mammals

Marine mammals
H4
The WIO has a diverse marine mammal population and several species are found in or migrate through
MPAs. Few of the existing MPAs undertake specific management of marine mammals, apart from the
dugong, but dolphins and whales are increasingly becoming tourist attractions, and in some cases are
providing important revenue for the MPA. This sheet outlines some of the management issues that need
to be considered for these species.
About 34 species of marine mammals (whales, dolphins
and the dugong) inhabit the WIO. Several species are on
the IUCN Red List, often listed as ‘Data Deficient’ (see
sheet H1) because there is insufficient information to
determine the risk of extinction. The main threats to
marine mammals are fishing-net entanglement, chemical
pollution and noise pollution.
Dugong
These were once common in many WIO countries.
Although they are listed globally as ‘Vulnerable’, their
status in the WIO is almost certainly ‘Endangered’ and
they are probably one of, if not the most, threatened large
mammal in Africa. Dugongs are particularly at risk from
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fishing, as their meat is highly valued, and from loss of
seagrass beds, their main feeding habitat. Several remaining
Dugong drowned in gill-net off Rufiji Delta near the Mafia
key locations are the focus of projects either to strengthen
Island Marine Park, Tanzania (2004).
MPAs (Kiunga Marine Reserve in Kenya, Mafia Marine Park
in Tanzania, Bazaruto National Park in Mozambique,
DOLPHINS
Moheli Marine Park in Comores and Aldabra World
Dolphins are often fished for bait for shark fishing and for
Heritage Site in Seychelles), or to create new ones (e.g.
their meat, but there is little information on their status.
Mnazi Bay-Ruvuma Estuary Marine Park in Tanzania).
Dolphin watching is a popular tourist attraction, for example
in some MPAs, including Zanzibar (Menai Bay), Kenya
(Watamu and Shimoni) and South Africa.
KEY POINTS FOR THE MPA
? Keep records of sightings of all marine mammals. They can be counted on timed boat or aerial surveys over defined
areas (appropriate survey times do not always coincide with favourable weather periods). Document specific
behaviours, such as breaching, and tail flapping, and where possible identify individuals through colour, scars on the
skin, and shape of flukes. Obtain appropriate field guides and ensure that MPA personnel are trained in identification.
? Strandings - A live stranded whale should be kept wet with sea water, and gently pushed back into deeper water,
avoiding pulling or pushing on the flippers as these can easily be damaged. A large team of people will be needed,
so call on visitors, local communities and other willing supporters.
? Whale and dolphin watching - New research is showing that marine mammals suffer high levels of stress when being
watched by tourists. It is therefore vitally important that whale and dolphin watching is carefully managed. Obtain
and/or develop codes of conduct and adhere to these. For example, when in a boat near whales and dolphins:
maintain a full-time lookout person; never approach head-on or from behind; allow the animal to approach the boat
rather than vice versa; keep engines running and do not approach animals under sail alone; maintain no-wake speed
of 2 knots (no sudden changes in speed or direction); only reverse in emergency; maintain a parallel course with the
animals; do not cut them off from open water; show extreme caution within 300-400m of the animal and never
approach within 50m (100m is a good distance for viewing feeding, but further away if animals are socialising); do
not go between a calf and adults. Involve local communities/fishers/boat operators in whale watching programmes.
? Where marine mammals occur within or adjacent to an MPA, ensure that information is made available to visitors,
local communities and key government officials about the status of, threats and biology of the particular marine
mammals. Obtain information on relevant marine mammal conservation programmes elsewhere and partner up with
relevant agencies.
? Dugong - Raise awareness amongst local communities about the status of and threats to dugongs. Encourage fishers
to report live or dead dugongs caught in nets and to use alternative gears where these exist. Avoid using an incentive
system if possible as this may encourage the capture of healthy dugongs and is likely to be difficult to maintain.
Managing Marine Protected Areas: A TOOLKIT for the Western Indian Ocean
Sheet H4

