By Winslow Taylor
Sharks tend to dominate headlines. Whether it’s the sharknado, baby shark, the Shark brand of vacuums, or shark attacks, sharks have a way of grabbing our attention. These days, not only is there “Shark Week” on the Discovery Channel, but we have great white sharks with satellite tracking tags that have their own Facebook pages.
Your perception of sharks in many ways depends on your experience on the water. To perhaps most of the world, the shark is seen as a tough, dangerous, and fearsome fish. To those who make their living on the water, the shark can be one of the most annoying and economically devastating marine creatures on the planet.
Outside of a few geographic locations, much of the sportfishing community considers sharks a nuisance that is rarely targeted for sport. Not only are sharks not targeted, most boats actively try to avoid them—in some places avoiding the damned things is something that is impossible. Not only do most captains try to get away from sharks, most folks have little understanding of how to differentiate species.
For many in the sportfishing community, shark identification goes something like this: great white (jaws), hammerhead (looks like a hammer), bull shark (eats people in less than ten feet of water—don’t fall in), mako (looks mean, caught trolling, tastes good), thresher (weird floppy tail, lives in Yankee Land and California).
Everything else is a “brown shark” or a “grey shark.” It’s not entirely fair to paint them in a negative light, but most pelagic fisherman only (again a generalization) deal with sharks in a few scenarios. The sportfishing community’s shark identification tendencies are matched by the normal scenarios that govern most encounters.
Aside from party boats and charters that make a living chumming up sharks, many interactions fall within these two scenarios…
Everyone knows this one. The feeling of the rigger popping, the anticipation, the bow in the rod, and the, “Hey did you see what that was?” This is followed by, “I don’t know but it feels nice!”
The next thing you know, the mystery fish starts fighting like a garbage bag filled with rocks. Great (sarcasm) – maybe it’s a shark. But wait, it’s not over yet! The best part is trying to figure out how to get back your $50 lure while a creature that resembles an aquatic pitbull made of sandpaper—complete with rows and rows of razor sharp teeth—spins barrel rolls boatside on the leader.
If you’re lucky all you have to do is throw on a new leader, if you aren’t lucky then then your plug and hookset is going to the bottom with that dredge your mate lost last summer.
You’re on the break and you’ve just come off plane. Some guys are paying $2,000+ to catch some meat fish (or even marlin, sailfish or swordfish).
Everything looks great—calm seas, you didn’t spill any coffee on the way out, the mate showed up on time, and there are fish are around. Within a few minutes you spot two boils behind your left flat and right short. The 50 wides go tight! It’s going to be a good day! Both anglers are fighting their fish, making headway, then all of sudden the line feels frantic……and then it’s dead weight.
Both anglers reel up mutilated tuna. At first the crowd says the usual, “That’s crazy!” or “Did you see that?!” Then the same thing happens twenty more times. At the end of the day, where you should have limited out, you return home with a handful of non-shark-bit tuna and an exhausted crew.
The sharks took a would-be epic day and traded it in for an exhausting battle of human v. shark. Not only that, but you lost at least $150 in tackle. This scenario is that much more soul-crushing when instead of mashing on a dozen tuna fish, mobs of insatiable sharks mutilate, or entirely consume, the marlin of a lifetime.
There are spots where even grander marlin are not safe. The incredible thrill of hooking the fish you have been chasing for your entire life or career is quickly then transformed into the horror and tragedy of watching the magnificent, once in a lifetime catch be gobbled up by sharks.
Fishing and Science
Whether in terms of marine ecology or the fishing side of things, sharks have their own niche.
They can be the bread and butter of the inshore half-day crowd, the folks in the northeast love to go “shaaahhkinnnn,” and mako is delicious. Certain species of shark are commercially valuable. They also perform a valuable function in the ecosystem. The 1970s and 1980s witnessed widespread overfishing that depleted shark populations in many places around the world.
