RESEARCH
Most of the work in the Keller lab is focused on aquatic invasive species. We look at a range of species and habitats and come at the issues from multiple disciplines. The following describe some of the work that has been recently completed.
Distribution and impacts of native and invasive crayfish
Crayfish are the largest freshwater invertebrates in the Great Lakes region and often act as ecosystem engineers. They are found in almost all aquatic habitats but little is known about their distribution or ecological roles. We have sampled crayfish in many ecosystems in the Chicago region, from 60’ underwater in Lake Michigan to small ponds and streams. Almost everywhere that we find crayfish we find that communities are dominated by invasive species, although there are pockets where native crayfish persist. We have ongoing experimental work looking at ways to control populations of the invasive red swamp crayfish and continue to monitor the spread of invaders through the region.
Barriers to spread of invasive species
Preventing the arrival and spread of invasive aquatic species is usually the best way to reduce their overall impacts. In the Chicago region, electric barriers have been built to prevent the spread of Asian carp species from the Mississippi River Basin into the Great Lakes. These barriers have been tested for how well they can prevent fish invasions, but little is known about how they may affect the spread of the many invertebrate invaders that could pass through. We have collaborated with Bo Polak in Loyola’s Physics Department to build a model electric barrier. We are testing the response of a range of invasive invertebrates within this barrier to determine whether it may be effective at keeping invertebrates out, or whether further measures are needed for these species.
In the future carbon dioxide may also be used as a barrier to prevent the spread of invasive species. This approach is currently being tested on fishes, and again little is known about how it may affect the spread of invertebrates. We have constructed tanks and are running avoidance trials to determine whether carbon dioxide barriers will be effective for invertebrate invaders.
Risk Assessment for invasive species
The movement of live organisms around the globe supports many industries including the pet, aquarium, live food, and ornamental plants trades. Many of the species transported, however, are released and become invasive. We have worked on developing risk assessment models that can help to identify invasive species before they are introduced. This allows managers and the trades to proactively remove species from trade to avoid the risks of invasion. Our work has shown that the use of risk assessment tools also produces economic benefits by maintaining robust trades in live organisms while reducing the costs of invasions.
Impacts of invasive species on human welfare
Invasive species alter ecosystems, and this can lead to large reductions in human welfare, particularly for people who rely upon natural resources for their livelihoods. For one case-study of this we worked with collaborators in Kashmir, India, to investigate the effects of aquatic plant invasions in Wular Lake. Many of the people living near Wular Lake are dependent upon its fisheries, supply of drinking water, and harvest vegetation to feed livestock. All of these have been negatively impacted by the new invasive plants causing increased poverty and many people to leave and seek work elsewhere.