I’m an active shark fisherman. I have been for decades. And though, over the years, I’ve caught, and helped
other anglers to catch, a wide variety of species, here in the upper
Mid-Atlantic, when you head out to do some shark fishing, you’re usually
targeting makos.
They are an exciting fish to hook into. They’re fast, often fly out of the water in
spectacular, tumbling leaps and can grow big enough to cause some serious
sweat and pain before they’re finally brought alongside.
And they’re a good-looking fish, the
embodiment of everything people first think of when they hear the word “shark;”
sleek-bodied, with a pointed snout, strong lunate tail and a mouthful of teeth
that resemble nothing so much as bent nails.
Their indigo backs fade to silver-blue sides that flash as the fish
rolls in the sunlit water, and when they roll next to the boat, they look up at
you with the flat black eye of God.
Unfortunately, our North Atlantic makos seem to be in
real trouble.
Looking back on my forty years in the fishery, it’s not hard
to see the problem coming on. Over the
years, I’ve seen the makos’ average size, abundance and season length shrink badly
enough that I stopped bringing them home in 1997. Since then, every one that we’ve caught has been
tagged and released, as part of the National
Marine Fisheries Service’s Cooperative Shark Tagging Program. This fall, I had a chance to take the
tagging process one step further, helping some researchers from Stony Brook
University implant three makos with acoustic tags as part of a multi-year
project.
For a long
time, the available data suggested that makos were faring pretty well; the
last stock assessment, conducted by the International Commission for the
Conservation of Atlantic Tunas (which, despite its name, deals with shark and
billfish issues as well) in 2012, found the stock to be healthy.
Unfortunately, that has now changed.
Based
on the results of a satellite tagging study completed last summer, a team of
scientists determined that a typical shortfin mako shark in the North Atlantic
has only a 72% chance of surviving in the ocean for one year without being
captured. That makes the likelihood of
capture, probably but not necessarily by a pelagic longline vessel, about ten
times greater than previously believed.
The head of the research team was quoted by Sport Fishing Magazine explaining why the results of the
satellite tagging study was so different from earlier tagging results.
“Traditionally, the data obtained to determine the rate of
fishing mortality, a key parameter used to help gauge the health of shark
stocks, has depended largely on fishermen self-reporting any mako sharks they
may have caught. The challenge is that
not all fishermen report the same way or some may underreport or not report
their mako shark captures at all, so the these [sic] catch data are known to be
of questionable reliability.”
The satellite tags, on the other hand, report in near
real-time, and make it obvious that a shark has been caught and killed.
ICCAT
scientists, using unrelated data sets, have also come to believe that
harvesting shortfin makos at the current rate will lead to a further decline in
the North Atlantic population, and that fishing mortality would have to be
reduced by nearly 80% to keep the stock from shrinking any more. However, such a reduction, to 1,000 metric
tons, probably wouldn’t do much to rebuild the North Atlantic’s shortfin mako population. There is only a 25% chance
that such a cut would halt overfishing and restore the stock to healthy levels
of abundance by 2040.
ICCAT is now meeting to decide what management measures should be imposed on fishermen wishing to retain shortfin mako sharks in the North
Atlantic. The ICCAT group considering
the problem has noted that
“releasing animals brought to the vessel alive could be a
potentially effective measure to reduce fishing mortality as studies indicate
post-release survival is likely to be about 70%. Following best practices to correctly handle
and release live specimens could therefore further increase post-release
survival. However, at this time the
Group does not have enough information to assess if the adoption of live
releases alone will be enough to reduce landings to 1,000 t or less and stop
further stock decline.”
“As you know, the new ICCAT population assessment for Atlantic
shortfin mako sharks (Isurus oxyrinchus)
has revealed alarming trends. In
particular, the North Atlantic population has been significantly depleted, and
overfishing continues. In order to have
a reasonable chance (54% probability) of rebuilding by 2040, catches must be
cut to zero. Accordingly, ICCAT’s
Standing Committee on Research and Statistics (SCRS) has recommended a “complete prohibition on retention” as an immediate
step to stop overfishing and begin the long recovery…
“With leadership from NMFS scientists, the SCRS Shark Working
Group has conducted Ecological Risk Assessments (in 2008 and 2012) that rank
shortfin mako high with respect to vulnerability to ICCAT fisheries. ICCAT has since banned retention of many
other shark species, while skipping makos.
Moreover, for nearly a decade, response to specific SCRS calls to cap or
reduce mako fishing mortality has been wholly inadequate.”
Anyone familiar with how things work at ICCAT knows that
scientists there rarely call for a complete prohibition on harvesting any fish
that has commercial value, so when the SCRS makes such a recommendation with
respect to North Atlantic makos, it’s a sign that tougher management measures
are desperately needed.
Despite the need, there are undoubtedly a lot of people
living on my stretch of coast who don’t want to see
such a prohibition take place. Seafood
dealers pay swordfish longliners well for their shortfin mako bycatch, and
there are plenty of offshore anglers who look forward taking some mako steaks home for
the grill. Shark tournaments are still
big local events, and generate big dollars for the
marinas and various organizations that sponsor and promote them; the money that
competitors pay for dock space, fuel, food, fishing tackle, bait and chum goes
directly to small businesses and boosts the economies of small coastal towns. Folks who profit from a fishery rarely if ever support shutting it down.
Such attitudes prevail in other nations, too, so a closure of the mako fishery will almost certainly face some level of international opposition. Thus, despite
the scientific advice, it’s not at all certain that ICCAT will act to halt
the mako’s decline. But it would be
unfortunate if it did not.
There’s a trident-shaped scar on my right
thumb, memorializing the day when a small female mako objected to my
hand passing close to her face while I was setting her free. I salute her spirit. The beauty, the strength and the
unpredictable speed of the mako are one of the recreational shark fishery's biggest attractions.
Which is reason enough to hope that ICCAT follows the
science and does the right thing.
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