Why
Do Gray Whales Jump?
Excerpt from my book "Gray Whales My Twenty Years of Discovery"
Photos are low resolution of some photos that are included in the book
Remember that you can go whale watching with the author in Baja Mexico. For more information click here.
Why Do Gray Whales Jump?
The topic of this chapter is whale breaching. Why do whales
jump? This behavior is a favorite for whale watchers and
photographers around the world. To be close to a 30 or 40
ton whale as it bursts from the water is awe inspiring and
a spectacle that you never forget. But this behavior is not
well understood.
Many writers and researchers have postulated that breaching
is a behavior used by whales to remove parasites (whale barnacles & whale
lice) from their skin. My observations, started in 1994, convinced
me that parasite removal is not the reason that gray whales
jump. Possibly some parasites do actually get dislodged
during a breach, but I do not think that has anything to do
with why whales jump out of the water.
This book is available after November 15, 2012 with all online
booksellers in either full color print edition, 120 pages, about
100 photos, drawings and original maps. It is also available in
an E-version.for Kindle, Nook or other E-readers.
No other book about gray whales contains the maps and drawings
of the Baja nurseries. Chapters and photos of things never before
covered in a popular science style book about the gray whales.
Most
whales have some barnacles and whale lice. Gray Whales have
many barnacles and whale lice living upon them. In fact gray
whales provide a home for more barnacles than any other species.
Barnacles and whale lice are the topic of another chapter.
I mention this here because if gray whales have the most
barnacles, then gray whales should be the species most likely
of any whale species to be irritated by those barnacles.
Thus they should be the species most likely to be seen breaching
to remove the parasites.
But why would any animal burn up the calories required to leap out of the water,
just to dislodge a few whale lice. Wouldn’t it be far easier and
less
tiring
to simply rub along the bottom of the lagoon? After all the average depth where
the whales hang out is only 30 to 40 feet in the lagoons.
During
a five year span from 2002 through 2006 I observed Gray Whale breaching activity
with particular interest. I wanted to know more about whale breaching. Between
1992 and 1999 I made many trips to Laguna Ojo de Liebre each year, but there
were periods of a week or two at a time when I was not able to be out on the
water while there were whales present. Thus there were gaps of time where I was
not observing the Gray whales on a daily basis.
Finally, beginning with the 2001 gray whale migration season I was able to be
on the water with the whales nearly every day. From 2001 to 2006 my time on the
water began in December and continued into April. In 2004 I was at Laguna Ojo
de Liebre continuously from January 12th to March 21st. I missed only four days
on the water during this ten week time period.
Here
are some of my observations of breaching and my thoughts on
why gray whales breach.
Early in the season there are few breaches observed. Those animals
that do breach are nearly always young immature juveniles in the
one to four year age group. They have returned to the lagoon, but
have no specific whale task to fulfill. They cannot successfully
mate. Most of them are too young to even have the desire to mate.
They are rambunctious and full of youthful energy. They have seemingly
boundless energy much as human teenagers seem infused with an unlimited
high octane fuel supply. We frequently see these juvenile whales
burst from the water in exuberant displays of repeated multiple
jumps. Averaging 3 or 4 jumps per series these energetic whales
are capable of up to 6 or even 8 leaps in a row.
Jumping from the water for a 30 or 40 foot whale that weighs 40,000
to 80,000 pounds demands a significant expenditure of energy. Because
the water inside the lagoon averages 20 to 40 feet in most areas
of whale activity, the whales cannot dive deep and then gain speed
as they swim vertically to the surface. Instead the breaching gray
whale must swim very fast horizontally and then suddenly pull up
in a steep climb out of the water.
Usually by the 3rd or 4th jump the whale is not able to get fully
out of the water and his jumps become more a porpoise like activity,
rather than the impressive straight up breach. Nonetheless a series
of 4 or 5 jumps is impressive and is guaranteed to get an entire
boat of whale watchers very excited.
Two thoughts about the subject of jumping:
1. If whales breech to remove parasites then they should attempt
to land in such a way as to make their barnacle patches hit the water
first. My observations do not prove this to be the case.
