Nurse sharks live in warm shallow waters in the Atlantic, Pacific, and Indian oceans. Nurse sharks' mating behaviors, like those of other sharks, are largely unknown to scientists. Scientists who have been studying nurse shark mating behavior for years in the Florida Keys are now using Crittercam to assist their research, and they are very excited about the potential of this new technology.

Students will learn some basic information about nurse sharks and read articles describing recent studies in the Florida Keys. They will also read about shark conservation programs and discuss how nurse shark mating studies might assist shark and ocean conservation. They will conclude by writing grant proposals pretending that they are scientists who want to renew their funding for research into nurse shark mating behaviors.

Geography, life sciences

Standard 8: "The characteristics and spatial distribution of ecosystems on Earth's surface"

Two to three hours

• Computer with Internet access
• Writing materials

Students will

• read and answer questions about nurse shark mating behaviors;
• read and answer questions about articles on nurse shark studies and report their findings to the other students in their groups;
• read and discuss a Web page about shark conservation programs; and
• write grant proposals pretending that they are scientists who want to renew their funding for research into nurse shark mating behaviors.

Have students go to Animal Diversity Web. Ask them to read the paragraph on reproduction and answer the following questions in a class discussion:

• Do we know much about nurse shark mating habits?
• What are two ways that nurse shark eggs develop?
• How many pups do nurse sharks tend to have at one time?

Explain to the class that nurse shark mating behavior, like that of other sharks, is largely a mystery to scientists. Scientists, however, are trying to use Crittercam to learn more about how and where nurse sharks mate. Ask students how they think Crittercam might help us learn about nurse shark mating behaviors. (If students have not yet been introduced to Crittercam, they can learn about it at the Crittercam Chronicles.)

Divide the class into groups of three. If your number of students is not divisible by three, it is okay to have a few groups of four.

Assign one member from each group to read one of the following three National Geographic News articles. For groups of four, have two students read the same article. They can also look at the pictures in the "shark photo gallery" link at the top of each article.

As students read their assigned articles, ask them to write answers to the questions about the articles.

Scientists Study Nurse Shark Mating Habits

• Why is this part of the Florida Keys a good place to study nurse shark mating?
• Why are these nurse sharks easier to "track down" than other sharks?
• Can scientists track the same shark in the same place from year to year?
• Do nurse sharks often attack people?
• How big are the nurse sharks that these scientists are studying?
• What do the scientists do when studying nurse sharks?
• Why do they want to get DNA samples? What can these samples reveal about nurse sharks and perhaps other types of sharks?
• What information will Crittercam try to determine about nurse sharks?

Researchers Tag Sharks to Study Breeding Habits

• Why have scientists built the perch?
• What types of tests do scientists perform while waiting for the sharks, and why?
• What patterns do the scientists observe upon the sharks' arrival? Who arrives first and last, and how do they behave?
• Do the sharks appear to be bothered by the scientists?
• How and why do the scientists capture the sharks?
• Do the sharks die when they are out of the water?
• What procedures do the scientists perform once they have a shark out of the water?
• Do these scientists kill sharks for research? Why or why not?

Crittercams Provide Insights into Nurse Shark Behavior

• What have the scientists discovered about nurse sharks? List as many facts as you can find in this article.
• What is inbreeding, and why would it be a potential problem for nurse sharks? [Hint: Think about why it is illegal for people to marry their close relatives, such as siblings or first cousins.]
• What discovery has led scientists to believe that nurse sharks might have a built-in solution to the inbreeding problem?
• Are the males particularly successful when pursuing females to mate with?
• Do the sharks appear to be bothered by the Crittercam?
• What two major questions do scientists hope Crittercam will help answer?

After students have read their assigned articles and answered the questions, have them share what they have learned with the other members of their group. In groups of four, the two students who read the same article should take turns describing what they have learned and how they have answered the questions.

Have all students read about shark conservation at WildAid: Shark Conservation Program.

After they have read the information at the WildAid Web site, hold a class discussion about the answers to these questions:

• Most nurse sharks are not endangered, nor are they popular food sources. Can you think of any ways that studies of nurse shark mating behavior might help general shark or ocean conservation efforts anyway?
• How might the Crittercam studies of nurse shark mating behaviors help scientists in their overall efforts to promote shark and ocean conservation?

Have students imagine that they are scientists who have been studying nurse shark mating behaviors for several years. Their grant is about to run out, but they have a lot more work to do. Ask them to write one- to two-page grant proposals describing their research and explaining why it is important that it continue and that they receive additional funding.

Have students research the gray nurse shark, a highly endangered nurse shark from Australia. They can begin at the Web site of the National Parks Association of New South Wales. Ask students to report on why this shark is endangered and what is being done to try to save the species.

This material is based on work supported by the National Science Foundation under Grant No. 0229817.

Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

Animal Diversity Web
National Geographic News: Crittercams Provide Insights into Nurse Shark Behavior
National Geographic News: Researchers Tag Sharks to Study Breeding Habits
National Geographic News: Scientists Study Nurse Shark Mating Habits
National Geographic: Crittercam Chronicles
WildAid: Shark Conservation Program