BONEFISH TAGGING

Project Title: Tracking local and long-distance movements of bonefish

Anchor Tags – To date the conventional anchor tag-and-recapture program has resulted in more than 1,018 tagged bonefish released with an overall recapture rate of about 2.5%. The bonefish anchor tagging study has provided a wealth of information on movements, growth and mortality. Movements have ranged up to 75 miles (e.g., Biscayne Bay to north of Key West) for periods of release ranging from a few days to greater than a year. In the last year anchor tagging efforts have greatly increased under NFWF-BTU funding. Forty-one percent of all bonefish were recaptured during 2002. Most notably, more tags in the water is synonymous with more recaptures. Therefore, we are trying to increase our tagging effort so our recapture rates will increase. Please contact us if you are interested in tagging, and report any tagged bonefish that you catch. You can reach us at 305 361 4884 (Ault) or 305 361 4927 (Larkin) or email ault@rsmas.miami.edu or mlarkin@rsmas.miami.edu or call the UM Bonefish Research hotline at 888 754 7531.

Acoustic Telemetry – To date acoustic telemetry (AT) trials have proved successful and transmitter-tagged fish have been tracked at fine time (minutes) and space (50 m) scales for periods of time ranging up to two months. Real-time study of bonefish site fidelity showed direct correlations between bonefish movements and tidal behavior. Patterns of daily revisitation of certain areas spanning periods up to two months demonstrates that bonefish display strong site fidelity. Several fish were initially accounted for, but then moved out of hydrophone reception range, suggesting differential behavior patterns which may include spatio-temporal shifts in home range. Habitat utilization patterns indicate preference for shallow areas over proximal deep channels that appear to serve as conduits between productive flats.

Unfortunately, the process of acoustic telemetry tagging is inherently expensive. Each listening station costs about $1000, and each acoustic transponder tag costs in the range of $300. Successful implementation means that we have a large number of passive hydrophones arrayed along the coast and more than 30 active tagged fish in the water at any given time. At the present time we only have 7 listening stations and 11 bonefish tagged with acoustic telemetry tags. We are hoping to receive financial support in the future to expand our array of listening stations and to place more acoustic tags on a greater number of bonefish.