The IUCN/SSC Shark Specialist Group
Shark News 2: October 1994
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Sharks in Galapagos in peril
Merry Camhi, National Audubon Society
Sid F. Cook, Argus-Mariner Consulting Scientists
While shark populations around the world have been seriously over-
fished for some years, one of the newest threats is even more alarming
because it is taking place within the protected waters of the Galapagos
Marine Resources Reserve. On 23 June 1994, Ecuador reversed a
long-standing provision that protected the sharks of the Archipelago
from intensive commercial exploitation. From 16 January to 15 April
1995, permitted fishers will be allowed to legally fish for sharks in
Reserve waters beyond 3 mites from shore. Sea cucumbers, lobsters
and groupers will also be fished commercially. Because the Galapagos
Islands have long been an international model for the protection of
biodiversity, the implications of this move are of great concern to the
scientific and conservation communities.
Twenty seven species of chondrichthyans in nine families are
documented from the nearshore waters of the Archipelago
(Lavenberg et al. 1994; Grove & Lavenberg, in press). The islands
are one of the last places in the world to see large numbers of
hammerheads, including great (Sphyrna mokarran), smooth
(S. zygaena), and schools of scalloped hammerheads (S. lewini).
Together with 11 species of requiem sharks (F. Carcharhinidae)
these two groups are the most heavily exploited of the sharks
in Galapagos because their fins are highly prized in the fin markets
of the orient. The remaining 13 species of sharks found around the
Archipelago and three other species that may casually visit the
area are not targets of a commercial fishery at this time (Lavenburg
et al. 1994). However, they may be caught incidentally in gear set
for the target species.
Scalloped hammerhead sharks Sphyrna lewini caught
in shark net illegally set in Galapagos
Marine Reserve, Wolf (Wenman) Island, Galapagos.
© Doug Perrine.
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Protection for the marine environment
The Galapagos are recognized as a hotbed of biological diversity and
the birthplace of evolutionary science. They have been a focus of
global conservation efforts for decades. Establishment of the Galapagos
National Park in 1959, declaration as a World Heritage Site in 1971,
and as a Man and the Biosphere Reserve in 1982 provided extensive
protection to terrestrial flora and fauna and advertised Ecuador's
commitment to the preservation of these ecological treasures. In turn,
these conservation actions have served Ecuador well by encouraging
a thriving and lucrative eco-tourism industry.
Protection for the marine environment, however, did not come
until 1986, when the Galapagos Marine Resources Reserve was
established. Covering 70,000 km2, including the interior sea of the
Archipelago and out to 23 km, the GMMR is second in size only
to the Great Barrier Reef Marine Park, In addition, since 1990, all
inland waters have been declared an International Whale Sanctuary.
Other legislation prohibits the capture and trade of any sea turtle
species within Ecuadorian waters.
Although rapid growth in marine tourism and marine pollution
are taking their toll, the Charles Darwin Foundation identifies large-
scale commercial fishing as the single greatest threat to the marine
environment of Galapagos. Through their diligent work, in co-
operation with technical experts from around the world, a marine
management plan was developed and signed into law in August
1992. The management plan allows for local, traditional, and artisanal
level commercial fishing in the Reserve, but severely curtails industrial-
level fishing. Yet there has been continual pressure by national and
foreign fishing interests to legalize major commercial fisheries in
Galapagos for sharks, sea cucumbers, lobsters, and groupers.
History of illegal exploitation
Despite Reserve designation, illegal, industrial-scale fishing in
Galapagos has been rampant over the past 5 years. Clandestine shark
fisheries were discovered in 1988 and 1991: tens of thousands of
sharks were killed for the Asian fin market, at times using the strictly
protected local sea lion as bait. Local protest prompted legislation
that prohibited shark fishing within most of the Reserve, as well as the
transport and trade of fins to the mainland of Ecuador. Over the past
two years, despite the ban, dive tour operators have observed at least
100 dead hammerhead and Galapagos (Carcharhinus galapagensis)
sharks, as well as sea turtles, tangled in fishing nets. There are
anecdotal reports that the once common Galapagos and silky sharks
(C. falciformis) have declined markedly.
In 1992, an extensive illicit fishery also developed to export
protected sea cucumbers to Asia. Lobster have been subject to a
seven-year fishing moratorium to prevent their extermination and
grouper are also being depleted. Up to 80 major fishing vessels from
Japan, Taiwan, and Korean licensed to fish for tuna are illegally long-
lining for sharks and sea turtles and trading in other protected species
within the Reserve. Effective marine patrolling and enforcement of
the management plan are constrained by a lack of patrol vessels and
expertise in marine resource protection.
Fuelled by these foreign fishing interests and by the indecisiveness
of the Ecuadorian government over whether or not to lift previous
fishing bans in the Reserve, fishers mounted a protest and picketed the
Charles Darwin Research Station in June 1994. They threatened to kill
rare giant tortoises (indeed, over 80 tortoise deaths have been
confirmed on Isabela Island in 1994 alone) and to introduce non-
native species to the few remaining pristine islands, if the bans were
not lifted.
