most lakes this invasive plant has been expanding over four Texas lakes in the last three months: Lake Murvaul, Lake Palestine, Martin Creek Lake, and now Lake Fork. FYI, the only natural, freshwater lake in Texas, Cado Lake, is also sporting a large infestation of the plant.

Oh, in case you wonder Lake Conroe has Giant Salvinia in it also, but it is mixed in with native plants so spraying is out of the question because the native plants are important in keeping the giant salvinia contained and under control. Also the TPWD have used specialized, imported weevils that only eat salvinia located onto the the plants to help keep them knocked down and under control. That treatment has proven effective in such cases as we have in Lake Conroe.

Of course there are always those motivated and primarily driven by greed and not scientifically proven facts and performance history. For example that is what happened the last time we had too many triploid carpe put into the lake to eliminate the hydrilla while at the same time eliminating about all of the native vegetation in the lake. Such actions could well be enough now to trigger an infestation of giant salvinia in our lake by eliminating the containing native vegetation. We didn’t come out of that fiasco unscathed because the actions of a few ended up destroying spawning habitat and hiding places for hatchling fish resulting in a sharp decline of crappie and other native animals in our lake for many years because of the loss of native vegetation.

So who is on the front line of the battle against this foreign invader? In Lake Conroe it is the TPWD and the San Jacinto River Authority, and in Lake Livingston it is the TPWD and the Trinity River Authority. The TPWD is providing the biologist and most of the financing is coming from the river authorities to provide the weevils and contract the companies to spray the infestations large enough where spraying is the best solution and want completely destroy the native vegetation.

I have spoken to TPWD Biologists Mark Webb who is over our area and TPWD and John Findeisen, TPWD aquatic invasive species team leader, last week and both are concerned but optimistic that everything that can be done is being done to fight the ongoing giant salvinia problem. There are many other controlling factors that they are not sure about regarding the spreading of this plant such as water composition, weather, and other possibly unknown factors, but with the knowledge and tools they have available at this time they feel we are holding our own in the battle.

Okay now to what can we outdoors types do to help control giant salvinia and hinder the spread of it? I think most anglers and pleasure boaters know by now the phase, “Thoroughly clean, drain and dry,” your boat every time you take it out of the water and before moving it to another body of water. That process will go a long way to help eliminate the spreading of a number of foreign invasive species.

Besides the obvious listed boaters let me address the waterfowl hunters. Findeisen noted all equipment that comes into contact with the water is capable of harboring invasive species – including waders, boats, trailers, and decoys – and can quickly spread them to new places and destroy aquatic habitats. “Any gear that has been in the water can carry invasives and must also go through a thorough clean, drain and dry process,” Findeisen said. “This includes decoys, waders, and marsh sleds.”

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