Comparing the Effects of Invasive Waterhyacinth on Aquatic Communities
Abstract
Waterhyacinth is an invasive freshwater species that rapidly grows across water bodies, creating dense mats that disrupt local ecosystems. Our goal was to measure the impact of waterhyacinth on aquatic communities. We tested the hypotheses that waterhyacinth supported different fish and invertebrate species than native aquatic plants, used more dissolved oxygen (DO), and provided different levels of support to abundant invertebrates like amphipods. The fish communities under both plant groups were collected using a 1m2 throwtrap and a backpack electrofisher. This allowed for comparison between fish communities and method efficiency. We compared invertebrate community assemblages by collecting samples of roots from both plant groups for invertebrate identification. We collected the largest 20 amphipods of each invertebrate sample, measured, and weighed them. We compared DO used by native plants and waterhyacinth in outdoor aquariums. We tested a range of plant densities at different times of day using a handheld DO meter. Fish communities did not differ among plant types. The throwtrap was more efficient overall, with more than five times as many fish obtained than the electrofisher. No significant difference was found between invertebrate communities. There was no significant difference in amphipod length between sites, but amphipods from the Pennywort sites had lower masses. DO increased during daylight hours for all plants. Waterhyacinth and pennywort used equal oxygen and higher plant density led to lower DO levels. This will provide a baseline for future studies investigating waterhyacinth management techniques and assess their success within an ecosystem.
Faculty Sponsors
Dr. J. Matthew Hoch
Project Type
Event
Location
Alvin Sherman Library
Start Date
4-3-2024 12:30 PM
End Date
4-4-2024 1:30 PM
Comparing the Effects of Invasive Waterhyacinth on Aquatic Communities
Alvin Sherman Library
Waterhyacinth is an invasive freshwater species that rapidly grows across water bodies, creating dense mats that disrupt local ecosystems. Our goal was to measure the impact of waterhyacinth on aquatic communities. We tested the hypotheses that waterhyacinth supported different fish and invertebrate species than native aquatic plants, used more dissolved oxygen (DO), and provided different levels of support to abundant invertebrates like amphipods. The fish communities under both plant groups were collected using a 1m2 throwtrap and a backpack electrofisher. This allowed for comparison between fish communities and method efficiency. We compared invertebrate community assemblages by collecting samples of roots from both plant groups for invertebrate identification. We collected the largest 20 amphipods of each invertebrate sample, measured, and weighed them. We compared DO used by native plants and waterhyacinth in outdoor aquariums. We tested a range of plant densities at different times of day using a handheld DO meter. Fish communities did not differ among plant types. The throwtrap was more efficient overall, with more than five times as many fish obtained than the electrofisher. No significant difference was found between invertebrate communities. There was no significant difference in amphipod length between sites, but amphipods from the Pennywort sites had lower masses. DO increased during daylight hours for all plants. Waterhyacinth and pennywort used equal oxygen and higher plant density led to lower DO levels. This will provide a baseline for future studies investigating waterhyacinth management techniques and assess their success within an ecosystem.
