Giant Salvinia

Previously Funded Aquatic Invasive Species Research

Zebra Mussels

Measuring the risk of zebra mussel invasion in lakes downstream of infested lakes

Texas Tech University, Texas State University, US Army Corps of Engineers – Engineer Research and Development Center

Risk assessments based on predictive models that utilized environmental data coupled with DNA sampling helped determine which Texas lakes are at greatest risk of invasion by zebra mussels and were used to help guide zebra mussel early detection sampling.

Zebra mussel growth, reproduction, and invasion in Texas lakes.

University of Texas at Arlington

Research findings indicated that zebra mussels can decline in abundance in some lakes given certain environmental conditions exist, including extended periods of low pH and low water oxygen levels. Zebra mussel abundance can also be cyclical as their populations increase and decrease over time.

Aquatic Plants

Development of several new biological compounds in the laboratory to be used in management of giant salvinia.

Stephen F. Austin University

Giant salvinia is currently one of the most problematic aquatic plants in Texas due to its ability to develop dense mats that impact habitat for native fish and wildlife and impede boater access. This research developed natural ‘endocide’ compounds extracted from the giant salvinia plant itself. Testing showed that the endocides poisoned or inhibited growth of other giant salvinia. More research is needed to assess whether endocides have potential for helping to manage giant salvinia.


Evaluating research gaps related to tilapia in Texas

Texas Tech University

Invasive tilapia have been found in some Texas waters and can escape from ponds built on creeks. Researchers assessed the risk this invasive species poses to imperiled native fishes by reviewing published science and developing a computer model of areas in Texas that would be suitable for them to survive. This study contributed to review of regulations for exotic species that seek to prevent harmful impacts on native ecosystems.

Mapping the geographic range of bigheaded carp in Texas

Texas Tech University

Current regulations prohibit movement of live nongame fish in areas in Texas where invasive bigheaded carp have been found in the past to prevent them from being spread by bait bucket transfers. Researchers and TPWD biologists surveyed for these invasive fish using electrofishing and tested for their DNA in the environment. No live bigheaded carp or their DNA were found in new areas. This suggests that these prevention efforts have been effective to prevent these invasive fishes from expanding their range in Texas waters.

Age and reproductive status for invasive catfish in Landa Lake

Texas A&M University – College Station

Methods were explored for more effective management of invasive suckermouth catfish in Texas and information on catfish age, growth and reproduction was collected to assist future control efforts.