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WHALES
Sources of further information
These are seen in the WIO particularly when they are on
Arnold P. W. & Birtles R.A. 1999. Towards sustainable management of
migration. Humpback whales are regularly sighted
developing dwarf minke whale tourism industry in northern
between July and November as they migrate south through
Queensland. CRC Reef Research Centre Technical Report no. 27. CRC
the Mozambique Channel and along the east coast of
Reef Research Centre, Townsville.
Madagascar, to their Antarctic feeding grounds. They are
Carwardine, M. 2000. Whales, Dolphins and Porpoises. Dorling
also seen on their return once the southern winter sets in.
Kindersley Handbook, Kyodo Printing Co., Singapore.
Sperm whales are seen in Seychelles in July-September, and
are sometimes stranded on the northern Kenyan Coast.
Englund, A. 2001. The impact of tourism on Indo-Pacific Bottlenose
Whale populations were originally reduced drastically
dolphins (Tursiops aduncus) in Menai Bay, Zanzibar. Field Study 68,
through whaling. This has now ceased in the WIO, as a
Uppsala University, Sweden.
large part (to 40 degrees South) is included within the
Halpenny, E. 2002. Marine Ecotourism: Impacts, International
Indian Ocean Whale Sanctuary which protects whales from
Guidelines and Best Practice Case Studies. The International
exploitation. Carcasses of whales that die at sea are
Ecotourism Society. 120pp. www.ecotourism.org
occasionally washed up on beaches, and sometimes groups
IFAW, 1999. Report of the Workshop on the Socioeconomic Aspects of
or individual whales appear to beach themselves
Whale Watching, Kaikoura, New Zealand. 88pp.
deliberately. Whale-watching is a commercially important
activity in many countries, including in some MPAs.
Marsh, H. et al. 2001. The Dugong (Dugong dugon): status report and
action plans for countries and territories in its range. UNEP/IUCN
Reeves, R.R. et al. 2002. Sea Mammals of the World. Chanticleer Press.
CASE STUDY
Reeves, R.R. et al. 2002. Dolphins, Whales and Porpoises: 2002-
2010. Conservation Action Plan for the World’s Cetaceans.
Protection of the dugong in Bazaruto
IUCN/SSC Cetacean Specialist Group.
http://www.iucn.org/themes/ssc/actionplans/actionplanindex.htm
Archipelago National Park, Mozambique
Richmond, M.D. (ed.) 2002. A Field Guide to the Seashores of
The dugongs in the Bazaruto Archipelago are probably the
Eastern Africa and the Western Indian Ocean Islands.
last viable population on the East African coast but may
SIDA/SAREC/University of Dar es Salaam. 461pp.
only number about 100 individuals. The population is
Ripple, J. & Perrine, D. 1999. Manatees and Dugongs of the World.
monitored through regular aerial surveys carried out by a
Voyager Press. 131pp.
joint team of researchers from Natural History Museum in
Maputo and Texas A&M University Institute of Marine Life
Stensland, E. et al. 1998. Marine mammals in Tanzanian waters:
Sciences, and appears to be fairly stable. The National Park
urgent need for status assessment. Ambio 26(8): 771-774.
plays a major role in their protection as well as protecting
Vely, M. Les Baleines à Bosse des Iles de la Lune: petit guide pratique
seagrass bed and other key habitats, guided by the
à l’usage des observateurs. Megaptera, Association pour la
management plan, which is updated every five years.
Connaissance, l’Observation et la Conservation des Mammifères
Marine de l’Ocean Indien. 80pp. http://www.megaptera-oi.org
The main threats are incidental capture by gillnets set by
The following sites have information on strandings, responsible whale
local fishers and an illegal commercial shark fishery. Gill-
watching and other marine mammal conservation issues:
nets are banned within the National Park, but are still used
illegally because of the difficulty in patrolling the large area
Great Barrier Reef Marine Park publications on marine mammals:
(1,400 sq km). Incidental capture is being addressed by
www.gbrmpa.gov.au/corp_site/key_issues/tourism/whale_dolphin
awareness-raising through the local fishers’ associations,
_watching.html
and the fish landing sites on the islands and mainland are
Indian and South Atlantic Consortium on Humpback Whales (ISACH):
patrolled to check for dugong carcasses and meat. If meat
http://www.isach.org
is found, it is confiscated and destroyed, and dead
International Fund for Animal Welfare: http://www.ifaw.org
specimens are collected for the Museum. Those responsible
are fined and may go to court for additional legal measures
International Whaling Commission (IWC):
as appropriate. There are plans to implement a gear
http://www.doc.govt.nz/Conservation/Marine-and-
exchange programme to replace gill-nets with others, and
Coastal/International-Whaling-Commission/index.asp
to train some of the fishers in other professional skills, to
IUCN/SSC Cetacean Specialist Group and IUCN/SSC Sirenia Specialist
reduce their dependence on fishing. The rapid development
Group website http://www.iucn.org/themes/ssc: To subscribe to the
of tourism in the area provides one livelihood opportunity.
Sirenian mailing list, email: SIRENIAN@listserv.tamu.edu.
Ocean Blue Foundation: Developing an International Whale Watching
Tackling the shark fishery is more difficult as this involves
Charter: www.responsiblewhalewatching.org
illegal Chinese boats. The establishment of a small navy
base in the area and the provision of two powerful
Whale and Dolphin Conservation Society: http://www.wdcs.org
motorised boats to the Park have helped. The Park also
provides education and awareness programmes about the
need for dugong conservation to tourist operators and
local communities.
Sheet H4
Managing Marine Protected Areas: A TOOLKIT for the Western Indian Ocean

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