Fish secrete compounds in their mucus, and when you scrape mucus off a fish, we can analyze it to discover a whole host of things about that fish. You can look at genes, proteins, metabolites and hormones! Using that you can tell if a fish is stressed in general or diving into specific genes what they might be stressed by.

Working with fish mucus is part of a much broader endeavor at IISD-ELA to use more non-lethal sampling methods when we are testing fish health and fish populations. This means we have much less of an impact on the fish populations as a whole and ensure we inflict minimal harm on the fish in our lakes.