Salvinia threat on Rayburn

It has long been rumored and was finally confirmed Monday, Jan. 28.

Giant salvinia has been found on Sam Rayburn.

The plants were found floating in the Coleman Creek area. Initial surveys show that the plants presence may be isolated to the area, yet further scouting of the reservoir may prove otherwise.

Giant salvinia was officially confirmed in Sam Rayburn on Monday, January 28, after reports from weekend anglers were investigated.

Currently, efforts to contain the infestation are underway, and will be followed by physical and chemical treatments. Additional surveys will be conducted to determine if giant salvinia has spread to other areas in the lake.

Giant salvinia is an invasive floating aquatic fern from Brazil. According to Dr. Earl Chilton, TPWD aquatic habitat enhancement program director, giant salvinia is one of the world's most invasive aquatic weeds.

"It has caused problems in Australia, New Guinea, New Zealand, Rhodesia, and Sri Lanka to name a few," Chilton said.

Under ideal conditions, giant salvinia populations can double every 5-to-8 days, are resistant to cold weather, and can survive for weeks out of water if kept moist. Once established, the fern forms dense mats that eliminate all other aquatic vegetation in the area, even plankton, which are vital to healthy fish populations.

Reports of giant salvinia on Sam Rayburn have been investigated before, yet the plants have always proven to be common salvinia, which has been present for 10 to 12 years in Sam Rayburn.

This marks the first time giant salvinia has been positively identified on the lake, although it may have been present for some time.

Since giant salvinia moves about with the wind, plants are easily transported from lake to lake by boats or boat trailers. The plant was possibly transported from Toledo Bend or Dam B, and introduced into Sam Rayburn by a boat trailer.

"It is illegal to possess or transport giant salvinia without a permit, but these people wanted to do something to help protect their lake," Howard Elder, aquatic vegetation biologist for the Texas Parks and Wildlife Department said. "Involving them as permitted volunteers gives them ownership of the management of the water they live near."

Giant salvinia has been present in Toledo Bend and managed by Texas Parks and Wildlife since 1998. The plants were also recently discovered in Dam B in 2007. It is important to check your boat and trailer for plants after loading or unloading your boat, and remove any plants you may find. It is now a Class C misdemeanor to posses or transport aquatic vegetation from one reservoir to another.

Signs were placed around Dam B warning people of giant salvinia's presence and steps they can take to help prevent its expansion.

"The signs will help people identify giant salvinia and encourage them to inspect and clean boats and trailers before leaving launch areas," Elder said.