To see photographs of the Northern Right Whale (Eubalaena glacialis) click here.
Northern Right Whale (Eubalaena glacialis)
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protected: © 2002 Kelvin Aitken.
All rights reserved. Students may use this information for personal research
only. Not for commercial use.
Northern Right Whales
are part of the Balaenidae family of Right Whales.
Mature females are larger than males growing to 100 tonnes and 17 meters.
Calves are born at 4.5-6 meters in their temperate winter breeding grounds.
Females generally breed once every three years.
Northern Right Whales were once found from the Azores in the eastern
Atlantic north and across to the eastern Atlantic from Canada south to
Florida. Now the main population is found in the Canadian and eastern
USA coast. There may be a small population still in the north east Pacific
but sightngs are
very
rare.
A second species or sub species is found off the coasts of north west Pacific countries from Japan to Russia. This Right Whale has recently been descirbed as the Japanese Right Whale (Eubalaena japonica) based on minor differences and DNA comparisons.
In essence
all Right Whale species are identical in appearance to the casual observer
with species identification being based on geographic location.
Prior to their complete protection in 1937 Southern Rights were hunted
close to extinction due to their being the “right” whale
to hunt; slow moving, shore hugging whales which floated when
dead. Cessation
in hunting has seen their numbers increase over the years in the southern
hemisphere but the northern population struggles to remain vialble.
The Norhtern Right Whale may become extinct very soon. Current
estimations of population size vary from 200-300.
The most distinctive feature of Northern Right Whales is their raised
patches of skin called callosities on the head (which is about 1/3
of
the body length), snout and lips. These rough, pale patches may be
any colour from white to yellow or pale pink and contrast starkly
with the
overall black to dark grey colouration of the body. The surface of
the callosities is very rough and jagged due to the attentions of
whale lice
which feed on and sculpt the thick skin mounds into pads of course
sandpaper. These callosities are easily spotted when the whale comes
to the surface
to breath especially since they also often raise their chin or entire
head during social contacts with other whales.
Some
speculate that Northern Right Whales can be distinguished from the
Southern Right
Whale (Eubalaena australis) by a larger amount of callosity material
on the head and less on the edge of the lower lip. However variety
in callosity material and colouration between individuals, groups
and populations make such observations unreliable and redundant
when their geographic seperation by the equator is considered.
Since these are gregarious animals they often approach boats closely
so that these markings are easily seen below the surface. Each whale
has
a unique pattern of callosities allowing animals to be individually
identified. Unlike other species of whale such as humpbacks or sperm
whales the posterior
edges of the flukes are usually smooth showing no unique markings
and the underside is devoid of any patterns, being plain black
or dark
grey
like the dorsal surface. On the belly, particularly around the genitals,
are varied patches of white, which are also unique to each individual
but harder to observe.
Northern Right Whales have been seen to engage in mating behaviour off
Florida and Georgia.
Mating among these whales is a complex affair. Males compete with
each other to mate with a receptive, or even non-receptive, female.
There
is
much chasing and manoeuvring to get the female in the right position,
all the while fending off the interference of competing males who
push and shove or gouge with their rough callosities. Successful
mating
is
only obtained by a persistent male as the female will often roll
onto her back in order to foil the advances of the competing males.
The
actual
act of mating does not guarantee that a particular male will succeed
in reproducing his genes as other males who mate after will flush
out his
sperm with theirs as the massive testes, the largest of any living
animal, produce enough sperm to flood the females ovaries.
The shore hugging habits of the Norhtern Right Whale (Eubalaena glacialis)
make land based viewing a viable alternative to the more expensive
and
uncomfortable boat viewing. Southern Rights will often swim right
within the surf zone of sandy beaches but will rarely strand. Females
feed
and
nurture their young in the shallows where they can best protect their
young from predators such as their Killer Whale cousins or the Great
White
Shark.