Get to know the shark, and you'll find that, contrary to popular belief, it is not a vicious feeding machine with a hankering for humans. Like many other predators in the Animal Kingdom, it hunts when it's hungry, and it attacks when it feels threatened. There are almost 400 species of sharks, and there is much to appreciate about these graceful and powerful creatures. The shark's body design and its amazing senses are marvelous gifts from Mother Nature. Get beyond the Hollywood myths about the shark, and learn about this awesome animal which plays a vital role in the ocean ecosystem.
Sharks fascinate us, perhaps because they're on top of the food chain, and they're called the "perfect predator". They're indestructible. Or are they? There is much concern now over their dwindling numbers. On average, sharks don't reach sexual maturity until they're seven years old, and a female will bear less than a hundred pups in her lifetime. These characteristics make it difficult for shark populations to keep up with commercial fishing pressure.
In April of 1993, the National Marine Fisheries Service implemented regulations that established a federal management program for 39 shark species in the Atlantic, Gulf of Mexico and Caribbean. Let's graph the annual landings of some of these shark species by using the Commercial Fisheries data compiled by the National Marine Fisheries Service Statistics and Economics Division. Input the following in the form:
Click here for step by step instructions on graphing in Microsoft Excel.
Federal management of shark fishing began in 1993. Look at the landings for each species. Do you see trends that are probably due to changing regulations? Describe and explain. Give an example where regulations may have gotten tighter. Any examples where regulations may have been loosened? What do you think prompted these changes in regulations?
Repeat the exercise by extending the Year Range to the most recent available (Latest Year). How do the trends change over the extended period of time? Why?
Laura Rose, Virginia Sea Grant, Virginia Institute of Marine Science
45 min - 1 hr.
Graphing paper ruler OR Excel
Natl. Science Standards
Ik-1 IK-2 L5-3 L5-4 L9-4 L9-6 PS5-2 PS9-3
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