Using Water Turbulence Models to Predict Invasive Carp Movement

Photo credit: Todd Davis, CC BY 2.0

The United States Geological Survey (USGS) is a scientific government agency spanning the disciplines of geography, geology, biology, and hydrology. Engineers at the University of Missouri (UM) recently partnered with USGS to assess an environmental threat at the intersection of the organization’s biological and hydrological interests: the spread of invasive carp throughout American river basins.

Four species of invasive carp—grass, bighead, silver, and black—constitute researchers’ target population. In the early 1960s, institutions like the U.S. Fish and Wildlife Service imported grass carp to fish farming stations as an experimental control for unwanted aquatic weed growth in wastewater, aquiculture, and retention ponds. By the next decade, intentional and accidental releases had enabled grass carp to enter open water systems and spread to more than 16 states. In subsequent years, bighead, silver, and black carp experienced similar patterns of importation and expansion into open waters.

Since the early 2000s, institutions and organizations across the country have recognized and sought to slow the spread of invasive carp. The tolerance, fecundity, size, and appetite of these species enable their rapid spread throughout American waterways. As carp spread, they jeopardize the survival of competing native plant and animal species. Commercial and local fishing operations face economic risks when habitats are overtaken by invasive fish.

The carp not only threaten water and economic ecosystems but also create safety hazards in recreational environments. Bighead and silver carp possess a powerful startle reflex that enables them to jump up to 10 feet above water when frightened. Boaters in bighead and silver carp habitats have reported injuries as a result of collisions with fish.

The partnership between USGS and UM engineers seeks to provide scientists with knowledge of invasive carp spawning practices and egg drift patterns. “We want to be able to control these fish,” says Duane Chapman, the team’s supervisory research fish biologist from USGS’s Columbia Environmental Research Center. Chapman is confident that the expertise of Binbin Wang, UM Assistant Professor of civil and environmental engineering and the university’s project representative, will enable improved forecasts of where carp live.

Wang specializes in the physics of environmental flows. He and his fellow researchers will further develop his innovative 3-dimensional turbulence modeling tools in order to locate possible invasive carp spawning areas in river habitats. Wang’s modeling generates environmental flows like river currents as three-dimensional structures, rather than traditional, oversimplified two-dimensional models that often fall short of supplying useful information for large and turbulent rivers.

The team hopes that they can use information derived from Wang’s new model to anticipate spawning locations and possibly create structures that will prevent the hatching of invasive carp, thereby providing balance to an overtaxed ecosystem.

Click here to learn more about the partnership between the United States Geological Survey and the University of Missouri. To learn more about invasive carp in American waterways, click here.