There’s no getting around it — parasites are icky. But they’re also complex organisms that help control host populations and keep food webs balanced in terrestrial and aquatic ecosystems. They're also disappearing at an alarming rate, according to researchers at the University of Washington. After studying fish specimens dating as far back as 1880, the researchers found a steep decline in marine parasites in Puget Sound. The decline was strongly correlated with rising water temperature, suggesting that climate change could pose a significant threat to parasite species.

Chelsea Wood is a professor of aquatic and fishery science at the University of Washington and lead author of the study. She joins us to explain the role parasites play and what their loss could mean for different ecosystems threatened by climate change.