Basking Shark Essay, Research Paper
Among the masters of the sea, lies a sluggish monster. Cetorhinus
maximus is just that, although more generally known as the Basking shark. This
interesting animal has some unusual characteristics which include its physical,
behavioral, reproductive, and feeding attributes. Other details about the Basking
shark, consist of its habitat, distribution among the waters, ecological
relationships, and research being done on this gentle shark.
Basking sharks have been known to range from between twenty to fifty
feet long, but are more commonly closer to thirty feet (Allen, 1996, 158). The
smallest recorded Basking shark was sixty-five inches long, which is the
estimated size of one at birth. There have been no significant differences found
to exist in the *age*-length relationships of C. maximus populations World-Wide.
Although all Basking sharks are large, the females tend to be quite a bit bigger
than the males, which is probably because they have to carry a whole other
organism within (Harman, 1996, 21).
Basking sharks have, at some point in time, also been known as the
elephant shark, the Bone shark, sailfish shark, and sunfish. The reason this
shark is occasionally referred to as the Bone shark, is because when they die,
they sink (their density is greater then the water’s density) and are ravaged
among the sea floor, by rocks, etc. (Steel, 1985, 132). However, when they do
finally wash up on shore they are usually quite mutilated; their skeletons are all
that remain. Hence the name, Bone shark. Although the Basking shark most
appropriately resembles the Whale shark, its closest relative happens to be the
* I could not find, in any of my many sources, the life span of the Basking shark*
great white shark (http://www.askjeeves.com/MetaAnswer.asp?MetaEngine
=Lycos&logQID=8F7C6F5E10E0D2119B5300104B2AFFF7&qCategory=SCI_&q
Source=0&frames=yes&site_name=Jeeves&scope=web&r=x&MetaTopic=The+B
asking+Shark+Project&MetaURL=http%3A%2F%2Fwww.isleofman.com%2Finte
rests%2Fshark%2Findex.htm&EngineOrdinal=3&ItemOrdinal=1&ask=basking+s
hark+metasearch&MetaList=http%3A%2F%2Fwww.isleofman.com%2Finterests
%2Fshark%2Findex.htm&ask.x=22&ask.y=1).
When alive and healthy, Basking sharks are grayish brown, and even
black on the top half of their body and a much paler version of those colors on
the bottom. They have a thick covering of spiky denticles along their whole body
(Allen, 1996, 273). Their enormous amount of denticles, make their skin
stronger than cowhide (Allens, 1996, 160).
To give an idea of the size of the Basking shark, picture this scene in your
mind: you and your family are out sailing. A “small” six ton Basking shark jumps
out of the water next to your boat. As it crashes against the water in its
downfall; the rise of the wave that is caused is as tall as a three story building,
possibly even larger (Allen, 1996, 273). Hopefully that gives you at least a small
idea of how massive these sharks are. However, in case that wasn’t convincing
enough, here are some measurements taken off of a mere twenty-nine foot
Basking shark: head: 1 ton; liver: 1850 lbs; fins:1 ton; tail: half a ton; skin: 1 ton;
meat and back: 3000 tons; guts: half a ton; stomach and intestines: half a ton to
1 ton; the total of that whole shark is almost seven tons (Allen, 1996, 271-272)!
If you think those numbers are amazing, listen to these tasty facts: Basking
sharks have a hundred or more teeth, to a row, and row upon row upon row of
tiny, practically useless teeth (Blassingame, 1984, 90). Their mouth is so big
that a child can walk into it without even bending down (Harman, 1996, 22)!
