The new species, named Balaenoptera omurai, also has an unusually- shaped head and a small number of baleen plates
. These form the sieve-like device, made from the same material as hair and fingernails, that the whales use to filter out the tiny crustacea on which they feed.
On the basis of annual oscillations in radiocarbon content along baleen plates
, Schell and Saupe (1993) estimated that the baleen grows more than 50 cm in the first year of life and then the growth rate slows markedly, e.g., to 35-45 cm in year 2 and 27.5-35 cm by year 3.
Travelling inside the whale's mouth, 3-D images show how teeth have formed huge baleen plates
which act like sieves, filtering out 70 tons of water from the throat pouch, and how the whale's tongue brushes industrial quantities of krill down its throat.
"Most huge marine creatures are so-called `filterfeeders' -- that is, they obtain their foods from the surrounding seawater by straining it through a series of baleen plates
in their jaws.
The right whale lumbers along with its mouth half open filtering out plankton, its food, through the baleen plates
. It was a simple matter for whalers to row close to a right whale and plunge a harpoon into it.
While massive in size--45 feet in length and weighing an average of 70,000 pounds--they eat only small fish and krill by using large filter-like baleen plates
. Since hunting has been banned, humpbacks have no predators except an occasional orca whale, which targets young or injured animals.