Deep-Pelagic Fauna

Full Title: Trends and drivers of faunal abundance of the offshore Gulf of Mexico: Narrowing the data gap in the Gulf’s largest ecosystem component

This project identifies long-term trends in fishes, shrimps, cephalopods, and other fauna in the deep-pelagic Gulf of Mexico (open ocean midwaters beyond the continental shelf, from just below the surface to just above the bottom) and provides this information to resource managers responsible for the numerous species that rely on deep-pelagic fauna as prey, including marine mammals.

The Team: Tracey Sutton (lead investigator, Nova Southeastern University, tsutton1@nova.edu), Kevin M. Boswell (Florida International University), Heather Bracken-Grissom (Florida International University), April Cook (Nova Southeastern University), Danté Fenolio (San Antonio Zoo), Tamara Frank (Nova Southeastern University), Daniel Hahn (NOAA Office of Response and Restoration) Mathew Johnston (Nova Southeastern University), Heather Judkins (University of South Florida St. Petersburg), Rosanna Boyle (née Milligan) (Nova Southeastern University), Jon Moore (Florida Atlantic University), John Quinlan (NOAA Southeast Fisheries Science Center), Isabel Romero (University of South Florida), and Michael Vecchione (NOAA National Systematics Laboratory).

Technical Monitors: Mandy Karnauskas (mandy.karnauskas@noaa.gov) and Kris Benson (kristopher.benson@noaa.gov)

Science Program Liaison: Caitlin Young (caitlin.young@noaa.gov)

Federal Program Officer: Frank Parker (frank.parker@noaa.gov)

Research Area: Multiple species

Award Amount: $2,794,147

Award Period: This project began in September 2019 and will end in May 2024.

Why it matters: The deep Gulf of Mexico is a special place – it is one of four ‘hyperdiverse’ deep-pelagic ecoregions on Earth. It is also the largest and least known habitat in the Gulf of Mexico. Much of the Gulf’s offshore diversity comes from juvenile stages of coastal fauna, including managed reef fishes, demonstrating a connection between the Gulf’s inshore and offshore waters. Deep-pelagic fauna are the main prey of the majority of marine mammal species in the Gulf, as well as other oceanic apex predators like tunas, billfishes, sharks, and seabirds. The deep-pelagic fauna is also involved in transporting carbon from surface waters to the deep ocean where it can be sequestered.

What the team is doing: This project uses midwater nets and acoustics (i.e. sound waves) to sample from the surface to roughly one mile (1500 m) deep. By analyzing the data collected, the project team quantifies abundance and biodiversity trends in space and time. In doing so, the project is developing baselines for pelagic fauna in the Gulf of Mexico, a rarity anywhere in the World Ocean. In addition, the project team analyzes sea temperature, salinity, and ocean circulation data to identify key drivers of pelagic community structure and abundance. Other project components include analysis of petrochemical contamination, genetic diversity, and animal sizes over time. DEEPEND’s taxonomic experts will produce the first comprehensive identification guide for the deep-pelagic fauna in the Gulf of Mexico, a critical need for future open-ocean resource management. 

Expected Outcome: This project will produce assessments of pelagic faunal abundance since Deepwater Horizon to support ecosystem-based management and restoration of the open-ocean Gulf.

Recent Results: Analyses of the project’s 2021 survey are still underway, but the initial synopsis is that the deep-pelagic fauna shows no clear signs of recovery from the dramatic population-level declines that occurred after Deepwater Horizon. Additionally, pelagic sampling over a deep-water coral site in the northern Gulf appears to indicate for the first time a high degree of coupling between pelagic resources and deep-benthic communities.