2. Second thought; when researchers place tracking transmitters
or tags on gray whales, the whales normally try to remove them. If
breaching is a parasite removal behavior, then to remove an irritating
transmitter the whale should logically begin leaping from the water,
slamming the transmitter down as hard as possible in his effort to
dislodge the irritation. Instead gray whales sound, diving down to
the bottom where they proceed to rub the irritating transmitters
off their streamlined bodies. Earlier in the migration chapter I
mentioned how 7 Gray whales were recently tagged, but only two of
the transmitters worked long enough to provide any usable data. This
is typical for tagged Gray whales.
3. A case of defensive breaching took place in the
early 1980s inside San Ignacio Lagoon. This is one of the few instances
where a Gray whale attacked a boat. A boat carrying some whale
researchers was following a gray whale through the lagoon. Possibly
they were following too close for too long (tailgating and resultant
road rage?). The gray whale finally had enough of them and turned
around and in one mighty leap he breached on top of their 24 foot
fiberglass panga. Amazingly none of the researchers were injured,
but I am sure they learned a lesson in good whale watching manners.
I have been observing baby whale behavior for a long time. Several
years ago I began noting how and what date the babies accomplish
various stages of breaching effort. Sometime around mid-February
the babies have grown large enough and strong enough to be able to
leap nearly out of the water. This maturation is noted by the mother
whales who watch their youngsters with a sharp eye.
During January and early February breaching by mother whales inside
the lagoon is extremely rare to non-existent. Then in the middle
of February something interesting takes place. For a brief period
of one, two or three days - never more than that, mother whales are
seen breaching.
I first noticed this unusual mother breaching activity in 2002. I
was curious and a bit surprised. But I’ve grown to know that
there is no such thing as an absolute when it comes to animal behavior.
I didn’t make note of the specific date that this took place,
but I know it was mid-February.
In 2003 I watched closely to see if the breaching mother whale
activity would take place once more. Surprisingly it did. Again
for 2 or 3 days the mothers were suddenly jumping out of the water.
This uncharacteristic breaching activity took place beginning on
February 20th that year. This appears to be a pattern of reoccurring
behavior where the mother whale teaches the baby how to jump.
I noted the breaching instructional days in each of the years 2002,
2003 & 2004. I also observed that the babies were far more
active in terms of breaching after the lesson days ended. In the
days following the two instructional days the baby whales seemed
to be popping out of the water wherever we looked.
In 2004, I was ready for the breaching lesson days. Those who were
with me February 12th to 15th that year know that one morning I
thought I saw a mother breach and commented that maybe breaching
school was about to start.
Sure enough by the end of the day on
February 13th there were dozens of mothers jumping. Then on the
15th the mother breaching activity abruptly stopped. All the mothers
who wanted to teach their babies how to jump, had done so.
From that day until the last day I was on the water March 21st, I
didn’t see another mother whale breach! I saw plenty of juveniles
jumping and loads of babies, but no mom whales jumping.
For whale watching information
about Gray whales go to our Whale watching in Baja page.
Or buy the book
Gray Whales My Twenty Years Of
Discovery
by Keith E. Jones
Why would mother whales feel the need
to teach their offspring how to jump out of the water? There is
no whale Olympics for them to compete in. The need is more basic
than that.
Breaching is in fact a defensive and offensive behavior. For most
marine animals, if they are being pursued and just cannot escape,
then they will jump from the water as a last desperate effort to
get away. Breaking out of the water can confuse pursuers. Maybe
a Gray Whale baby, being chased by an Orca increases his chances
of getting away if he occasionally leaps from the water.
There are documented cases of whales being pursued by boats and
then turning the tables on the pursuers. By breaching and coming
down upon the pursuing boat the whale was able to aggressively
end the pursuit.
Imagine the impact a jumping 30 ton gray whale has upon an Orca
who is chasing it. That collision is enough to end the chase. A
baby gray whale tail is not strong enough to hurt an attacking
orca. But if a 2,000 pound baby jumps and lands upon an attacking
orca, it just might slow the orca down a bit. Thus giving the mother
and baby a better chance of surviving the encounter.
My conclusion is that breaching of Gray whales takes place for
two reasons. The first reason is pure exhilaration. Jumping makes
the young whales feel good. Jumping makes the macho male whales
feel mighty and macho. The second reason Gray whales jump is to
escape an attack or to attack an attacker.