Fisheries biologist Quintin Dean has a passion for protecting native vegetation.
“I grew up in the desert southwest and the miracle that is green plant life will always mystify me,” said Dean, Fisheries Biologist with the Texas Parks and Wildlife Department (TPWD).
Dean’s passion has led him to oversee the native aquatic plant nursery at Lake Murvaul for the Texas Parks and Wildlife Department. It is one of several such nurseries in locations around the state cultivating native plants like water willow, delta arrowhead and water stargrass to aid in habitat restoration in lakes and reservoirs.
“A common saying amongst anglers and biologists in the south is “Grass equals Bass,” Dean said. “Aside from its rhyming appeal and concise nature, this phrase has percolated across angler and biologist communities because it is true. My job is to enhance and maintain quality fishing opportunities for the people of Texas. Aside from enjoying the work, I have an obligation to improve the resource and want to tackle the problem with a full toolbox.”
Restoring native aquatic plants is how Dean and the teams at TPWD are doing that.
Native aquatic plants serve many purposes: they provide essential cover and nursery habitat for fish, prey, and other species; attract macroinvertebrates that are important food sources in lakes; segregate nutrients and other pollutants in their tissues to improve water quality; and stabilize the shorelines of reservoirs and riparian banks preventing erosion and sedimentation.
Aquatic plant nursery at Lake Murvaul in Texas operated by the Texas Parks & Wildlife Department. (Photo credit: Texas Parks & Wildlife Department (TPWD)
The plant nurseries established by the Texas Parks and Wildlife Department are one part of the habitat efforts that have taken place in the state for several decades. In 2021 these efforts were consolidated into what is known today as the Habitat and Angler Access Program (HAAP).
The seven operating aquatic nurseries in the HAAP program provide a platform to align multiple stakeholders and partners around the state for a common goal. The TPWD manages four nurseries at Lake Murvaul, College Station, Abilene, and at the Texas Freshwater Fisheries Center in Athens. Three additional nurseries operate with partner collaborations at Lake Conroe, Lake Houston and Lake Livingston.
These nurseries enable the development of native plant communities by using species that occurred naturally within given regions, each occupying a different niche in the ecosystem. Growing and reestablishing the native plant communities through a controlled process serves to restore what nature intended.
American lotus in a herbivory excluding cage. Cutgrass in the background. (Photo credit: TPWD)
About Aquatic Native Plant NurseriesThe discussion around native plants and restoring them is oftentimes focused on terrestrial plants, but the nursery network in Texas prioritizes native aquatic plants to bolster the state’s fisheries and waterways.
“Native plant communities are those species in a general area that are natural and originated from that location,” said Michael Homer, TPWD Habitat and Angler Access Program Coordinator.
As each nursery is unique, propagating a variety of species, transplanting and successfully reestablishing the plants requires meticulous restoration planning.
The process starts by identifying objectives, methods, and a schedule for each site including deciding which plant species will be used and how.
Next is sourcing the plants. “If they can be collected from a local site and propagated at the nursery, that allows for local ecotypes to be used for projects. However, some plants may not be readily available to collect and propagate, so purchasing them from a private vendor may also be another option to bolster the nursery,” Homer said.
Growing the plants can take several months with planting generally targeted for mid-spring when they are taken from the nursery in pots and hauled to specific sites in and around the lake or reservoir. The growth and spread of plants depends on factors like substrate, length of growing season, available nutrients and animal herbivory. Establishment is not always successful or easy and must be monitored at every step along the way.
The Marshall Inland Fisheries crew planting cutgrass on a shallow shelf that historically had abundant cutgrass. (Photo credit: TPWD)
Boosting Biodiversity and the Ecosystem
One of the primary reasons for needing native aquatic plant restoration is the natural aging process that happens to reservoirs over time. There’s degradation of habitat features like the breakdown of woodland, and depletion of vegetation and structure from sedimentation.
Fisheries managers are challenged with mitigating the loss of these habitats by integrating additional structure and re-establishing native plants. Without these efforts fish communities experience a noticeable reduction in population numbers.
Lake Murvaul where Quintin Dean manages the HAAP nursery program is a prime example.
