Dolphins, Porpoises, and Whales - IUCN

vessels, underwater detonations, and polluted or diminished
food supplies. In some areas, directed takes (i.e.
those where the cetacean was the fisherman's or hunter's
intended target) continue to occur, and there is a demand
for river-dolphin products such as meat, oil, and reproductive
organs (Reeves et al. 1993a, da Silva and
Marmontel 1994).
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
(Read et al. 1988, Van Waerebeek and Reyes in press),
Sri Lanka (Leatherwood and Reeves 1989), and the
Philippines (Leatherwood e/a/. 1992, Dolar et a/. 1994,
Dolar in press ), 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 (Kasuya
1985b, Anonymous 1992a, Kishiro and Kasuya 1993) and
may continue in the Philippines (Leatherwood, unpubl.
data) and Turkey (Buckland et al. 1992b).
The lUCN's Red Data Book (RDB) on cetaceans
(Klinowska 1991) provides a comprehensive review of
information on each species and is current through approximately
1989-1990. In the present document under "Status
of Species and Populations" we have limited ourselves
largely to updating rather than duplicating the RDB.
Readers interested in more detailed background are
encouraged to consult the RDB, available from lUCN
Publications Services Unit, 219 Huntingdon Road,
Cambridge CB3 ODL, U.K. (£30) or in the U.S.A. and
Canada from Island Press, Box 7, Covelo, California
95428 (U.S. $55 in 1993).
In addition to the RDB, the IWC's report series provides
a wealth of information on the biology and status of
VIII
the populations of both large and small cetaceans.
Concurrent with its decision in 1982 to implement a pause
(= "moratorium") in commercial whaling (IWC 1983),
the IWC called for a "comprehensive assessment" of
whale stocks. By the end of 1993 major reviews had been
completed for minke whales in the Southern Hemisphere,
North Atlantic, and western North Pacific, fin whales in
the North Atlantic, bowheads in the Bering, Chukchi, and
Beaufort seas, and gray whales in the eastern North Pacific
(R. Gambell, pers. comm.). Detailed re-assessments of the
bowhead and gray whale stocks, as well as certain fin
(Greenland) and minke (Greenland and western North
Pacific) stocks, were planned for the 1994 IWC meeting.
The IWC's Subcommittee on Small Cetaceans has continued
its annual assessments of stocks in spite of the
Commission's ambivalence concerning its competence to
manage the exploitation of most small cetacean species.
Annual meetings of the subcommittee focus on particular
species groups or regional problems, and an effort is made
in each case to summarize the state of knowledge and identify
research and conservation needs. Special IWC volumes
have been published on the genus Cephalorhynchus
(Brownell and Donovan 1988) and the northern-hemisphere
pilot whales (genus Globicephala) (Donovan et al.
1993), and similar volumes are currently in production on
the beaked whales (family Ziphiidae), the porpoises (family
Phocoenidae), the gray whale, and the problem of
cetacean bycatches in passive nets and traps. Also of relevance
in the present context is the report prepared by the
Subcommittee on Small Cetaceans in 1991 as background
for the United Nations Conference on Environment and
Development held in Rio de Janeiro in June 1992 (IWC
1992a). This report covers "small cetacean stocks subjected
to significant directed and incidental takes" and provides,
in each case, a review of current status and a list of
research and management recommendations. It is available
from the IWC (The Red House, Station Road, Histon,
Cambridge, United Kingdom, CB4 4NP).