Monitoring Little Tunny (Euthynnus alletteratus) Movements and Post-Release Survival in Nantucket Sound, Massachusetts.

Kim, Edward¹, Caroline Collatos^1,2, Jeff Kneebone¹, ¹Anderson Cabot Center for Ocean Life, New England Aquarium, Boston, MA, ²School for the Environment, University of Massachusetts Boston, Boston, MA

The little tunny (Euthynnus alletteratus), colloquially known as false albacore among anglers, is a highly migratory tuna species that occupies coastal waters seasonally across the U.S. Atlantic Seaboard. In New England and mid-Atlantic states in particular, these fish are the target of a prominent catch-and-release recreational fishery that occurs from late summer into the fall. However, a dearth of knowledge regarding local movement patterns and post-release survival in conjunction with the current absence of a structured management plan indicate a need for dedicated studies on this species. In partnership with the American Saltwater Guides Association, 63 little tunny were captured on rod-and-reel tackle simulating the recreational fishery and tagged with internal (n = 50) or external (n = 13) Vemco V13 acoustic transmitters. Tagged fish were tracked within an array of 25 acoustic receivers deployed in Nantucket Sound between August and October 2022. Preliminary results suggest high mobility throughout the array as well as a high rate of post-release survival based on the timing and location of acoustic detections. Survival appeared to be correlated with fish condition at release, as a greater proportion of fish in good (94%) and fair (83%) condition were detected compared to those released in poor condition (33%). Future work will examine finer-scale movements within Nantucket Sound and broader movements along the U.S. east coast.