Recovery depends on reducing mortality and maintaining long-term protection
Across many parts of the world, shark and ray populations have declined substantially due to fishing pressure and indirect impacts from human activity.
In recent years, there has also been increasing interest in whether these populations can recover once protections are put in place.
The key question is not just whether recovery is possible—but what conditions are actually required for it to occur and persist over time.
What this study actually does
In “Recovery potential and conservation options for elasmobranchs” (Fish Biology), we reviewed evidence from 40 elasmobranch populations showing increasing abundance trends to assess what drives recovery, how fast it occurs, and how stable it is under different management conditions.
The analysis synthesizes cases where populations have shown signs of increase and evaluates the underlying drivers, including both reductions in human pressure and natural ecological processes such as predator-prey dynamics.
We also examined how different management tools—ranging from fisheries restrictions to marine protected areas—relate to observed recovery outcomes.
What the study shows
A consistent pattern emerges across recovery cases: Shark and ray population increases do occur, but they are not automatically sustained once trends begin to improve. In most documented cases, recovery is linked to specific drivers, and those drivers are often not purely related to reduced fishing pressure.
Across the populations examined, only a minority of observed increases could be directly attributed to reductions in human-caused mortality. In many other cases, increases were associated with ecological shifts such as changes in predator-prey dynamics.
This distinction matters because it shows that apparent recovery signals can arise for multiple reasons, not all of which reflect long-term population rebuilding.
Recovery is possible—but highly sensitive
One of the clearest findings is that even low levels of ongoing exploitation can prevent recovery from continuing. In several populations that were showing positive trends under management, relatively small fishing mortality rates were enough to slow or reverse gains. This suggests that recovery is not just about initiating protection—it is about maintaining it consistently over time. Elasmobranchs, due to their life history characteristics, respond slowly to change, which makes them particularly sensitive to even modest levels of continued removal.
What enables recovery
Across the reviewed cases, successful or partial recoveries were most consistently associated with a combination of management actions rather than any single intervention. These included sustained reductions in fishing mortality, protection of critical habitats, and improved monitoring of population trends. In some cases, recovery was also linked to strong regulatory enforcement or near-zero mortality conditions, particularly in systems where populations had been heavily depleted. Education and awareness also played a supporting role by improving compliance and reducing direct exploitation pressure over time.
Case evidence from managed systems
Some of the strongest signals of recovery come from regions where multiple management tools were applied together. In the southeastern United States, for example, certain elasmobranch species—including sawfish and some shark species—have shown signs of increase following a combination of fisheries regulations, habitat protections, and long-term monitoring efforts.
These cases illustrate that recovery is not theoretical, but it is contingent on sustained and coordinated management actions.
Why this matters for shark and ray conservation
Sharks and rays are particularly vulnerable to overexploitation because of their slow growth, late maturity, and low reproductive rates. This means that once populations decline, rebuilding them is inherently slow, even under favourable conditions. At the same time, recovery can be disrupted relatively easily if fishing pressure resumes or if management weakens. This creates a management challenge that is less about initial intervention and more about long-term consistency.
The key insight: recovery is not a single event
This study shows that recovery should not be viewed as a simple trajectory from low to high abundance. Instead, it is a process that depends on maintaining ecological and management conditions over extended time periods. In practical terms, this means that early signs of recovery do not necessarily indicate long-term stability. Sustained protection is required to convert short-term increases into lasting population rebuilding.
Why this matters for management and policy
Effective elasmobranch recovery requires more than isolated conservation actions. It depends on integrating multiple components of management, including fisheries control, habitat protection, and ongoing monitoring systems that can detect both improvement and reversal in trends. Without these elements in place, populations can remain trapped in a state of slow or incomplete recovery. This is particularly important in data-limited systems where changes may only become visible over long timeframes.
What changes now
This work reinforces a broader shift in how we understand marine population recovery: From assuming that protection automatically leads to sustained rebound to recognizing that recovery is conditional, fragile, and highly sensitive to continued pressure.
Within this framework, monitoring becomes essential—not only to detect recovery, but to ensure that it persists.
Distributed observation systems, including those that integrate diver-based reporting and fisheries-independent data streams, can help track whether recovery trajectories are stable or being disrupted over time.
Frequently asked questions
Can sharks and rays recover from declines? Yes, but recovery is typically slow and requires sustained management.
What is the main barrier to recovery? Ongoing fishing mortality, even at relatively low levels, can prevent continued recovery.
How important is habitat protection? Very important, especially for species that rely on specific nursery or aggregation areas.
Do all populations recover in the same way? No. Recovery pathways vary depending on species, region, and management context.
What makes recovery successful? A combination of reduced mortality, habitat protection, enforcement, and long-term monitoring.
Final thought
Recovery in sharks and rays is possible—but it is not self-sustaining. It requires not only reducing pressure, but maintaining that reduction long enough for slow-growing populations to rebuild and stabilize.
Read the full study
Published in FISH BIOLOGY: Recovery potential and conservation options for elasmobranchs
