Fishing for fun, even “catch and release” fishing, can sometimes have a significant impact on fish species of conservation concern.

When most environmentalists think about the impacts of fishing, they’re thinking about large-scale industrial commercial fisheries. These impacts are serious and absolutely deserve our attention, and indeed how to mitigate those impacts is the subject of my second book “Why Sustainable Seafood Matters.”
However, that doesn’t mean we should ignore the conservation impacts of recreational angling, and it doesn’t mean that people who fish for fun should be able to do whatever they want because what they do doesn’t matter. Recreational angling, even “catch and release” fishing, can cause significant conservation impacts, especially to already-threatened species.
Consider the following:
Hundreds of millions of people engage in recreational angling every year.That’s several times the number of commercial fishermen in the world, and many, many times the number of large-scale industrial commercial fishermen in the world.
Those recreational anglers catch tens of billions of fish every year. Scientists estimate that more than 10% of all total fish landings come from the recreational sector. For species of conservation concern like Gulf of Mexico red snapper, more than 1/3 of landings come from the recreational sector. And there are many species whose populations are so low that commercial fisheries are totally banned, but recreational fisheries are not. And that’s just for the recreational fisheries where we have data, because this fishing sector has much less stringent reporting requirements than the commercial fisheries sector.
The biology and life history of fish means that older, larger females produce more and healthier eggs than younger, smaller females. The difference can be quite dramatic, in one well-studied species removing a single 61 cm long mothers has the same impact on population dynamics as removing more than 200 41 cm long breeding females. Black rockfish larvae from larger mothers grew three times as quickly, and survived twice as often, as those from younger smaller females. Recreational fisheries, especially trophy fisheries (i.e., trying to catch the largest-ever-caught member of a species for prestige within the angling community) exacerbates this dynamic.
It is commonly argued that commercial fisheries cannot drive a fish species to extinction, because at a certain point there are so few fish left that it’s simply not worth the fuel costs to go catch them. For recreational angling, the economic incentives are reversed, because anglers aren’t catching fish to make a profit, they pay for the excitement and fun of going to catch the fish, and rarer species are more valauble.
It’s also important to note here that “catch and release” does not mean the fish survived. In some cases, it’s more like “catch and dump a corpse.” Some fishing techniques and gears are more likely to injure or kill a released fish than others. And some fish species are more physiologically fragile (and likely to die as a result of capture stress than others). Most species have not had their post-release mortality studied at all.
And that brings us to recreational fishing as a threat to shark populations. Recreational fishing for sharks and rays is increasing in popularity all over the world over the last few decades. It’s huge in the United States; in fact more large sharks (by which I mean not dogfish) are killed by recreational anglers in US waters than are killed by commercial fisheries. In fairness, a decline in commercial shark fisheries has contributed to this surprising discrepency, but the trend started before the sale of shark fins was banned in the United States.
Hammerhead sharks in particular are some of the most physiologically fragile fish ever studied, and are poor candidates for catch and release because they often die due to capture stress. It’s no accident that dead hammerheads keep washing up on beaches right after anglers catch and “release” them.
It’s worth briefly noting here that shore-based shark fishing is even more stressful for sharks than boat-based shark fishing. When fishing for a shark from a boat, it’s in the water until right before the angler grabs it. While in the water, the shark can breathe, and it’s organs have the buoyant support of water. In contrast, with land-based/ shore-based shark fishing, the shark is often pulled across sand (beaches) or wood/concrete (piers) before it gets to the angler. This causes abrasions, infections, and even permanent gill damage.
And while many recreational anglers are environmentally responsible and even collaborate with scientific researchers, others actively mock scientists, environmentalists, and wildlife law enforcement. During my Ph.D. research that contributed to Florida changing recreational shark fishing regulations, we documented many cases of recreational anglers not only actively ignoring fishing regulations put there to protect species, but actively discussing ways to avoid getting caught while breaking the rules.
All in all, one person fishing for fun with a rod and reel is obviously not having a major impact on fish populations. The issue is that there are hundreds of millions of people doing this, catching tens of billions of fish, often targeting rarer species and larger individuals that are vital to population dynamics. And this is all happening under a regulatory and data-gathering system that’s much more permissive than that of commerical fisheries.
I want to be clear here: as far as I know, there’s never been a case in the history of the world where a fish species became threatened *because of* recreational angling. However, many fish species are now so threatened that recreational angling can now pose a significant threat to their populations.
That has a real impact, and it’s one that we need to address.