The swimming patterns of Basking sharks greatly reflect their behavior
among one another. They have been known to swim in a line, one behind each
other, and also to swim round and round in circles, giving the impression of a
“sea serpent” (Allens, 1996, 271). Basking sharks either travel alone, in pairs,
or in schools of up to 100 members (http://www.askjeeves.com/FinalAnswer.asp
?qCategory=SCI%5F&Link=http%3A%2F%2Fwww%2EEnchantedLearning%2E
com%2Fsubjects%2Fsharks%2Fspecies%2FBaskingshark%2Eshtml&Title=Zoo
m+Sharks&Answers=1&ajparam_list1=2&ajparam_fillers=%7C2%5B3631%5D%
7C&ajparam_qid=1401&site_name=Jeeves&scope=web&ask=Where+can+I+fin
d+information+on+the+animal+basking+shark%3F). They even got their name
through one of their behavioral traits: basking in the sun. These sharks have a
habit of laying on the surface of the water with their backs exposed. With their
first dorsal fin guiding them along the water, just sunbathing (Allen, 1996, 272).
Although the Basking shark is generally known for it’s gentle nature, when
harpooned, or endangered, this sluggish animal, can turn into a sailors worst
nightmare (Allens, 1996, 273)!
Basking sharks are believed to be ready to mate between the ages of two
to four years (Harman, 1996, 26). They usually have one or two live young and
are thought to have the largest babies (in length) at birth (Harman, 1996, 26).
Mating usually occurs in May and the gestation period lasts approximately two
years, if not more (Steel, 1985, 133). For quite a few years, scientists thought
that Basking shark females did not have embryos. And the most widely
accepted theory had been that Basking sharks are viviparous, conceiving their
young at the surface, and have birth in the deep ocean (Allens, 1996, 273).
Recent research has proven differently. Female Basking sharks do in fact have
embryo’s, along with huge amounts of eggs that are consumed by the embryo’s
during the gestation period (Steel, 1985, 133). A very odd trait of the Basking
shark, is that young sharks are rarely found and have been thought to remain in
deep water until full-grown (Steel, 1985, 134). They do however, swim away
from their mothers right after they’re born. So, the mother does not care for the
young sharks after birth (http://www.askjeeves.com/FinalAnswer.asp?qCategory
=SCI%5F&Link=http%3A%2F%2Fwww%2EEnchantedLearnin
jects%2Fsharks%2Fspecies%2FBaskingshark%2Eshtml&Title=Zoom+Sharks&A
nswers=1&ajparam_list1=2&ajparam_fillers=%7C2%5B3631%5D%7C&ajparam
_qid=1401&site_name=Jeeves&scope=web&ask=Where+can+I+find+informatio
n+on+the+animal+basking+shark%3F).
The mouth of the Basking shark is not only very large, but also quite
effective during feeding times. These sharks feed by keeping their mouths wide
open while swimming and just have a continuous flow of water going in, which
the gill rakers strain for plankton. Gill rakers are bristle-like fibers with a sticky
coating which serve as a filter to find food (along with taking oxygen from the
water). Scientists estimate that an average size shark, swimming at two knots,
can filter a thousand tons of sea water over it’s gills every single hour
(Blassingame,1984, 91). Basking sharks are strictly plankton-eaters. However,
one theory states that the sharks semihibernate in deep water and lose their
gill rakers, in which case they go deeper to feed on plants and small shellfish
(Blassingame, 1984, 92). Losing their gill rakers in winter is a pretty universally
known theory, since evidence of sharks without gill rakers, but growing new
ones during winter, have been found (Blassingame, 1984, 92). What they eat
over winter, or whether or not they just hibernate, is not yet an established fact.
Basking sharks are usually found in temperate waters with lots of
plankton. Temperate waters are the waters that are not considered tropical or
arctic (Antarctic). They are temperatures like from San Diego to Alaska. Oddly
enough, they usually enjoy the water much colder than your average sea
creature. They are usually found off North America, ranging from
Newfoundland to North Carolina. In the Pacific, they are commonly found from
the Gulf of Alaska all the way down to Baja, California. During the winter they
have been thought to disappear completely from around North America but are
still found occasionally in the Pacific.