With the implementation of fisheries management regulations, many shark populations have rebounded. In some places, the shark comeback has been so noticeable that sharks are decimating hook and line catches! Anglers from around the globe are having their fish eaten before their gamefish (or commercial catch) clears the gunnel.
From the Sportfishing Perspective
One area particularly hard hit by these roving gangs of sportfish eating sharks is the Outer Banks in North Carolina. When fisheries managers began shutting down commercial shark fishing, the sportfishing community experienced a drastic increase in numbers of fish being sharked.
Fisheries regulators claim that these sharks are overfished, while the folks who are making their living on the water see otherwise. Not only are the tuna getting eaten frequently, but the sharks will trash gear and cost the boat both time and money. A quick google search of “depredation fisheries” reveals a multitude of scientific articles on the subject, almost all of them from 2015 through the present day.
I spoke with Captain Rob Barker who runs the Desperado out of Pirate’s Cove. Barker echoed the sentiment of all the captains in the OBX fleet. Rob said in the past three years it’s gotten really bad. He’s had days where sharks have eaten 20-plus tuna. It’s not just in one spot either, Rob explained that it can be all along the break.
There are times where the boats are spread out for more than ten nautical miles and all the boats are losing fish to sharks. What is sometimes overlooked in all of the shark/tuna carnage, is the toll that it takes on the boat and crew. On a day where Rob would otherwise be back at the dock by lunch with a limit of tuna, instead he has lost 15 fish to sharks and scrapped together a “mediocre” day.
It takes a toll on your gear too, on one trip where the kite was producing the bites, Rob went through 15 Yummy flyers. At around $8.00 per fish that adds up real quick. When the sharks are that thick you just can’t afford to keep losing tuna—not only is it hard on the crew, it’s wasteful to the resource.
When the fleet is losing 150 tuna per day, that is not an insignificant number of fish over a season. Rob mentions that the fleet tries to be thoughtful in their game plan and target other species if the sharks are too bad. Rob, like most captains, is upfront and transparent with his clients.
He lets them know that if the sharks are too thick, they are going to go to “plan b.”
The Scientific Perspective
The issue of sharks gobbling up sportfish is not just a North Carolina problem, it’s the same story on the break from the Gulf to Florida/Bahamas up to New England. Even the folks in Australia face more than their share of this sort of thing.
On the scientific side of the spectrum I spoke with Dr. John Carlson, Ph.D. John is a biologist with NOAA in Destin, Florida whose focus is on sharks and their biology. Specifically, I spoke with John on the subject of depredation. Depredation is the term used to describe when a predator partially or completely consumes an animal caught by fishing gear before it can be retrieved to the fishing vessel.
Basically, depredation is the fancy word for sharks eating a hooked fish! The fascinating part of my discussion with John was his belief that sharks are “learning.” John mentioned that even in shark species whose numbers are declining, depredation is up in some areas.
This means that even though there may be fewer sharks, those sharks are actively learning how and where to get a “free” meal—and these instances of depredation are on the rise. One specific example was the oceanic whitetip shark. The whitetip is listed as a “threatened” species, but there are spots in the Bahamas where they will eat anything attached to a line.
Sometimes they even appear next to a boat, drawn just by a change in engine pitch. If you are spearfishing in some parts of the Bahamas, it’s almost mandatory to swim to the boat and change locations once you shoot your sling. The sharks attribute that noise to food and actively swim toward the source of the sound/vibrations.
John’s thought is the sharks have learned that low frequency sounds (such as a boat backing down) can indicate the presence of an easy meal. He did a test where they took a boat out in the Gulf and just revved the engines (they were not fishing), within 15 or 20 minutes there were sharks surrounding the boat.
It’s also believed that the shark’s sensory cells help them hone in on a hooked fish. The vibration coupled with the low frequency engine noise rings the dinner bell. Obviously, there are multitudes of professional research papers and PHD dissertations on the topic, but (1) I wanted to keep this article simple and (2) I suck at science.
