Gulf of Maine, Explained: Marine Biodiversity

In this edition of Gulf of Maine, Explained, GMRI Quantitative Research Associate and fishery science expert Jerelle Jesse explains marine biodiversity, and how she uses it as a research tool. She explains that marine biodiversity encompasses all living things in the ocean, from small planktonic organisms to seaweed to larger species like bluefin tuna.

Jerelle's role involves collecting data from organizations like the Maine Department of Marine Resources to calculate various metrics like species richness and species evenness to establish marine biodiversity levels in our region.

Over the last 20 years, she's identified decreasing species richness and evenness trends over that time in the region covered by the Maine-New Hampshire trawl survey. That means that in the last 20 years, we are now seeing fewer unique species in that region, as well as bigger differences in population levels between the species that we are seeing.

To understand the causes of these changes, Jerelle looked into climate change as a potential driver. By comparing water temperature trends with her biodiversity calculations, she discovered that water temperature is indeed a contributing factor to changes in marine biodiversity.

Increased marine biodiversity is reflective of a healthy marine ecosystem, which makes understanding why marine biodiversity in our region is decreasing a crucial step towards better managed marine resources.