Journey North Information About
What is the length of a humpback whale?
Calves can be about 15 feet in length. Adults are about 45-50 feet.
How do researchers recognize one humpback from another?
Humpbacks are distinguished by the markings on the underside of their tails (also known as flukes). The patterns
can range from all black to all white, with most having a mix. The researchers pick out distinguishing marks (which
may also be scars -scars on the white portion appear dark and scars on the darkportions of the tails appear white).
A whale named "Cat's Paw" has a mark on her tail that looks just like a paw print. Since humpbacks lift
their tails out of the water when they dive, researchers can see and photograph the flukes, allowing for identification.
Is fluke pigmentation inherited from the parents?
Fluke pigmentation may be influenced by inheritance from the parents. Researchers report that pigmentation varies
among individuals from all black to all white, with every grade in between. Superimposed on the basic pattern are
scars from injuries acquired during fights with other individuals, attacks by killer whales or sharks, or attachment
of parasites such as barnacles, parasitic copepods, lampreys, or others. Injuries to white skin cause black scars
and vice versa.
How do the whale researchers keep track of the individual whales?
Humpback whales originally were identified by a catalog number. But as those numbers started to grow, the researchers
decided they needed a better way to distinguish between the animals (especially when they were in the field). The
habit of giving the whales common names began, but now a problem arose. There were several groups studying whales,
and often the groups gave the same whale different names. It was decided that the groups would come together every
year at a whale naming party and assign specific nam es to each of the newly found whales.
What kinds of requirements are there for naming the humpbacks?
Whale names should be descriptive about one of some of the whale's markings (usually on the underside of its flukes).
Humpbacks have distinctive markings on their tails, patterns of black and white, that usually don't change after
the first year or two. For example, one whale has a pattern that looks like a cat's paw print, hence its name Cat's
Paw. One whale has a marking that looks like the number 7, hence its name
Does the hump serve any purpose to the humpback whale?
The hump (or lump just in front of the dorsal fin) led to its name, but it isn't known if this feature serves any
Why do baleen whales have 2 nostrils and toothed whales have one? Is there a scientific reason
for the difference?
Scientists believe there may be an evolutionary reason for this difference, perhaps in symmetry in the skull and
the development of echolocation. Toothed whales echolocate, using their air passages to generate sounds (air is
moved between sacs under the blowhole to generate high-pitched sounds) . We do not think that baleen whales use
echolocation or, if so, to a much more limited extent. However, baleen whales do generate very low-frequency sounds
that may allow for extremely long-distance communication.
Humpbacks are known as the acrobats of the ocean, often seen breaching (jumping out of the water),
and flipper and tail slapping. For what purpose are these actions?
These activities performed by surface active groups are usually involved in breeding behaviors. Researchers think
the males are competing for the chance to mate with available females. Some of the behaviors shown were breaching,
flipper/pec (pectoral fin) slapping and tail slapping. Breaches and slaps, in addition to being aggressive displays
during courtship, may also be a play behavior in juvenile and adult whales Breaches and slaps may also be used
to remove pesky barnacles or old skin (a form of grooming).
How long can a humpback whale stay under water before coming up for air?
According to scientists at the Center for Coastal Studies, a humpback can probably stay underwater for as long
as 35 minutes. However, on average up in the Gulf of Maine, the length of time is only about 3-5 minutes (feeding
in a fairly shallow area). In the West Indies, the average is 10-15 minutes.
How do whales breath?
Humpback whales are voluntary breathers meaning they have to consciously breath in and out (it's not an involuntary
reaction like we have). They swim to the surface to draw in air through their blowholes. Whales have limited breathing
functions through their mouths. When a whale inhales, it fills up its lungs to capacity each tie and then exhales
90% of its air supply with each breath. Humans exhale only 25% of their lung capacity. The whales exhale through
the blowholes, a whole exhale in less than half a second and sometimes at over 300 mp, while inhaling takes place
in a leisurely second.
What adaptations have whales made for voluntary breathing?
Voluntary breathing is an important adaptation for whales. They must constantly be aware of their location in the
water. Since they are mammals and can drown if they flood their lungs with seawater, they must know when it's safe
to take a breath. It is believed that the area around their blowholes is very sensitive and allows them to know
when they have broken through the surface to the air.
How do whales sleep if they must remember to breath?
Scientists believe whales sleep half a brain at a time (based on studies with dolphins). Whales are known to log
at the surface -- a resting behavior. Boats can often approach quite close at this time during whalewatching, and
it is a time when animals can be in great danger from fast-moving boats unaware of their presence. The animal has
probably shut down half its brain, keeping a part active enough to sense when it is moving away from the surface,
when to make adjustments with its flippers and flukes, and when to take a breath. After a while the whale will
become fully awake.
Why do you think the male Humpback Whales sing? What are they trying to communicate?
The males (and only the males) in the warm breeding waters are famous for their songs - long series of vocalizations
that can last for up to 30 minutes. Maybe they are intended to let other animals know where they are and who they
are. The songs don't seem to be way of attracting partners, as most females seem to avoid the singers. The whales
that sing on the breeding grounds seem to have the same song, although there may be some small variations. As the
season progresses, the songs change too. There is still very much about these whales that we know so little about
(and opportunities for all of you future field biologists).
Have scientists been able to interpret the sounds whales send to each other?
Scientists are studying whale sounds and attempting to understand their "languages." Sperm whales communicate
with click patterns and blue whales produce very loud sounds. Humpbacks (males) are famous for their songs, which
are probably involved in mating rituals and to declare territories. Scientists have been able to record songs that
are repeated units of sound -- some can last as long as 20 minutes. At first scientists though this song was like
a bird's song, but it was discovered that the songs change year to year.
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