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Dolphins,
Porpoises, and Whales: 1994-1998 Action Plan for the
Conservation of Cetaceans
Compiled by Randall R. Reeves, Stephen Leatherwood,
and the IUCN/SSC Cetacean Specialist Group, 1994, 92
pp., GBP 13.50, U.S. $20.00. Available from the IUCN
Publications Services Unit, 219 Huntingdon Road, Cambridge
CB3 0DL, United Kingdom or in the United States and
Canada from Island Press, Box 7, Covelo, California
95428, U.S.A.
Introduction
The challenge before the Cetacean Specialist Group
(CSG), and indeed before most of the IUCN/SSC specialist
groups, was well defined by Katona in his discussion
of planning for the recovery of humpback whale populations:
... management of the humpback whale or of any
endangered species cannot be regarded as a task to complete.
While there may be some actions that need to be accomplished
only once, for example designating certain locations
as sanctuaries for the species, other actions may need
to be overseen or repeated forever, or until a decision
is taken that the species should not be protected.
It can still be stated that humans have not caused
the extinction of any cetacean species. However, this
is a tentative and somewhat hollow claim. Surviving
wild populations of at least four species (baiji, vaquita,
northern right whale, and bhulan) are in the low to
mid-hundreds, and in the cases of the baiji and the
vaquita, a declining trend is thought to be continuing.
Some populations of other species have been exterminated
or very greatly depleted, e.g. the Atlantic gray whale
(extinct) and the eastern spinner dolphin in the Pacific
(reduced to about a third of its population size in
the 1950s).
Conservationists and scientists campaigned for many
years to bring the direct exploitation of large cetaceans
under effective control, largely by changing the policies
of the International Whaling Commission (IWC). Right
whales and bowheads have been protected from commercial
whaling under international law since 1935 (although
with some well-known violations), gray whales since
1946, humpbacks and blue whales since the mid-1960s.
The worldwide moratorium on commercial whaling, which
took effect beginning in 1986, can be seen as the most
recent in a long line of protective measures.
There is now reason for cautious optimism about the
status and future of certain populations of large whales.
For example, right whales in the South Atlantic, humpbacks
off Australia, gray whales in the eastern North Pacific,
and possibly blue whales in the eastern North Pacific
have shown signs of steady recovery under protection.
Some stocks, however, such as those of right whales
in the North Pacific, bowheads in the North Atlantic,
and blue and fin whales in the Southern Ocean, apparently
remain dangerously small, and there is no reason to
be complacent about their future. The lack of adequate
monitoring makes it impossible to investigate trends
in these stocks. In the 1980s and early 1990s, direct
exploitation has not posed an immediate threat to most
endangered whale populations, but accidental mortality
in fishing gear, reduction of prey due to competitive
harvesting by humans, and pollution have emerged as
potential threats that give cause for continuing concern.
There is still much interest in the conservation of
the great whales. The high public profile of commercial
whaling ensures that governments, non-governmental organizations
(NGOs), and inter-governmental organizations (IGOs)
will continue to apply pressure on the whaling nations
to eliminate whaling altogether or to keep harvests
within sustainable limits and protect at least some
populations. The CSG membership has always been well
represented in the IWCs Scientific Committee as
well as in many of the relevant governmental agencies,
NGOs, and other IGOs. Many members therefore have been
involved directly in the work of developing an effective
regime for large-whale conservation.
The first CSG Action Plan deliberately redirected the
attentions and energies of conservationists from the
commercially exploited great whales to the smaller cetaceans,
and the present Action Plan continues the emphasis on
river dolphins and coastal populations of marine species.
With the possible exception of the northern right whale,
these groups encompass the most critically endangered
species whose exceptional vulnerability is often tied
to a geographically restricted range, a relatively narrow
ecological niche, and a dependence on resources that
are also used by humans.
The survival of river dolphins depends on the health
of major river systems in less developed countries.
These dolphins are in direct competition with humans
for the necessities of life: food and fresh water. Whether
it is to control flooding, support irrigation, or produce
electrical power, the impetus for dams, barrages, embankments,
and other river modifications grows relentlessly. These
structures fragment populations of dolphins and their
prey and reduce the amount of suitable habitat available
to them. Moreover, the drive toward economic development
through industrialization, coupled with rapid growth
in human populations, has meant that rivers must absorb
ever-increasing amounts of waste products, while at
the same time they are expected to produce larger and
larger quantities of fish, crustaceans, and mollusks
for human consumption. Although river dolphins in many
areas enjoy religious, customary, or legal protection
from hunting, they face many threats, for example from
accidental fouling in fishing nets and hooks, collisions
with powered vessels, underwater detonations, and polluted
or diminished food supplies. In some areas, directed
takes (i.e. those where the cetacean was the fishermans
or hunters intended target) continue to occur,
and there is a demand for river-dolphin products such
as meat, oil, and reproductive organs.
Coastal small cetaceans are also perceived as competing
with humans for certain resources, often with no direct
evidence to support such perceptions. Some populations
have experienced high rates of mortality due to accidental
entanglement in fishing gear, and in areas such as Peru,
Sri Lanka, and the Philippines, the bycatch has given
rise to a directed catch as fishermen have become more
aware of markets for cetacean meat, blubber, and organs.
Culling operations, inspired by the perception that
depredations by small cetaceans are responsible for
local declines in fish harvests, continued at least
until 1991 in Japan and may continue in the Philippines
and Turkey.
Reprinted from 1994-1998 Action Plan for the Conservation
of Cetaceans: Dolphins, Porpoises, and Whales.
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