Since its construction in 1958, Lake Murvaul has been a popular fishery for Largemouth Bass, Crappie and Channel Catfish. The ample vegetation in the lake could sustain the coverage needed for bait fish and other macroinvertebrates that are essential to the fishery food chain.
“If the vegetation is good, the fishing is good,” said Dean.
All of that changed after several large-scale events at Lake Murvaul over the last few decades. A major drought followed by aggressive efforts to eradicate a giant salvinia invasion with herbicide treatments that decimated emergent plant species resulted in a significant decline in the fishery.
Reservoir habitats are especially difficult to manage because they are not a natural system and created by the construction of a dam.“Reservoirs typically have un-natural flow regimes and are susceptible to rapid water level changes caused by flood control or municipal water supply. It is often difficult to establish strong, diverse native plant communities. Reservoirs create a system that may not fit the life history needs of many species of plants, fish, and wildlife. Therefore, our task of creating quality fishing for the people of Texas by creating quality fish habitat is difficult in most reservoirs,” said Dean.
The large-scale loss of vegetated habitat at Lake Murvaul and the trickle-down impact on the once robust fishery is what made it a priority for restoration efforts. With the aquatic plant nursery on-site, the lake now has a chance to reestablish a self-sustaining plant community.
Eelgrass is one of the native plant species used at Lake Murvaul transplanted to grow cages where they can naturally expand. (Photo credit: TPWD)
Lake Murvaul Habitat Restoration
The aquatic plant nursery at Lake Murvaul consists of 12 tanks operating along the lake’s shoreline. Water is pumped from the reservoir into a 1,000-gallon cistern, where water is gravity fed into the 300-gallon nursery tanks. Water levels in each tank are adjusted to accommodate the conditions required for different plant species.
“Our focus is primarily emergent species due to their historic presence,” said Dean. “We have planted cutgrass, bull rush, common rush, pickerelweed, American lotus, white water lily, eelgrass, bull tongue, water willow, cattail, maiden cane, American pondweed, bald cypress and coontail,” said Dean.
When plants mature, they are transferred to grow cages that are designed to protect the founder colonies against herbivory and placed strategically along the shoreline.
“Planting sites are focused on areas where emergent species were abundant in 2016 or shallow, shoreline adjacent areas that are undeveloped and have suitable soil and depth,” said Dean. “So far, we have installed 30 cages and planted probably double without any protection.”
The Marshall Inland Fisheries crew loading up potted cutgrass to plant on lake Murvaul. From left: Quintin Dean, Jacob Green, Joshua DeWyse. (Photo credit: TPWD)
Lake Murvaul also serves as an important case study for the management of invasive aquatic species. As herbicide overspray was a major driver to the loss of native aquatic vegetation to the lake, alternative efforts are now in place to manage invasive species.
“TPWD continues herbicide treatments only when needed and occurs in areas where the native plant community will not be affected. The lesson learned on Lake Murvaul continues to affect our method of giant salvinia and other aquatic invasive species across the state,” said Dean.
The broodstock of the nursery plants that thrive are used to grow more that will eventually be planted along the lakeshore. The goal at Lake Murvaul is to restore 500 acres worth of native vegetation, successful establishment requires years of trial and error along with patience and research. Reaching that goal will happen through the introduction of plant communities and letting nature do the rest through seed dispersal and expansion.
As the plants spread naturally and vegetation and habitat improve, so too will the prey base and potentially the restoration of the trophy bass fishery.
Water willow is a common native aquatic plant used in the HAAP nurseries program. (Photo credit: TPWD)
Multi-species Plant Communities
The Lake Conroe Native Plant Restoration Program is another example of how propagating a variety of species into native plant communities works for habitat restoration.
Lake Conroe is a partner site that was started in the mid-90’s by the Lewisville Aquatic Ecosystem Research Facility and the Seven Coves Bass Club. It is now operated by the San Jacinto River Authority with a nursery that grows a combination of emergent plants, floating-leaved plants and submerged species, that are specific to the needs of this lake.
“The importance of installing native plants on Lake Conroe is to provide habitat for the fishery. It also helps to reduce erosion problems that may occur with the absence of any vegetation out there and it also occupies a niche that otherwise might be open for plants such as hydrilla which is an invasive species that we don't want in Lake Conroe,” said Lynde Dodd, Research Scientist at Lewisville Aquatic Ecosystem Research Facility.
