Loading...
Sailfish Habitat Utilization and Vertical Movements in the Southern Gulf of Mexico and Florida Straits
Kerstetter, David W. Bayse, Shannon M. Fenton, Jenny L. Graves, John
Kerstetter, David W.
Bayse, Shannon M.
Fenton, Jenny L.
Graves, John
Abstract
Pop-up satellite archival tags (PSATs) were deployed on 19 sailfish Istiophorus platypterus captured in the southern Gulf of Mexico and Florida Straits between 2005 and 2007 on commercial pelagic longline gear (n = 18) and recreational rod-and-reel gear (n = 1). The data from three tags indicated mortality events and were excluded from subsequent analyses. All PSATs were programmed to collect pressure (depth), temperature, and light-level data for 10 d at approximately 90-s intervals. These transmitted point data subsequently allowed the reconstruction of vertical movement patterns. The remaining 16 PSAT data sets indicate that sailfish are primarily associated with the upper surface waters within the top 20m(75.7% of total time during the day versus 46.7% at night) but undertake numerous short-duration vertical movements below the local mixed layer to depths of 50-150 m, presumably to feed. Analyses of 2,279 individual vertical movements among all 16 tagged sailfish indicated two distinct types (short-duration "V" and longer-duration "U" movements) similar to those reported for white marlin Kajikia albida. Sailfish also exhibited movement type differences between diel periods (having higher proportions of V movements in daytime), suggesting directed foraging at depth. Although short-duration movement to depths by these tagged fish contribute a small percentage of the total time at depth, these depths overlap with themonitored shallow-set pelagic longline gear depths actively targeting swordfish by the vessel in the local fishery. These results suggest that time-at-depth histograms alone may be insufficient to capture feeding motivations at depth and, therefore, true interaction potentials between individual sailfish and pelagic longline gear.
Description
Date
2011-01-01
Journal Title
Journal ISSN
Volume Title
Publisher
Collections
Download Dataset
Files
Loading...
sailfish.pdf
Adobe PDF, 847.28 KB
Rights Holder
Usage License
Embargo
Research Projects
Organizational Units
Journal Issue
Keywords
Fisheries Science Peer-Reviewed Articles, PELAGIC LONGLINE GEAR; MARLIN MAKAIRA-NIGRICANS; WESTERN NORTH-ATLANTIC; BLUE MARLIN; ISTIOPHORUS-PLATYPTERUS; POSTRELEASE SURVIVAL; TETRAPTURUS-AUDAX; SATELLITE TAGS; DEPTH; TELEMETRY
Citation
David W. Kerstetter , Shannon M. Bayse , Jenny L. Fenton & John E. Graves
(2011) Sailfish Habitat Utilization and Vertical Movements in the Southern Gulf of Mexico and
Florida Straits, Marine and Coastal Fisheries, 3:1, 353-365, DOI: 10.1080/19425120.2011.623990
Advisor
Department
Virginia Institute of Marine Science
DOI
https://doi.org/10.1080/19425120.2011.623990