Critical implications for shark safety from longline fishing…
A new investigation reveals that the habitats of 3 shark species (good hammerhead, tiger, and bull sharks) are somewhat perfectly shielded from longline fishing in federal waters off the southeastern United States, but that that some key destinations are nonetheless susceptible to fishing.
The new research led by researchers at the University of Miami (UM) Rosenstiel University of Maritime and Atmospheric Science has significant implications to further guard these at-chance species from unintended fishing, recognized as bycatch, in U.S. federal waters.
Fantastic hammerhead sharks are regarded overfished and are dealing with population declines in the subtropical Atlantic Ocean and Gulf of Mexico. Tiger and bull shark populations have professional declines to a lesser extent in the area about the earlier many a long time and their populations surface to be stabilizing at current.
The exploration workforce analyzed information from 96 tagged fantastic hammerheads, tiger, and bull sharks to build habitat suitability models that reveal precise places the place these sharks are most probably to come about because of to favorable environmental circumstances. These ‘highly suitable habitats’ had been then in contrast to spots where by longline fishing equipment is at present prohibited to identify what proportion of their habitats are safeguarded from, and susceptible to, longline fishing action.
The analysis confirmed that remarkably suitable habitats overlapping with the longline fishing limited spots diverse by species and period. Highly acceptable habitats of terrific hammerheads and tiger sharks were being fairly well secured from pelagic longlines yet susceptible to base longline fishing. In addition, the two species ended up vulnerable to pelagic and bottom longline fishing off southwestern Florida. Appropriately, the researchers instructed that extending longline equipment limits to this area may perhaps profit each good hammerhead and tiger sharks species.
“This analyze highlights the importance of looking at seasonal trends in habitat use and motion designs as these can differ greatly all over the year and could impact the performance of administration designs for these species,” reported the study’s lead author Hannah Calich, a UM Rosenstiel College alumna and recent Ph.D. student at the University of Western Australia.
“Offered the extensive ranging movements of lots of migratory marine animals, the extent to which management places defend their critical habitats is frequently unknown and absolutely pretty demanding to figure out,” mentioned Neil Hammerschlag, a Research Associate Professor at UM’s Rosenstiel College and study co-writer. “We hope our strategy will be handy to researchers doing the job with other migratory species, this kind of as billfish, turtles, whales, seals, and tunas, to improved enable deal with these conservation troubles.”
The analyze, titled “Overlap concerning habitat suitability and longline gear management spots reveals vulnerable and safeguarded habitats for highly migratory sharks,” was posted on Aug. 23 in the journal Maritime Ecology Progress Series.
The study’s authors involve: Hannah Calich, Maria Estevanez and Neil Hammerschlag from the UM Rosenstiel School of Maritime and Atmospheric Science.
The investigation was supported by The Batchelor Foundation, Disney Conservation Fund, Wells Fargo, Guy Harvey Ocean Basis, and the West Coastline Inland Navigation District.
Supplies furnished by College of Miami Rosenstiel School of Marine & Atmospheric Science. Authentic created by Diana Udel. Be aware: Information may be edited for model and length.