DEEPEND|RESTORE II: Trends and drivers of faunal abundance of the offshore Gulf of Mexico: narrowing the data gap in the Gulf’s largest ecosystem component

DEEPEND|RESTORE (D|R) has developed a multi-mode sampling, sensing, and
analytical program to assess trends in pelagic populations of the deep Gulf of Mexico, as well as the putative drivers of variability in these trends. With respect to population trends, the most substantive finding of this program is the sudden (within 3.5 y), severe, and sustained (> 10 y) decline in the abundance of oceanic micronekton (deep-living fishes, shrimps, and cephalopods) since the Deepwater Horizon oil spill. Micronekton are important prey for over 130 species of management concern in the Gulf. With respect to drivers, findings indicate that multivariate parameters (depth, mesoscale oceanographic features, light environment) in concert with animal behavior appear to be the primary drivers of pelagic assemblages. No natural environmental factor that correlated with observed declines was identified.

D|R has actively focused on resource management application and integration, with the most fruitful interactions occurring in six thematic areas: 1) Gulf oceanic micronekton as prey of species that are actively managed, federally protected, or targets of ongoing restoration activities; 2) provision of information for past, current, and future natural resource damage assessments; 3) quantification of Gulf oceanic biodiversity; 4) elucidation of ‘other ecosystem services’ provided by oceanic micronekton; 5) quantification of microplastic ingestion and its ecological effects in the open Gulf, and 6) capacity building for future research and resource management.