Post-Release Survival and Habitat Utilization of Juvenile Swordfish in the Florida Straits Recreational Fishery
62nd Annual Tuna and Billfish Conference, Lake Arrowhead, California, May 16-19, 2011
The use of pop-up satellite archival tags (PSATs) allows a researcher to overcome limitations associated with acoustic, conventional, or AT type tags. With PSATs, both data collection and retrieval are fishery-independent. Previous research techniques have provided information on longer-term movements, migrations, and behavior patterns, but there is still a need for additional tagging studies with “second generation” tags with depth and light data and increased memory that will further define the short-duration activity patterns and habitat utilization of juvenile swordfish in the North Atlantic. PSATs have been successfully used on other large pelagic fishes, but have yet to be used on juvenile swordfish.
This project will investigate four topics: the post-release survival rates of juvenile swordfish (defined as < 119 cm LJFL, the minimum domestic retention length) after being released from the recreational rod-and-reel fishery in the Florida Straits, habitat utilization of juvenile swordfish following release, an exploratory analysis of the effectiveness of minimum size and bag limits in the recreational swordfish fishery, characterization of catch composition and disposition of the catch and bycatch. High-resolution PSAT technology will be used to estimate the post-release survival of 20 individual juvenile swordfish captured with standard recreational fishing gear and techniques in the southeast Florida recreational swordfish fishery. These data will also be used to analyze behavioral interactions with the fishing gear, such as habitat utilization patterns. By combining the PSAT data with data from temperature-depth recorders (TDRs), additional information on swordfish interactions, such as effective fishing depths, will be assessed. Data gathered by the PSATs and TDRs will also be compared with other descriptions of swordfish behavior.
This study will be a collaborative effort with the local recreational swordfish fishery, utilizing local fishermen to conduct the field work. Data from this study will aid in determining better management practices in terms of the efficacy of mandatory release of undersized fish. The data from the tags will also provide experimentally-generated estimates of recreational fishing mortality that can be used in ICCAT stock assessments. Providing more robust estimates of mortality and evaluating the size limits will aid in determining if the yield per recruit and the spawning potential ratio target values are being reached.
Fenton, Jenny and Kerstetter, David W., "Post-Release Survival and Habitat Utilization of Juvenile Swordfish in the Florida Straits Recreational Fishery" (2011). Oceanography Faculty Proceedings, Presentations, Speeches, Lectures. 206.