Resources for Boat Owners and Marinas

Moving Boats Moves Invasive Mussels

Invasive mussels attach to boats stored in the water and can cause serious damage to the boat. A boat that has been stored in the water on a lake known to have zebra or quagga mussels (ZQM) will have mussels attached to it—often in crevices where you can’t see them. If the boat is moved without being properly decontaminated, it can carry a colony of adult mussels capable of infesting a new lake. Invasive mussels are now found in many Texas lakes.

You Can Help Stop Invasive Mussels

A single marina, boat owner, boat hauler, boat inspector, or anyone who sees or suspects invasive mussels are attached to a boat can prevent an infestation at a new lake. Preventing ZQM invasions can save millions of dollars in damages to taxpayers, boat owners, and marinas each year. Infestations of ZQM are irreversible: once they’ve invaded a water body, there’s no getting rid of them or their damaging impacts.

General Information

Requirements for Boat Owners

  • If the boat has been stored in the water on a Texas lake known to have ZQM, or if it is coming from an out-of-state lake with ZQM, it must be decontaminated before it can be launched. It only takes one boat to cause irreparable damage.
  • In Texas, it is unlawful to possess or transport ZQM dead or alive, even unknowingly.
  • Texas Parks and Wildlife Department is here to help boat owners avoid costly citations by properly decontaminating and drying their boats before moving them to another lake. Email or call our 24/7 hotline at (512) 389-4848 for guidance.
  • Boats with attached ZQM may be moved to a maintenance shop for cleaning or other maintenance provided the department is notified at least 72 hours in advance using the Boat Maintenance Movement Notice form. Boats moving to another lake after maintenance may require inspection and decontamination.

Resources for Boat Owners

How Marinas Can Help

  • Follow entrance and exit procedures to protect the lakes you love. Work to prevent ZQM from entering or leaving the lake on your watch. Treat all boats from out of state as high-risk. Remember: lakes that already have zebra mussels can still be invaded by quagga mussels, and they can cause even more problems.
  • Be informed. Stay up to date on the current status of ZQM in Texas lakes so that you can assess the risk posed by incoming boats. 
  • Share information and advice often with slip tenants, boat haulers, other marinas, in-water construction companies, and anyone else working with boats on your lake.

Resources for Marinas

Impacts of Zebra and Quagga Mussels (ZQM)

Zebra and quagga mussels are invasive species that reproduce rapidly and pose a serious threat to Texas lakes. These tiny mussels can have devastating economic, recreational, and environmental impacts. They attach to boats stored in the water, marina infrastructure, and water intakes, causing damage that requires costly repairs. They can also cover shoreline rocks and litter beaches with treacherously sharp shells.

When ZQM infest boats, they seek out dark crevices such as through-hull fittings and intakes on motors, clogging and damaging motors, pumps, and intakes, leaving boat owners with the repair bills. They can also colonize the hulls of boats and cause pitting. Marinas on lakes known to have ZQM may see costs rise due to increased need for rental boat cleanings and repairs to pumps and underwater infrastructure.

Once a lake has ZQM, there is no way to eliminate them, so it is important to stop them before they arrive. Invasive ZQM cannot move upstream or to other river basins on their own—they can only move by hitching a ride on boats, trailers, or other equipment used in the water. Boats that have been stored on lakes known to have ZQM pose the highest risk for moving them and causing new infestations.

TPWD is here to help!

For questions about invasive mussels, boat inspection and decontamination, regulations, or what to do if you encounter an infested boat or suspect a watercraft is carrying ZQM, email or call TPWD’s 24/7 hotline at (512) 389-4848 for assistance.