EPOW - Ecology Picture of the Week

Hector's Dolphin (Cephalorhynchus hectori), 
South Island, New Zealand

Explanation:   Here is one of the smallest and rarest of all cetaceans ... the Hector's dolphin of New Zealand.  

Hector's dolphins grow to less than 1.4 m (4.8 feet) long, and are found only in the waters around New Zealand.  Their low, rounded, notched dorsal fin is characteristic.  

Photographing these individuals was a challenge.  Hector's dolphins seldom leap from the water like other dolphins, and hardly break the water surface when they arise to breath (like all cetaceans, they are marine mammals and must breath air). 

Despite its highly restricted distribution around New Zealand, the species seems relatively secure thanks to protection in marine sanctuaries such as around Banks Peninsula on South Island.  

Hector's dolphins are poorly studied and little is known of their biology and ecology.  They sometimes occur in groups, seem to remain in local areas rather than migrate, and seem to favor river mouths with muddy water.  
  

Information:
     Carwardine, M. 1995. Whales, dolphins, and porpoises. Harper Collins Publishers, Sydney, Australia. 256 pp.
     Leatherwood, S., and R. R. Reeves. 1983. The Sierra Club Handbook of whales and dolphins. Sierra Club Books, San Francisco, CA. 302 pp.