A new study led by the University of British Columbia (UBC) has identified four high-traffic areas in the Pacific Ocean that should be considered high priority in conservation efforts focused on large pelagic fish, such as the tuna, blue marlin or swordfish. . According to experts, these areas should be part of “blue corridors” – routes where strict fisheries management measures or partial bans on industrial fishing should be applied in order to protect endangered fish communities and allow for increased habitat connectivity.
By studying the tendency of fish to return to their birthplace to reproduce – a phenomenon known as “philopatry”, and combining this information with catch distribution maps and genetic tagging and sequencing studies , scientists have identified the migration routes of 11 tuna and other species. large pelagic fish in the Pacific Ocean, and determined which areas should be prioritized for conservation efforts.
“We applied the concept of philopatry to movements gleaned from tagging studies of species such as near-threatened Pacific bluefin tuna and heavily fished yellowfin tuna, and we also combined this information with population linkages inferred from studies. genetics. This allowed us to identify tentative annual migration cycles,” explained the study’s lead author, Veronica Relano, a PhD student in fisheries management at UBC.
After analyzing the seasonal migration routes of the 11 fish species individually, the researchers overlaid them and observed that several species and populations use the same routes – two in the northeastern and central sections of the Pacific Ocean and two in the southwest and central sections. These areas should be part of blue corridors allowing large pelagic fish populations to sustain themselves and move safely between habitats.
“But before creating a protected area to support the recovery of declining fish populations, it is important to consider the body of knowledge available on the migrations and movements of different species,” said the co-author of the study, Daniel Pauly, aquatic science expert. ecosystems at UBC.
“That’s what we decided to do with this study. Our results suggest where such efforts would be most effective, but as noted in our title, the closed migration cycles we propose are tentative, and so it would be good if other researchers set out to test their validity.
The study is published in the journal Sustainability.
By Andrei Ionescu, Terre.com Personal editor