Dear Colleagues, BOEM is pleased to announce the following study, Sperm Whale Acoustic Prey Study (SWAPS). https://marinecadastre.gov/espis/#/search/study/100098 Abstract The goal of the Sperm Whale Prey Acoustic Study (SWAPS) was to characterize the prey field available to sperm whales in the Northern Gulf and assess the spatial and vertical distribution of prey in mesopelagic waters at depths between 300–800 m. BOEM partnered with the National Marine Fisheries Service, Southeast Fisheries Science Center to conducted large vessel surveys in the Northern Gulf of Mexico during summer 2009 and winter-spring 2010. Concurrent marine mammal surveys and midwater trawl sampling demonstrated strong associations between mesoscale physical features, sperm whales, and their prey. Squid from 32 taxa were collected, and 536 individuals were processed for stable isotope analysis of carbon and nitrogen. Overall, the results suggest an ontogenetic change in stable isotope values consistent with increasing trophic level of squids over the course of their life history. However, squids with mantle lengths between 31 and 150 mm were found to be the sperm whale’s dominant prey, likely because these smaller squids are more abundant and easier to capture. -- Donald (Tre) W. Glenn, III, Ph.D., P.E., CFM Senior Protected Species Biologist Consultation Specialist Professional Environmental Engineer Contracting Officer's Representative III Bureau of Ocean Energy Management (BOEM) 1201 Elmwood Park Blvd. New Orleans, Louisiana 70123 tre.glenn@boem.gov