About This Project

Aquatic insects begin life as larvae in the water, growing and gathering resources before they emerge as adults on land to reproduce. This transition between water and land links the two habitats, as the adult insects become food for bats, birds, and reptiles. When aquatic habitats are stressed, as by contaminants, this link can be broken by way of reduced insect emergence to land. Our goal is to find out what happens to these insects when agricultural contaminants get into the water.

Ask the Scientists

What is the context of this research?

Pesticides, fertilizers, and metals have become synonymous with modern agriculture in the last several decades. Today, these chemicals are widely used and often introduced to freshwater systems like lakes, rivers, and wetlands following soil disturbance and rainfall. In the water, such contaminants can disrupt aquatic ecosystems by altering resources or reducing survival of insects, fish, and amphibians through direct toxicity. Aquatic insects are important both in water and on land as food for other animals. When insects are impacted by chemical stress or become contaminated through exposure, the animals that depend on them, like fish, bats, and waterfowl suffer too. Understanding these far-reaching environmental effects can help to better manage agricultural development.

What is the significance of this project?

Recent research has made great strides in increasing our understanding of these impacts, but more data is needed to grasp the full extent to which agricultural contaminants influence aquatic systems. This project adds to the existing body of research in important ways, by studying community-level impacts of two common agricultural contaminants in an environmentally relevant way. Many studies of contaminants look just at one chemical in a laboratory environment using just a handful of organisms, but this project takes a controlled outdoor approach. We will be introducing known levels of contaminants as in lab experiment, but use a naturally colonizing mix of insects, who are exposed to changing weather and community interactions, not just an ideal living situation.

What are the goals of the project?

We want to know what happens to larval and adult aquatic insects and their surrounding ecosystem when atrazine and selenium are introduced to waterways in low levels. The goal is to understand the effects of these contaminants that are already being introduced to wetlands, lakes, and rivers across the country. Using an outdoor tank set-up for this experiment, we have the benefits of replication, control over contaminant levels, and the ability to know a lot about our small system. However, retaining realistic conditions will help us to see how these effects could scale up in wetlands and ponds. Funding will help reach our goals to have chemical analyses and lab work completed by January 2017, with final results by spring 2017.