Marine Mammals in Madagascar:

Current Knowledge and Climate Change

Salvatore Cerchio

Cetacean ConservationAnd

Research Program

Wildlife Conservation SocietyAmerican Museum of Natural

History

• Pinnipeds– 2 species (accidental)

• Sireniens– 1 species - Dugong

• Cetaceans– 7 Mysticetes, 3 confirmed– 21 Odontocetes, 12 confirmed

Marine Mammal Diversity

• Humpback Whale• Southern Right Whale• Blue Whale

– Potential overlap of 2 subspecies

• Brydes Whale, likely– Species ID uncertain

• Fin Whale, suspected• Minke Whale, suspected

Mysticetes:Baleen Whales

• Perturbation of Antarctic Ecosystem– Humpback and True Blue Whales

• Potential local effects for some species that may feed in Madagascar waters– Pygmy Blue Whale

• Perturbation of migratory patterns due to circulation and SST changes

• All SPECULATIVE

Mysticetes:Potential Impact of Climate

Change

Good data limited to two CCRP field sites:• Antongil Bay

– 3 species observed• Only Bottlenose dolphin regular/resident

• Southwest (Toliara/Anakao region)– At least 8 species observed– At least 3 can be considered regular/resident

• Indo-Pacific humpback dolphin• Bottlenose dolphin (inshore form / Indo-Pacific species?)• Spinner dolphin• (Spotted dolphin, Risso dolphin, Pilot whale…)

Odontocetes:Toothed Whales and Dolphins

• Submarine Canyon• Closest point of deep water to

coast of Madagascar• Presence of some deep water

species– Spotted dolphin– (Spinner dolphin)– Pilot whale– Risso Dolphin– Bottlenose dolphin (offshore

form)– Pygmy killer whale

• Near shore shallow water species– Humpback dolphin (obligate)– Bottlenose dolphin (inshore form)– Spinner dolphin

SW Bathymetry

Impacts on Coastal Dolphins:Hunting around Toliara and

Anakao

• Direct takes of small cetaceans in Madagsacar primarily on West Coastal regions, at least north to Mahajunga

• Best documentation in southwest

• Toliara region• Focus of work in village of

Anakoa, population of 3000-5000

• Dolphins taken for food as well as local sale

Species Direct Take “Stranding”

Spinner Dolphin 1850-2550 900-950Bottlenose Dolphin1700-1900 90-240Humpback Dolphin 20-70 30-35Unidentified dolphin 400 100

Total 3970-4920 1130-1350

Interview Data – Anakao 1999(N. Andrianarivelo)

Estimated Dolphin Mortalities 1974-1999

Anakao – Recent Dolphin Take (Y. Razafindrakoto & N.

Andrianarivelo)

October 2005

100-200 Stenella longirostris

Driven against reef and stranded

Concealed from authorities

Meat sold in villages to N and S

Excess buried

Odontocetes:Potential Impacts of Climate

Change

• Impacts on ecosystem and prey resources– Possibly more significant

for inshore species

• Bi-directional Synergies– Dolphin populations

already depleted from hunting – could be further stressed by CC reduction in prey species

– Removal of top predator – complex effect on coral reef / coastal communities also stressed by CC

• Again SPECULATIVE

Gaps in Knowledge / Future Directions

• Obvious conservation concern / emergency in SW region

• Very little known about cetacean distribution and status throughout almost all other regions

• Prelim data from Nosy Be indicate potential healthy population of coastal species

• NEED extensive surveys and baseline data collection

• NEED studies targeting potential impact of Climate Change

• NEED work within local communities to ameliorate hunting pressure and promote sustainable resource use