Sharks are dying at an unprecedented rate, primarily due to fishing. Even in protected waters like the Bahamas, where shark fishing has been banned since 2011, these ocean predators are frequently seen with hooks, scars, and fishing gear attached. A recent study from UC Santa Barbara reveals that while retention bans help reduce shark mortality, they alone are not enough to prevent the decline of these vital marine species.
The Growing Threat of Overfishing
Despite their fearsome reputation, sharks have far more to fear from humans. Nearly one-third of all shark species are at risk of extinction, with fishing being the leading cause. Many sharks are accidentally caught as bycatch in commercial fisheries, often discarded but already dead or fatally injured.
Some shark species benefit from retention bans, which require fishers to release captured sharks instead of keeping them. Currently, 17 shark species are protected by such bans in tuna fisheries. However, experts warn that these measures alone cannot ensure sustainable shark populations.
How Many Sharks Die After Being Caught?
Researchers analyzed data from over 150 studies to estimate shark mortality rates. Their findings suggest:
- Smaller sharks and deep-water species suffer higher mortality rates due to extreme pressure changes.
- Threatened species, such as hammerhead and thresher sharks, are highly vulnerable.
- Mortality rates range widely, with species like smoothhound sharks experiencing 30–65% fatality after capture.
- Deep-water species, including sleeper sharks, struggle to survive the sudden shift in pressure when brought to the surface.
Are Retention Bans Enough to Save Sharks?
While policy simulations show that retention bans can reduce shark deaths by threefold, they do not fully address the issue. Heavily fished species like mako and silky sharks still face unsustainable population declines.
“Retention bans are a good first step,” said lead scientist Darcy Bradley, “but we need additional strategies like fishing quotas, gear restrictions, and habitat protections to truly safeguard shark populations.”
A Multi-Faceted Approach to Shark Conservation
To effectively protect sharks, experts recommend:
✔ Banning steel wire on longlines to reduce incidental shark catch.
✔ Establishing marine protected areas for shark nurseries and pupping grounds.
✔ Setting catch quotas to regulate the number of sharks caught in commercial fisheries.
Beyond Sharks: Protecting Other Marine Species
This study also highlights the lack of data on other cartilaginous fish, such as skates, rays, and chimaeras. With 57% of these species threatened with extinction, researchers emphasize the urgent need for more studies and conservation efforts.
Experts from The Nature Conservancy are now working with the Inter-American Tropical Tuna Commission to develop more comprehensive solutions for shark conservation.
Final Thoughts
Sharks play a critical role in maintaining healthy ocean ecosystems. Without stronger conservation efforts, their numbers will continue to decline, leading to severe ecological imbalances. Retention bans are helpful, but they must be part of a broader, science-driven strategy to ensure the survival of these essential marine predators.
Read the Full Study:
📖 Leonardo Manir Feitosa et al., Retention Bans Are Beneficial but Insufficient to Stop Shark Overfishing, Fish and Fisheries (2025). DOI: 10.1111/faf.12892