When discussing this topic with John he believed the jury is still out on depredation, as even when populations are down, the depredation rate is higher. Although some years are worse than others, there is no doubt that sharks have learned how to chase an easy meal.
Without getting into a political debate on the merits of conservation and global environmental changes (that’s a nice way of saying climate change), the scientific community believes there has been a shift of some sort, but what or why that shift has occurred is still a big question mark.
It’s undisputed that shark depredation is on the rise, but its exact causes are not yet known entirely. One thing is for certain, the jury is still out on both sides of the debate.
What does all this mean?
The short answer is no one knows.
The fishing community believes the commercial shark quota should be increased, as the depredation issue is a relatively new phenomenon in many areas (in some places its timing corresponds with decreased commercial shark quota).
The scientific community (broadly speaking) believes the quota issue has little bearing on the increased depredation rates, instead shark behavior has changed and the sharks are “learning” new traits. It’s hard for the scientist to explain why the increased “learning” among species, but their data certainly supports their view.
As with most things in life, it would be hard to say that one side is entirely right and the other entirely wrong. Fishermen are on the front lines observing the changes over years, if not decades. The scientific community is excellent at analyzing data, observing the issue from a standpoint of neutrality.
The sometimes adversarial nature of the relationship between fisheries policy makers and the men and women who make their living on the water adds just another level of complexity to the issue. That being said, each side has a vested interest in preserving our resources both locally and globally.
The issue of depredation is not going disappear. A world without sharks would be bad. So would a world within which potential charters took their money elsewhere because too many sharks ate too many of the fish they were trying to catch. Solutions to the problem will likely result from the fishing community and fisheries scientists and policy makers working together.
The Argument Against Killing All of the Sharks
(Written by Elliott Stark—please do not send hate mail to Winslow…)
At first glance, the problem of sharks eating marlin, tuna, sailfish and swordfish would seem like it could be solved simply and effectively with nothing more than bang sticks, 45s or, if you wanted to get fancy, an AR15.
Sure, waxing a shark or two here and there might take some of the sting away from being sharked over and over again, but the approach taken by fisheries managers is one that is justified by the biology of sharks and their reproductive strategy. Sharks have a different life history strategy than do egg-laying broadcast spawners like tuna and billfish.
A large, mature marlin or tuna may spawn multiple times per year. At each spawning event, the fish will release hundreds of thousands or millions of eggs. While each one of these eggs statistically has a relatively small chance to survive, a good year class can result in rapid rises in populations (especially under appropriate fisheries management policies).
Under this scenario, an overfished population can rebound to a healthy stock in a relatively short amount of time. This in fact was the case with swordfish in the Atlantic—which was in really rough shape in 2001, when the Straits of Florida were closed to commercial fishing. Now, because swordfish reproduce so quickly and were managed reasonably, anglers all across the Gulf and East Coast are mashing swordfish.
Sharks, on the other hand, have a different reproductive strategy. They produce a small number of offspring, each of which is born with a high probability of survival. Giving birth to live offspring, many species of shark bypass the vulnerable egg, larva and really small juvenile stages that are necessary for fish that reproduce via broadcast spawning.
Each juvenile shark comes out ready to eat and hunt—and as long as it can stay away from its larger cousins, will likely survive. Because sharks give birth to small numbers of offspring, they can replenish their populations much more slowly than species of egg laying fish. This would make sense, especially when considering that they evolved in an unfished ecosystem.
If sharks were as productive as other species—each giving birth to millions of offspring, each of which were well equipped to survive to adulthood, the oceans might be populated by nothing but sharks. As anyone who has been around for the past 50 years might guess, the oceans are no longer an unfished ecosystem.
In an overfished population characterized by slow reproductive capacity, such as the way many shark species are managed, each reproductively mature individual is of greater importance to the population of the species. A simpler way of saying this would be, a single large female great white shark means more to the great white population than a single large blue marlin means to the blue marlin population.
That, of course, is not to mention how many people in the world love to eat shark fin soup. Something to think about….