A study published in the Science journal reveals that overfishing has reduced the population of sharks and rays by half since 1970
Over one-third of chondrichthyan fishes— sharks, rays and chimaeras, are at exceptionally high risk of extinction due to overexploitation by target fisheries, incidental capture (bycatch), habitat degradation, climate change and pollution.
The consequences of this population decline were determined by a team of researchers who developed an aquatic Red List Index (RLI). This new RLI for sharks and rays will guide conservation action in the ocean by identifying species and places at risk and helping track the progress towards ocean biodiversity and sustainability goals.
However, amidst this concerning revelation, there is still hope. IUCN along with the SSC Shark Specialist Group has developed an innovative approach to identify ‘discrete, three-dimensional portions of habitat’ that are critical for one or more species of sharks and rays and hold the potential to be managed for conservation.
Known as Important Shark and Ray Areas (ISRAs), the initiative collects and analyses vast datasets to identify shark and ray hotspots with the goal to attract the attention of policy and decision makers. Thus far, 256 ISRAs have been identified through workshops across the Central and South American Pacific, Mediterranean and Black Seas and Western Indian Ocean Regions.
Likewise, the study published in the Science journal also highlights progress in the conservation of chondrichthyans in Australia, Canada, New Zealand, United States and parts of Europe and South Africa. Despite this, there has been a 19% increase in the risk of extinction for chondrichthyans which is a cause of concern as these widespread declines have a significant impact on other species and aquatic ecosystems.
While the extinction risk remains particularly high in countries with large coastal human populations. In contrast, the risk is lower in countries with larger economies, stronger governance and beneficial fisheries subsidies. To prevent further depletion, safeguard population connectivity and maintain top-down predator control, it is essential to restrict fishing and trade to sustainable levels.
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Link to the study: https://www.science.org/doi/10.1126/science.adn1477
Learn more about ISRAs: Important Shark and Ray Areas - a IUCN/SSC SSG project
