Standard 8: "The characteristics and spatial distribution of ecosystems on Earth's surface"
Standard 18: "How to apply geography to interpret the present and plan for the future"
Write the word "extinction" on the board. Ask students to define this word, and ask if they know of any animals that have become extinct.
Discuss as a class the reasons an animal might become extinct. Ask students to contribute ideas, and list their ideas on the board. Contribute your own suggestions if students have a hard time coming up with ideas. For example, you might mention loss of habitat due to human activities, or change in a region's climate or water temperature.
Have students look at these pictures of monk seals. You can also have them watch a video (click on the photo of the monk seals) captured by placing a Crittercam on a monk seal's back. Ask a student to locate Hawaii on a wall map. Make sure that the entire class can see where it's located.
Have students look at this map of the Hawaiian Islands. Ask them to find the main Hawaiian Islands. Explain that people live on these islands and most of them have cities, towns, and vacation resorts.
The northwestern Hawaiian Islands, on the other hand, are not inhabited by humans. Many of them are part of the Hawaiian Islands National Wildlife Refuge and the Northwestern Hawaiian Islands Coral Reef Ecosystem Reserve. Although Hawaiian monk seals live in the waters of both parts of Hawaii, they are mostly found near the northwestern islands.
Inform the class that monk seals are on the brink of extinction. The population of monk seals that lived in the Caribbean has already gone extinct, and the populations in Hawaii and the Mediterranean are in grave danger of becoming extinct. Scientists are studying these seals to see if they can prevent this extinction from happening.
Ask students what they would do first to help the monk seal. The students should realize that they would first need to gather information about the monk seal and find out why it's in danger. If they didn't gather this information, they wouldn't know the best way to help the seal. This information can be gained by conducting experiments, observing the seals, talking to other people who have studied the seals, and reading about the seals.
An analogy to help students understand the above concept would be if a pet became ill, perhaps vomiting or acting very tired all the time. If they took the pet to the veterinarian, the vet would ask questions to find out what was wrong with the animal. The vet might ask such questions as "What has Snoopy been eating lately?" or "Does Muffin go outside?"
The vet would also conduct tests to see what was going on inside the animal's body. He or she might even use the Internet or some books to help figure out what was wrong. In these ways, the vet would gather enough information to give Snoopy or Muffin the best possible treatment.
Divide the class into small groups.
Ask groups to imagine that they are teams in charge of researching why monk seals are endangered. Ask them to discuss and list the initial questions they would ask in their investigation. For example, they might ask, "What do monk seals eat?" to find out if the seals' main food sources are depleted.
Other factors to investigate might include whether human impacts have increased ("What human activities harm the monk seal?" and "Have these activities increased?") and whether there have been changes to the climate or water temperature where monk seals live. Ask each group to come up with at least four questions.
If you teach advanced or older students, also have them write why they've asked each question. In the first example above, they would write, "We want to know whether food sources are decreasing."
If the above instructions are too complex for your students, do this part of the lesson as a class rather than in groups and provide them with hints.
Have students to go the Mysterious Monk page and take turns reading the sentences about monk seals to the rest of the class. When they have finished reading, discuss these questions:
- Have many monk seals been born on the main Hawaiian islands?
- How does a monk seal mother treat her pup in its first few weeks of life? Does she spend a lot of time with it or leave it alone?
- What do monk seals eat?
- What do monk seals do at night and during the day?
Share these additional monk seal facts with the class:
- Most Hawaiian monk seals don't survive more than one year.
- There are only about 1,300 monk seals left in Hawaii.
- Monk seals find most of their food in waters that are more than about 200 feet (60 meters) deep.
- They turn over rocks on the seafloor looking for fish that may be hiding.
- Human debris, such as fishing nets, can injure or kill monk seals. They can get caught in the debris and drown.
Now that the class has this additional information about monk seals, allow groups to add new questions to their lists. For example, they might add the question "Is there more human debris in the ocean now than in the past?" Ask each group to try to add at least two questions to its list.
Discuss the groups' lists as a class. What factors do they think might be most important to study in order to find out why monk seals are in danger of extinction?
Ask groups to imagine that they are going to Hawaii to conduct Crittercam studies on monk seals. They will look for seals on the beach, attach Crittercams to their backs, retrieve the cameras after a few hours or days, and watch the videotapes to see if they hold clues about the seals' behaviors and habitat.
Ask each group to look at its list of questions and check the ones that they think Crittercam will be the most helpful in investigating.
Describe these steps that a Crittercam team would take in a study of monk seals. You might want to write them on the board so everyone can see them.
- Locate monk seals on the beach.
- Work together to sneak up behind a resting seal and put a net over it.
- Give the seal an injection of Valium to sedate it.
- Glue the Crittercam onto the seal's back with a harmless adhesive. Also attach a time-depth recorder (TDR) to measure the time the seal is underwater and the depths it goes to at each point in its dive.
- Leave the seal alone and wait until it ventures into the water.
- Listen every hour for the beep that says the seal has returned to the beach.
- Find the seal once it does, sneak up on it again with a net, and remove the Crittercam.
- Rewind the videotape and watch it.
Have groups plan a skit showing how they will implement this study. Their skits should consist of two parts:
- The first part should demonstrate the above steps to place a Crittercam onto a seal.
- The second part should describe some of the things they hope Crittercam might reveal about the monk seals' lives. They should base this second part on the questions they listed earlier in this lesson.
Have students perform their skits in front of the class.
Describe to the class the results of Crittercam studies on young Hawaiian monk seals:
- Young monk seals are very social. They swim together.
- Young monk seals are in danger of being eaten by sharks and being attacked by adult male monk seals.
- Strong young monk seals go to the same deep areas as adults to find their food, but weaker ones don't go that deep and have a hard time finding food.
- Both young and adult monk seals go to the ocean floor and overturn rocks with their snouts to find and eat fish hiding in the rocks.
- Some young monk seals are not strong enough to overturn the rocks.
Have students draw pictures showing what each of the above scenes might look like as seen through Crittercam.
Discuss how these Crittercam images might help scientists figure out why young monk seals are having problems surviving past their first year of life.
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.
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