Fly Finder

The images in this project are insects that emerge from alpine lakes and provide an important source of energy for terrestrial ecosystems along the shore.

All of our samples were collected from lakes in California's Sierra Nevada mountain range in the USA. They are essentially squares of clear flypaper that catch any flying insects trying to pass by or land on them. We placed traps around lakes both with and without introduced predatory fish (trout), at different distances 0 to 50m from the lakeshore.

We expected fewer insects to come out of the lakes with fish. The introduced trout that live in these lakes are very strong predators of insect larvae, which has had negative effects for other consumer species (birds, frogs, dragonflies, and more…). However, no one knows how changing temperatures will affect the insect populations in these lakes, or whether warming might change the impact of trout.

To answer this question, we collected our data from lakes both with and without fish that experience a range of temperatures. Information on the types and numbers of insects on these cards will help us figure out how global warming and predator introduction interact to affect the subsidies provided by alpine lakes!