Lake Conroe in Texas benefitting from the reestablishment of native aquatic plant species. (Photo credit: Anietra Hamper)
Emergent plants are important because of their ability to grow tall and handle the fluctuations in water levels that are common at Lake Conroe. These plants are used mainly at the shoreline. Water willow is one of the key emergent species grown at the Lake Conroe nursery.
“It’s one of our workhorse species,” said Dodd. “One of the things that we really like about water willow is it can handle being inundated; it will elongate its stems to be able to reach the water's surface. It will handle periods of desiccation, and it can handle being nibbled on by deer or crayfish or carp.”
Floating-leaved plants, like the American water lily, are another species grown at the nursery. This variety has roots that are anchored in the sediment at the bottom of the lake with leaves and flowers that float on the surface. Floating-leaved plants can be used in a range of water levels from one-foot to over six-feet. The American water lily is ideal to establish in Lake Conroe because it provides a different kind of habitat structure from the emergent species with the added aesthetics of its iconic white flower.
“This plant is rooted into the sediment, and it sends up lily pads,” said Dodd. “They have mature root bound roots coming out the bottom able to withstand the adverse conditions of Lake Conroe. This species makes a rhizome that can handle complete desiccation for short periods of time which is perfect for this lake.”
The third type of plant grown in the nursery is a submerged species that is used in water depths from two-to-six feet. A submerged species has roots that are in the sediment with blades or leaves that grow upwards and stay just below the water's surface. Wild celery is the native species selected for Lake Conroe because it is mostly resistant to herbivore damage, and it is quick spreading due to its cloning ability.
These varieties of native plants used together in communities in Lake Conroe provide habitat restoration and resilience to invasive species.
A HAAP project partner looking at coverage of native plants protected with cages. (Photo credit: TPWD)
Conservation Partners
The efforts to develop, maintain and execute an aquatic native plant nursery and habitat restoration program requires many stakeholders and conservation partners.
Multiple entities that have a stake in the success of the HAPP program also aid in identifying new opportunities, contributing resources, increasing effectiveness and efficiency of projects, lending field support with staff and volunteers, and helping to promote awareness of the projects and fisheries issues they are addressing.
“Conservation of habitat is a complex process that requires much support from various entities. By finding like-minded partners, we are able to achieve bigger successes and make habitat more relevant to non-traditional audiences,” said Homer.
TPWD has partnered with a variety of local municipalities, bass clubs, institutions, and non-profit organizations to plan and implement the habitat restoration and enhancement projects across Texas.
Lake Conroe is an example of how conservation partners make a difference in the success of the program. Since 2006 teams at the lake have transferred more than 2,500 nursery-grown plants, expanded more than 1,800 acres of native vegetation, controlled 2,000 acres of invasive species and conducted more than five miles of shoreline plantings. This success translates into the addition of structural fish habitat and the establishment of youth and community education programs.
“I can’t stress the importance of the partnerships between Texas Parks and Wildlife, San Jacinto River Authority and the Lewisville Aquatic Ecosystem Research Facility and the seven coast bass club. Without the help of the bass club or just the partnership in general a lot of the work, well, most of the work wouldn’t get done,” said Dodd.
Plant nursery tanks along the shoreline at Lake Murvaul. (Photo credit: TPWD)
The TPWD and their partners have raised and planted over 20 beneficial native plant species across Texas in at least 57 lakes since 2005 with the goal to add more as needed. Though the partnerships are collaborative, every person involved is personally impacted by their own efforts to restore native aquatic plant life to Texas waterways.
“With healthy habitats, we hope to have thriving fisheries for years to come,” said Homer. “We all have a responsibility to take care of our planet. Getting involved allows me to be a good steward, experience and connect with nature, and learn more about the world around me.”
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Author Anietra Hamper is an award-winning outdoor writer, author and lifelong angler who specializes in outdoor adventure and fishing for some of the largest species around the world. Having spent a career as a top-rated television news Anchor and investigative reporter, Anietra brings credibility to the stories she covers with her "boots-on-the-ground" journalistic approach. Anietra is based in Gahanna, Ohio.