Practical Boat Owner - January 2016

Cruising

W

hales, dolphins and porpoises are collectively known as cetaceans,
‘large sea creature’. All cetaceans are mammals and, like us, they breathe air (at stemming from the Latin ‘ceta’ meaning
the surface) using their lungs, give birth to live young and are dependent on their mother. Worldwide, there are approximately 86 species of cetacean,
ranging across every ocean – and it may come as a surprise to learn that approximately a third of these, 29 species,

Identifying ocean

GIANTS

ABOUT THE AUTHORLindis Bergland is a Marine Mammal

Advisor with the Joint Nature Conservation Committee, a public body that advises

UK Governments on nationwide and international nature conservation.

Lindis Bergland explains how to understand and identify cetaceans commonly found in UK waters wave hits an object, and the echo is intuitively interpreted by the whale. A structure using air from one of the nasal passageways (the right) evolved to
produce the clicking sounds. The other nasal passageway leads to the blowhole, which appear as a single ‘nostril’ on the head, used for breathing.
sounds, they do not create clicking sounds for echolocation and therefore have retained both their ‘nostrils’ for breathing. Although baleen whales can also make
Baleen whales do not hunt their prey in the way that toothed whales often do, and therefore do not require the echolocation skills to find and chase their
food. As the blowholes differ between the two types, the blow – produced on exhalation at the surface – can be used to identify certain species of cetaceans from
a distance. can be tricky as the observer rarely sees the whole animal. Although most species Identifying different species of cetaceans
of cetaceans are able to jump clear of the water and many sometimes do, it is more common to spot a blow in the distance or a dorsal fin popping out from the sea.
how to identify the most common cetacean species you may encounter in UK waters.This article will give some guidance on

have been recorded in UK waters.cetaceans as whales, dolphins and porpoises, the terminology is somewhat Although we commonly refer to

misleading. For example, killer whales and pilot whales both belong to the dolphin family (‘whales’, mainly due to their larger size. It Delphinidae), but are referred to as

is therefore more taxonomically correct to divide cetaceans into two types based on shared characteristics: the baleen whales (Mysticeti) and the toothed whales

(plates rather than teeth and filter their food from the water, whereas toothed whales – as the description suggests – have teeth.Odontoceti). Baleen whales have baleen

and porpoises, have the ability to use echolocation for navigation, hunting and communication. Echolocation can be All toothed whales, including dolphins

described as biological sonar, and it enables the whales to ‘see’ their environment clearly in dark or turbid waters. The whale creates clicking sounds

which send sound waves into the water column: an echo returns if the sound

US National Oceanic and Atmospheric Administration