Tile Drains in the Prairie potholes

Collaborators: Jake Kerby (USD), Drew Davis (PhD 2018), Brianna Henry (MS 2018), Jerry Warmbold (MS 2016)

The Prairie Potholes are a critical sanctuary for wildlife, including amphibians and migrating birds. They are true oases in an agricultural landscape.

We’re studying the effects of agricultural runoff (through tile-drains or surface runoff) on water quality and wildlife. Our lab is specifically interested in the effects of pollution on the emergence of aquatic insects. Emerging aquatic insects can form up to 90% of the diet of ducklings, making them a key source of food for economically important wildlife species, along with numerous other birds, spiders, lizards, bats and other wildlife.

In addition to reducing emergence altogether, contaminants such as selenium may also become incorporated into the body tissues of insects. We’re measuring this potential flux of selenium from the water to land by examining the concentration this element in adult aquatic insects.

 

Contaminants and subsidies

Collaborators: David Walters (USGS), Will Clements (Colorado State University), Travis Schmidt (USGS), Bob Zuellig (USGS), Johanna Kraus (USGS), Rich Wanty (USGS), Craig Stricker (USGS), Brianna Henry (USD/USGS), Jake Kerby (USD).

When insects emerge from streams and lakes, they provide energy subsidies to terrestrial food webs. As a result, subsidy theory largely assumes that the response of terrestrial predators is driven by the quantity of the subsidy (i.e. emerging insects). But emerging insects are more than a “quick meal.” Some may also be toxic, containing metals like mercury, zinc, and cadmium. Their toxicity is determined by a suite of factors: metamorphosis, species, metal bioavailability, geologic history. We study how these factors influence the trophic transfer of metals from stream to terrestrial food webs.