THE POTENTIAL OF UNDERWATER IMAGERY FOR THE CHARACTERIZATION OF NEOTROPICAL FRESHWATER FISH COMMUNITIES

With freshwater ecosystems among the most threatened globally, the need for a low-cost, low-effort, large-scale survey tool has never been more present. Underwater imagery is a promising tool that could expand the scope of monitoring programs, yet its efficiency has mostly been demonstrated in marine environments, with comparatively less research in freshwater systems. This research aims to evaluate the reliability of underwater videos for the characterization of neotropical freshwater fish communities, i.e., to estimate fish abundance and community composition and to collect simple morphological trait data. To do so, we will compare community and trait data collected with underwater videos to data obtained from more “traditional” sampling methods: minnow traps and ex situ fish photographs. A secondary goal of this study is to test whether this method can detect changes in fish communities across environmental gradients that drive fish community composition in streams. Sampling had two components: a temporal part tracking seasonal variations of a single rivers fish community, and a spatial part comparing fish communities across sites with differing abiotic parameters expected to shape fish assemblages. Fieldwork took place in the Stann Creek District of Belize, where the selected streams were sampled from November 2024 to May 2025. Overall, this study adds to a growing body of literature evaluating the optimal conditions for underwater imagery to be applicable in freshwater and may guide the deployment of biodiversity monitoring programs and citizen science initiatives.

Presentation Preference: Standard Oral (12 Minutes)

Primary Presenter: Maryanne Doyon, Université du Québec à Trois-Rivières (maryanne.doyon@uqtr.ca)

Authors:

Maryanne Doyon, Université du Québec à Trois-Rivières  (maryanne.doyon@uqtr.ca)

Vincent Fugère, Université du Québec à Trois-Rivières  (vincent.fugere@uqtr.ca)