The Basking shark’s, major enemy are humans. Men hunt them for their
meat and fins, but primarily for their lavish supply of oil. In one shark, you can
usually find sixty to seventy gallons of oil, which humans use for industrial
reasons. C. maximus, which is believed to be the only kind of Basking shark,
has an adaptation which helps when trying to protect themselves from man
(Allen, 1996, 273). That adaptation is their body slime, which quickly rots fishing
nets, so they can escape (Steel, 1985, 132). The only other enemy of the
Basking shark are parasites. The blood sucking lamprey (Petromyzon marinus)
stick onto these sharks throughout the seas and the only way the sharks can rid
themselves of the lampreys are to jump to awesome heights from the sea (Allen,
1996, 272). The number of Basking sharks is at this time unknown, but could
very easily be decreasing since the it is hunted by humans for its meat, fins, and
oil (http://www.askjeeves.com/FinalAnswer.asp?qCategory=SCI%5F&Link=
http%3A%2F%2Fwww%2EEnchantedLearning%2Ecom%2Fsubjects%2Fsharks
%2Fspecies%2FBaskingshark%2Eshtml&Title=Zoom+Sharks&Answers=1&ajpa
ram_list1=2&ajparam_fillers=%7C2%5B3631%5D%7C&ajparam_qid=1401&site
_name=Jeeves&scope=web&ask=Where+can+I+find+information+on+the+anim
al+basking+shark%3F).
Quite a few organisms would be effected by the removal of the Basking
shark from the ocean, however in different measures. Without the sharks,
plankton would thrive to an unruly amount, which therefore would cause less
sunlight to reach the deeper areas of the ocean, killing off, or hurting the
organisms which use that sunlight to survive.
Many sharks are being researched by modern day scientists to help fight
life-threatening diseases. Basking sharks in particular, are used for research in
trying to destroy cancer and heart disease. This is because their enormous
supply of oil contains chemicals which is leading medical researchers to cures
for these often fatal illnesses (Allen, 1996, 160). Basking shark cartilage
contains an abundance of a substance that stops the growth of new blood
vessels toward solid tumors, which overall, restricts the growth of tumors
(http://www.askjeeves.com/FinalAnswer.asp?qCategory=SCI%5F&Link=http%3
A%2F%2Fwww%2EEnchantedLearning%2Ecom%2Fsubjects%2Fsharks%2Fsp
ecies%2FBaskingshark%2Eshtml&Title=Zoom+Sharks&Answers=1&ajparam_lis
t1=2&ajparam_fillers=%7C2%5B3631%5D%7C&ajparam_qid=1401&site_name=
Jeeves&scope=web&ask=Where+can+I+find+information+on+the+animal+baski
ng+shark%3F). Other chemicals within the Basking shark have been found to
lessen, or slow down blood clotting (http://www.askjeeves.com/FinalAnswer.asp
?qCategory=SCI%5F&Link=http%3A%2F%2Fwww%2EEnchantedLearning%2E
com%2Fsubjects%2Fsharks%2Fspecies%2FBaskingshark%2Eshtml&Title=Zoo
m+Sharks&Answers=1&ajparam_list1=2&ajparam_fillers=%7C2%5B3631%5D%
7C&ajparam_qid=1401&site_name=Jeeves&scope=web&ask=Where+can+I+fin
d+information+on+the+animal+basking+shark%3F).
Basking sharks are among the most interesting and mysterious giants of
the sea. It is hard to believe that the only creature killing these sharks off are
humans, and yet many groups, including English Nature (formerly the Nature
Conservancy Council) recommend the species be listed as an endangered
species. However, that idea has been repeatedly rejected by the UK
Government (http://www.askjeeves.com/FinalAnswer.asp?qCategory=SCI%5F&
Link=http%3A%2F%2Fwww%2EEnchantedLearning%2Ecom%2Fsubjects%2Fs
harks%2Fspecies%2FBaskingshark%2Eshtml&Title=Zoom+Sharks&Answers=1
&ajparam_list1=2&ajparam_fillers=%7C2%5B3631%5D%7C&ajparam_qid=1401
&site_name=Jeeves&scope=web&ask=Where+can+I+find+information+on+the+
animal+basking+shark%3F). It just goes to show, that ecological relationships
should not be messed with by foreign means. I hope that one day all creatures
can live in complete balance with one another, and each gain success and
failure equally.