Bluefin Tuna Larvae

Full Title: Effects of nitrogen sources and plankton food-web dynamics on habitat quality for the larvae of Atlantic bluefin tuna in the Gulf of Mexico

Lead Investigator (Institution): John Lamkin (NOAA Southeast Fisheries Science Center (SEFSC)) john.lamkin@noaa.gov

Co-investigators (Institution): Trika Gerard (NOAA), Angela N. Knapp (Florida State University (Florida State University)Michael R. Landry (Scripps Inst. of Oceanography, University of California San Diego)Karen E. Selph (University of Hawaii at Manoa), and Michael R. Stukel (Florida State University)

Technical Monitor: Barbara Muhling (barbara.muhling@noaa.gov)

Award Amount: $1,613,288

Award Period: June 1, 2017 to May 31, 2020

Summary: The largest recreational fisheries in the U.S. occur in the Gulf of Mexico, including economically important species such as bluefin, skipjack, and yellowfin tuna. Atlantic bluefin tuna are highly migratory and spawn in the Gulf of Mexico, but are distributed as adults throughout the Atlantic Ocean. This migratory behavior as well as year to year changes in environmental conditions at sites where Atlantic bluefin tuna spawn makes management of the species complex. This project will investigate the impact of variability in a key nutrient, nitrogen,  on lower food webs and the resulting availability of zooplanktonic food resources for Atlantic bluefin tuna in the Gulf of Mexico ecosystem. This information will allow for improvement in Atlantic bluefin tuna stock assessments by making it possible to forecast the feeding, growth, and survival of Atlantic bluefin tuna larvae based on ocean conditions. To accomplish their objectives, they will determine the sources of nitrogen to the ecosystem and measure plankton biomass and rates of primary productivity. They will also will assess the abundance, stomach contents, feeding selectivity, age and growth rates of Atlantic bluefin tuna larvae. Overall, this project will improve our understanding of open-water ecosystems and how variations in productivity impact fish populations.