Master Naturalists Support TPWD

HCMN Volunteer Opportunity

Cindy Hobson

We volunteers from Hays County Master Naturalist (HCMN) do a lot of good here in Central Texas, working to conserve and educate others about the wildlife and plants that grow on the Texas landscape. But have you ever looked below the surface—the surface of the water, that is? Native animals and plants thrive in Texas’ many rivers and creeks. To make sure they continue to thrive, the Texas Parks and Wildlife Department (TPWD) River Studies Program operates a number of conservation initiatives from their office at the A.E. Wood State Fish Hatchery in San Marcos. 

Many Hays County Master Naturalists have assisted with sorting benthic (bottom dwelling) invertebrate samples with TPWD biologist Dr. Archis Grubh, one of our Chapter Advisors. In 2023, a new and different project was made available at the River Studies office. Under Dr. Grubh’s supervision, a large (250-gallon) river exhibit was set up with a pump system that mimics the unidirectional flow of a Texas river. Planning and design of the exhibit, which began in 2022, was supported by HCMN volunteer Chris Riggins. The immense aquarium, eight feet long, is formed of specially-designed acrylic panels that can withstand the weight and pressure of the water while remaining transparent for viewing. HCMN volunteer Dana Martensen worked to buff out scratches on the front viewing panel. Chris Riggins and Dr. Grubh set up the substrate, lighting, and filtration system, and then the exhibit was filled with fresh water and native plants and animals.

Dr. Archis Grubh (left) and Chris Riggins (right) after setting up the exhibit with substrate, lighting, and pump system.  Photo by Cindy Hobson, March 31, 2023.

The exhibit is now home to several native fish species and some native plants that enhance the habitat in the aquarium. Fish species include smaller fishes that are flow dependent during their life cycles. These include the handsome logperch pictured here.

This project is now moving into a maintenance phase, as the exhibit requires regular water changes and keeping algae cleaned off the viewing panels. HCMN trainee Monna Barin (her first name rhymes with “Donna”) has worked on this team as part of her required hours for 2023. I spoke with her recently at the River Studies office, where she had arrived to take care of the exhibit. She said, “When people think of an aquarium or “fish tank,” this isn’t it! Because the animals and plants in the aquarium are from our native Texas communities, not purchased at a store!” She carefully cleaned the acrylic viewing panels as part of her visit that day. 

There is still room on this team! We need at least one other person on the Rivers Exhibit Team to help keep the aquarium clean and healthy for the native critters that live there. This will allow more flexibility in scheduling work on the exhibit, especially when Monna and her husband take their RV out for camping trips the next few months!

Please contact me if you are interested in volunteering for this project and being part of the team. My contact information is available here on the HCMN Member Hub.

The aquarium is currently stocked with red shiners, blacktail shiners, and Texas logperch. The aquatic plant is eelgrass.

Visitor Information from the A.E. Wood Fish Hatchery website:

A. E. Wood Fish Hatchery is located in [San Marcos] central Texas along the banks of the San Marcos River. This state-of-the-art facility specializes in rearing fingerling sportfish for stocking more than 300 Texas reservoirs. The staff welcomes the public to come and visit this educational and informative facility. Hatchery tours are offered each Tuesday at 2 p.m. and Friday at 10 a.m. for groups of 10 or less. Tours for groups of 10 or more can be arranged by appointment. See map and directions