Dolphins, Whales and Porpoises: 2002-2010 Conservation - IUCN

Figure 25. A sperm whale lifts its flukes as it dives near
Manado Tua, a volcanic island within Bunaken Marine Park,
northern Sulawesi, Indonesia, April 1999. This observation of a
deepwater animal so close to a shoreline illustrates the
extreme habitat gradients that typify the eastern parts of
Southeast Asia, New Guinea, and the Solomon Islands.
Photo: Benjamin Kahn.
(P. Rudolph, pers. comm.); and Komodo National Park (Kahn
2000). Hunting is largely unregulated throughout most of
Indonesia, and environmental degradation proceeds unchecked.
Political instability exacerbates such problems.
This project is intended to provide better documentation
of Indonesia’s cetacean fauna and a better understanding of
the conservation issues affecting these species (cf. Rudolph
et al. 1997). Although the ultimate goal should be to contribute
to the development of a national conservation plan, it
will be necessary to begin with visits to sites suspected of
supporting high cetacean diversity or abundance. Information
should be obtained initially through interviews with
local people, beach and fish-market surveys, and opportunistic
vessel surveys (Aragones et al. 1997).
3. Assess the status of cetacean populations
and levels of incidental mortality in the
Philippines
There has been a tremendous increase in knowledge about
cetaceans in Philippine waters in recent years (Figure 26).
Much of the motivation for conducting research in this
region came from concern about reported kills of small
cetaceans in directed fisheries and as bycatch. At fish
landing sites along the south-western end of Negros
Island, Dolar (1994) examined the carcasses of 20
Fraser’s, 18 spinner, and 12 Risso’s dolphins caught by a
fleet of around 15 drift gillnetters over a 16-day period.
Based on information from fishermen, the same author
estimated that about 2000 dolphins, primarily spinner,
pantropical spotted, and Fraser’s, were being killed each
year by a fleet of five tuna purse seiners using
fish-aggregating devices. Directed fisheries for small
cetaceans were also reported, with as many as 200–300
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dolphins taken annually in San Francisco (Perrin et al. 1996)
and smaller numbers taken for bait in shark and chambered
nautilus (Nautilus pompilius) fisheries in Palawan (Dolar et
al. 1994). Although the hunting of small cetaceans is believed
to have declined as a result of protective legislation,
monitoring has become more difficult because fishermen
are secretive in disposing of their catches (Dolar et al.
1994).
Following the recommendations of Perrin et al. (1996),
cetacean surveys were conducted in the eastern (Dolar and
Perrin 1996) and southern (Dolar et al. 1997) Sulu Sea,
and in Malampaya Sound, Palawan (Dolar et al. 2002).
This latter survey focused primarily on a small isolated
population of Irrawaddy dolphins. A more intensive investigation
of Malampaya Sound was conducted by
WWF-Philippines in 2001.
The efforts of scientists and NGOs in the Philippines
should be continued and strengthened, with the continuing
emphasis on capacity-building. Assessment of illegal
hunting and of incidental catches in tuna purse seine and
drift gillnet fisheries remains a high priority. Intensive
surveys should be conducted to assess cetacean abundance
and threats in biodiversity hotspots that already receive
conservation attention, such as the Tubbataha National Park
and World Heritage Site and adjacent Cagayan Islands.
Valuable cetacean research in these areas can often be incorporated
with other conservation activities, at little extra
cost. More extensive surveys should involve cooperation
with neighboring countries, e.g., the joint Philippines/
Malaysia survey in the Sulu Sea (Dolar et al. 1997) and a
planned Philippines/Indonesia survey in the Sulawesi Sea
(W.F. Perrin, pers.comm.). Both were organized under the
auspices of the Convention on Migratory Species. The
Irrawaddy dolphin population in Malampaya Sound presents
a particular conservation challenge due to its small
size and apparent isolation (Chapter 6). Long-term
Figure 26. A melon-headed whale breaching in the Philippines,
July 1995. This species has a circumtropical distribution and
often occurs in schools of 100 or more individuals. Its biology
and status are not well known. Photo: Thomas A. Jefferson.