The Great White Shark
Paleontologists are not just people who work on old fossils. Many
workers are very interested in living groups. Some living groups have
ancient histories. For example, sharks have existed as a group for
over 400 million years! Unlike the true fishes, sharks do not have
internal bone, but instead have a cartilaginous skeleton. Although many
people are told that sharks are primitive in comparison to other groups,
this is not true. Sharks are effecient and specialized hunters that
have succeeded for millions of years. They are in no way "primitive".
This small exhibit shows an amazing predator; the great white shark.
The 14 or so images
that are located below are the end
result of a pilot project run at the University of California
Museum
of Paleontology, the Department of Integrative Biology, and the Point Reyes Bird Observatory.
Doug has been doing research on the interactions, particularly, feeding
of Great White Sharks on marine mammals along the coast of Central
California for several years now. His research has included autopsying
dead marine mammals, studying the feeding behavior of sharks, and trying to
estimate shark population size. These images are directly related to
the latter two aspects of his research. From a post on the Farallon Islands,
Doug and his crew watch the waters for injured marine mammals and signs of
sharks feeding. When they spot a feeding shark, they travel in a small
boat to the site, and when the shark comes close they stick a small hand-held waterproof video recorder
under the water and film the shark as it passes by
. The sharks are identified
by characteristic marks like scars
and skin blemishes. Most of the pictures in this small exhibit
were taken with the express intent of looking for these scars,
so they may not be the most aesthetic images possible.
However they are the most useful.
The ability to visually identify sharks allows researchers to tell more about
migration, ranges, and the number of individual sharks in the area.
Doug believes that there are a suprisingly small number of individual
sharks off the California coast and that they have larger
ranges than previously thought.
Douglas Long
, a graduate
student in the Department of Integrative Biology, has graciously made
these images available. Below are some still shots from videotape.
PLEASE DO NOT REPRODUCE WITHOUT PERMISSION FROM THE PHOTOGRAPHER.
djl
