NOAA’s Modeling, Analysis, Predictions, and Projections (MAPP) program is funding a new collaborative project between the Atlantic Oceanographic and Meteorological Laboratory (AOML) and the Southeast Fisheries Science Center (SEFSC) to understand how a changing climate might be influencing commercially important fish stocks. This project will identify key climate and oceanic processes that affect the biology and chemistry of the ocean of relevance to the coastal open ocean species in the U.S. Gulf of Mexico and South Atlantic Bight, managed by NOAA Fisheries and the regional Fishery Management Councils.
This project will involve pulling together modeling capacities between AOML and SEFSC to create the most complete picture possible of the factors influencing the fish stocks in the Gulf of Mexico and South Atlantic Bight. Both AOML and SEFSC will use their unique expertise to meet NOAA’s mission to understand and predict changes in climate, weather, and oceans, as well as the mission to conserve and manage coastal and marine ecosystems and resources.
“We have configured several high-resolution models for the Gulf of Mexico, Caribbean Sea, and South Atlantic Bight,” said AOML scientist Sang-Ki Lee. “Using these models, we have built close collaborations between our laboratory and the science center addressing key scientific questions, including the impacts of increasing ocean temperatures on coral bleaching and spawning of Atlantic bluefin tuna in the Gulf of Mexico and Caribbean Sea, impacts of El Niño and increased rainfall on plankton patterns in the Texas-Louisiana shelf, and seasonal variability in ocean carbon chemistry in the Gulf of Mexico.”
Building on the previous collaboration research works, AOML and SEFSC scientists will continue advancing these modeling efforts to support marine resources management and conservation.
Coastal migratory species, such as king mackerel, greater amberjack, red porgy, and red grouper, are key commercial and recreational species that support a billion-dollar economy. The most recent stock assessments for these species indicated that the stocks began declining in the late 2000s, which indicates either reduced population reproductivity, migration out of the management area, or both.
SEFSC scientist Mandy Karnauskas said she has seen a lot of things that cannot be explained from fishing pressure.
“Beyond seeing obvious shifts with fish migrating further north, we have seen evidence of stock productivity declining for a whole suite of related species,” said Karnauskas. “Low recruitment across the board for species with similar life histories suggest there is something going on with the physical environment.”
A stock assessment is the process of collecting, analyzing, and reporting demographic information to determine changes in the abundance of fishery stocks in response to fishing, and to predict future trends of stock abundance. The stock assessments track the age structure of the adult population to determine how many recruits, or new individuals, are expected in the future. When the actual number of recruits does not match the expected number, it reflects that something other than stock abundance is affecting the population, such as the environment or a predator species.
Surface water temperatures in the South Atlantic Bight and Gulf of Mexico have increased in the past 20 years and a number of oceanographic changes to the Loop Current and the Gulf Stream have been documented, further indicating environmental change may be a cause of stock declines.