Introduction-Blake and I first wanted to study sharks and their migration habits. After Catalina, we decided to narrow it down to leopard sharks. This way, we actually got to see the thing that we were studying. When we were learning about leopard sharks, we realized that this topic would be good for our class because everyone saw leopard sharks, and everyone seemed to be very interested in them.
In this project, we talk about the location, eating habits, habitat preferences,
and any other general information about leopard sharks we could find.
We also wanted to find out how overfishing of their prey affects the population
of the leopard sharks. Unfortunately, we were unable to find any information
on this subject at this time. I think this project will be very interesting
to our class because they have witnessed these cool animals face to face.
This will give them more of a backround of what they saw.
Research
Data-We saw the sharks on all of our snorkels on the Catalina
trip. They were all near the shore in shallow water. We even saw a huge
pack of over 15 leopard sharks near frog rock about 30 feet off the shore.
Our one experiment was to explore the temperatures at different locations
and different depths in the ocean areas around Catalina Island. Because
we had already researched the habitat preferences of leopard sharks, we
could figure out by looking at the area and figuring out the temperature
if leopard sharks lived around that area or not.
To find out the temperature, we took water samples from the bottom. Then
we took the temperature of the sample. Unfortunately, the data was inconclusive
for that depth. When we got back, we looked at buoy data and concluded
that the buoy said the same thing. For the depth that we measured, the
water was actually warmer at the bottom than it was at the top. We had
different theories, but no specific answer. It may be because it cools
slower.
The leopard shark is one of the most abundant shark species found at Howland’s
Landing, where we went for our trip. We saw most of the leopard sharks
in shallow water by the beach. The leopard sharks can be found as far
down as 300 feet below the surface. During mating season, they tend to
stay in shallow water and they travel in packs. During the winter and
spring they migrate out to deeper water. Fortunately, our trip was during
mating season, so we got to see a huge pack of leopard sharks. We saw
around 20 leopard sharks! While mating, the female tends to have between
four to twenty nine pups. Some conservationists are worried because in
Monterey Bay they are fished for sport. Unfortunately, like most sharks,
their rate of multiplying cannot keep up with the numbers that are being
fished.
Identifying a leopard shark is fairly easy. They can be identified by
their grey skin, black stripes, and black spots under the stripes. Identifying
a male from a female is more difficult. Full grown females tend to be
a foot longer than a full grown male. If you ever see a gigantic leopard
shark, it’s probably a female. The leopard sharks’ diet includes
crustaceans, mollusks, octopus, and small fish such as sardines and anchovies.
Leopard sharks are harmless to humans. They are actually very shy and
try to stay away from humans. When we researched leopard sharks online,
we found that there has been only one recorded attack in history, and
the man wasn’t severely injured.
Conclusion- We hope that our project has taught you more about the leopard shark. We hope that our project will help later years to understand why the sharks live where they do and what they are doing there. The leopard shark is an amazing animal. We hope that sometime in the near future we find out how el Nino and la Nina affect the leopard sharks, their offspring, and their migration habits.
Works Cited
Humann, Paul.
Coastal Fish Identification. Jacksonville, Fl. New World Publications:
1996.
Taylor, Leighton etc. Sharks & Rays. Sydney, Australia. Us
Weldon Owen Inc. 1997.
http://www8.nos.noaa.gov/onms/park/Parks/SpeciesCard.aspx?pID=3&refID=2&CreatureID=62
