Rick Stafford, Truthout.org
December 2018
Sharks have low reproductive rates, making them especially susceptible to overfishing meaning they should be protected, not killed, especially for recreation or competition....
If we are to overcome the multitude of environmental threats that are urgently facing humankind, we need a major change in attitude, from exploiting nature as we see fit, to living as a harmonious part of nature. While shark fishing tournaments do target endangered species and will have negative effects on marine ecosystems, it is important to remember this is not an argument solely about numbers killed or “sustainability” of the shark populations, but about the greater environmental consequences of the messages it conveys.
Mako sharks killed at the South Jersey Shark Tournament in June 2017.
Just over three years ago, I was clinging to a rock in 20 meters of water,
trying to stop the current from pulling me out to sea. I peered out into the
gloom of the Pacific. Suddenly, three big dark shapes came into view, moving
in a jerky, yet somehow smooth and majestic manner. I looked directly into
the left eyes of hammerhead sharks as they swam past, maybe 10 meters from
me. I could see the gill slits, the brown skin. But most of all, what struck
me was just how big these animals are — far from the biggest sharks in the
seas, but incredibly powerfully built and solid. These are truly magnificent
creatures.
These animals (by which I mean any large shark, not just hammerheads) are at
the top of the marine food chain. They are important keystone predators that
can help structure marine ecosystems. Their role as predators can even help
with carbon dynamics, keeping carbon locked up in marine sediments, or by
controlling the amount of respiring biomass in our seas.
This graphic shows how top predators such as sharks can control
marine communities and help prevent climate change. Fewer top predators
result in an overall greater biomass of small fish and zooplankton. The
respiration of this increased biomass produces more carbon dioxide.
VIA AUTHOR, CC BY 4.0
Sharks have low reproductive rates, making them especially susceptible to overfishing. Many species targeted by shark fishing tournaments (including all thresher sharks, porbeagle and makos, three of the most commonly targeted species) are already classified as vulnerable or threatened by international conservation organizations, meaning they should be protected, not killed, especially for recreation or competition.
Ecological Consequences of Shark Fishing Tournaments
Sharks are fished recreationally and as part of fishing tournaments in many
places, including Australia and South Africa. However, it is typically the
East Coast of the US which has specific tournaments focusing solely on
sharks. These large shark fishing tournaments can have between a few dozen
to a few hundred competitors, but competitors will only land the largest of
these sharks. Smaller “bycatch” may go unreported, with reports of up to 16
sharks being “discarded” per boat. This catch-and-release can also be fatal
to sharks, especially species such as threshers, which show a high degree of
mortality after being released.
Given there are typically around 70 shark fishing tournaments per year on
the East Coast of the US, this gives an upper estimate of around 70,000
sharks that could potentially be killed solely for the purposes of
competition in this area (this is very much an upper estimate, assuming 100
competitors per tournament and 10 sharks killed, either through landing or
discard mortality, per competitor). Overall, recreational shark fishing in
the US is similar to or greater than the commercial catch — in 2014, 226,000
sharks were killed from recreational fishing, with potentially more dying as
a result of catch and release.
However, some perspective is needed here. The Pew Charitable Trust
estimates that between 63 and 273 million sharks are fished from the ocean
every year by commercial fishers, most often targeting shark fins. The
numbers are highly uncertain, partly as so much shark fishing activity is
illegal. Shark tournaments certainly kill fewer sharks than this commercial
catch; however, the numbers caught and the low number of species targeted in
relatively localized areas can still be high, especially on top of already
highly depleted populations.
Furthermore, while fecundity (the number of offspring an individual can
produce) can be difficult to measure in sharks, a common trend (which holds
true in species such as dusky smooth hounds) shows that fecundity levels off
with age (once mature, there is no further increase), but continues to
increase with size (bigger sharks produce more offspring). This means
selecting the biggest sharks may have an effect on the reproductive
potential of the species.
This change may be long-term too. In many commercial fish stocks,
evolutionary change has occurred as a result of fishing the largest
individuals, with species evolving to be smaller due to the human-induced
selective pressures of being large. While far more research would be needed
for comprehensive knowledge, social structure, mate choice and aggression
can all be influenced by body size, and fishing for the largest individuals
may have bigger consequences than was previously thought.
The Wider Conservation Implications of Shark Fishing Tournaments
While the removal of top predators from any ecosystem is a concern, the
population effects of shark fishing tournaments are clearly lower for sharks
than worldwide commercial fishing. However, the conservation implications of
these tournaments are greater than can be conveyed by mere numbers. In his
book Animate Earth, Stephan Harding puts forward the case for equality of
humans and animals, and argues that the removal of the hierarchy where
humans preside over nature should allow us far greater respect for the
natural environment. This builds on the foundations of bioethicist Peter
Singer’s work on equality in the late 1970s, in which he argued for equality
of humans and animals. While Singer’s work is an extension of human rights,
Harding’s ideas are to place us within nature, not above it, and hence
develop a deep respect for plants, animals and even microbes, in a similar
manner to many Indigenous cultures.
At present, our planet is under a multitude of human-caused threats. Climate
change, deforestation, overfishing, biodiversity loss and pollution all have
a common cause, which stems from an economic and political system which
treats the planet’s natural resources as either an unlimited all-you-can-eat
buffet, or a drain in which we can continuously pour our waste. To address
these environmental issues, we need to learn to respect nature.
Fishing sharks for prize money is the absolute antithesis of respect for
nature. It places man (and it is typically white male-dominated) as the
absolute power and pinnacle of life on Earth. Participants parade around
with their ocean kills for the ability to receive prize money to spend and
consume even more. It enforces the view that nature is there, not just to
exploit for food, but to exploit for enjoyment and financial gain.
If we are to overcome the multitude of environmental threats that are
urgently facing humankind, we need a major change in attitude, from
exploiting nature as we see fit, to living as a harmonious part of nature.
While shark fishing tournaments do target endangered species and will have
negative effects on marine ecosystems, it is important to remember this is
not an argument solely about numbers killed or “sustainability” of the shark
populations, but about the greater environmental consequences of the
messages it conveys.
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