Ecuador capitulates
Yielding to this pressure, on 23 June 1994, the Ecuadorian government
lifted previous bans on the large-scale commercial fishing for sharks,
sea cucumbers, lobsters, and groupers. The new fishery regimes
undermine the integrity of the approved and biologically defensible
management plan for the Marine Reserve. According to Alfredo
Carrasco, Secretary General of the Charles Darwin Foundation, "If
adopted, this plan will allow for the piecemeal management of the
Reserve, ignoring the carefully established zoning scheme and
exploiting precisely those areas that are the most pristine and fragile."
Apparently, no catch quotas or management plan has been developed
for the new shark fishery.
Long-term impact of the fisheries
Targeted sharks, sea cucumbers, and lobsters are not the only species
at risk from the intensified fishing activities. As apex predators, the
larger shark species may play an important but still poorly
understood role in structuring the marine community in Galapagos.
These large sharks (likely targets of the new fishery) prey on sea
lions, fur seals, smaller shark species, and/or juveniles of the large
shark species. In other locales, such as off southeastern Africa, where
large sharks were heavily fished, the resulting proliferation of the
smaller sharks led to a decline in bony fishes important to local sport
and commercial fisheries.
Similarly, there is concern that the excessive exploitation of sea
cucumbers will reverberate up through other links in the marine food
chain because their larvae are a major component of the local
zooplankton. Even the terrestrial environment is being damaged by
these fisheries as mangrove is being heavily cut for boiling sea
cucumbers prior to export. Birds, such as the endemic Galapagos
penguin and flightless cormorant, who depend on the sea for their
food, could be adversely affected as well.
Sustainable exploitation of sharks and sea cucumbers have been
unattainable everywhere in the world. Failures of specific fisheries
have been well documented including the North Atlantic porbeagle
(Lamna nasus) fishery in the 1960s and the bull shark (C. leucas) of
Lake Nicaragua in the 1970s (Thorson 1985). Cook & Compagno (in
process ms) have estimated that more than 90% of the directed shark
fisheries in the 20th Century have failed and detail the factors causing
fishery failure.
The pattern of sea cucumber exploitation has been to "mine out"
one area and then simply move on to the next. Heavily fished areas
in Micronesia prior to World War II, still have not recovered. In 1994,
the Darwin Foundation requested that IUCN conduct an assessment
of sea cucumber status in Galapagos. The study concluded that sea
cucumber have already been wiped out in a number of locations and
that the ban on sea cucumber fishing in the Reserve should be
maintained. Because of this and other severe management problems
with illegal fishing, the Galapagos Marine Resources Reserve was
denied World Heritage Site status, to send a message to Ecuador to
better protect these unique resources.
Schooling scalloped hammerheads Sphyrna lewini.
Photo: Jeremy Stafford-Deitsch
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Conclusion
The short-term exploitation of Galapagos marine resources will
directly benefit less than 2% of the islands' residents. It is unclear
how much it will generate compared to Ecuador's US $50-60
million annual tourism industry. As has been demonstrated in Costa
Rica's Cocos Island and Mexico's Sea of Cortez, overfishing of
hammerheads there precipitated the loss of a booming dive trade
(Robertson 1994). In the Maldives, it is estimated that a grey reef shark
may be worth one hundred times more alive at a dive site than dead
on a fishing boat (Anderson & Ahmed 1993).
Because so little scientific data is presently available, it is difficult
to determine what, if any, sustainable level of fishing may be possible
in the Marine Reserve. To confound the problem, even if defensible
quotas could be established, monitoring of catch levels and
enforcement of fishing restrictions would be nearly impossible given
the financial constraints of fishery management agencies and the lack
of patrol vessels in Galapagos. Because these populations are so
susceptible to over-exploitation, and because effective management
is unlikely, we are strongly urging Ecuador not to open large-scale
fisheries for sharks, sea cucumbers, and lobsters in the Galapagos
Marine Resources Reserve.
Our thanks to the Charles Darwin Foundation, Jack Stein Grove,
Doug Perrine, Daniel Cerzon, and Sonny Gruber for providing
information for this article.
Literature cited
Anderson, R.C. & H. Ahmed. 1993. Shark fisheries in the Maldives.
Ministry of Fisheries and Agriculture, Maldives, and UNFAO. 76 pp.
Cook, S.F. & L.J.V. Campagno. (In process ms). The failure of shark
fisheries: implications for management in southern Africa.
Grove, J.S. & R.J. Lavenburg. In press. The fishes of the Galapagos
Islands. Stanford University Press.
Lavenburg, R.J., J.S. Grove, & J.A. Seigel. 1994. Note: Status of
fisheries for Galapagos sharks, with a checklist of known species.
Chondros 5(2): 10.
Robertson, G. 1994, Schooling hammerheads of the Galapagos:
Threatened natural treasure of the world. Ocean Realm (june): 39-41,
Thorson, T. B, 1985. Human impacts on shark populations. In: Sharks
- An Inquiry into Biology, Behavior, Fisheries, and Use (S. Cook,
editor), pp. 31-37.
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