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Expedition Review
Location: Crystal River, Florida
Day 18
by Wayne Brown |
Now that The Crystal River Florida Manatee Online Expedition is over it is time to think about what we learned. We knew a lot about manatees before the expedition, but we learned even more about manatees from the manatee scientists and researchers we met.
Here are some of the things we learned during our expedition:
Manatee Intelligence: We used to think that manatees were kind of dumb, like cows. The manatee brain is not that big compared to the size of its body. A manatee brain also does not have all the wrinkles in it as the brains of intelligent mammals, like dolphins and humans. Mr. Bob Bonde and Dr. Lowe think that manatees are pretty intelligent. They think manatees are about as intelligent as pigs. Bob says that new research seems to show that the size and wrinkles of a brain may not be a good sign of intelligence. Bob says that the number of brain cells, called neurons, and how tightly packed together they are may be a better sign of intelligence. Bob and Dr. Lowe think manatees are fast learners. Dr. O'Dell says that we need more research before we can be sure how intelligent manatees really are.
Manatee Navigation: Bob told us that manatees can find their way around underwater even if the water is so dirty you can't see your hand in front of your face! Bob's group has no idea how manatees can find their way around. Manatees don't have sonar like dolphins do. Manatees may be able to use sound for navigation, but we do not know that for sure. Maybe manatees have an extra sense that scientists don't know about.
Manatee Babies: We used to think that that manatees only had one calf at a time. We learned that once in a while a mother may have twins.
We learned, from our visit to the Sirenia Project labs on Day 12 and seeing the satellite tracking data, that manatee mothers go away to a place by themselves to have their babies. After having their baby a mother will stay at that place for several weeks to bond with her baby.
We used to think that the mother manatees push their babies to the surface to breathe, as soon as they are born. Dr. O'Dell told us that the calves can swim to the surface and breathe on their own as soon as they are born, but the mother is right there watching her baby in case anything goes wrong.
We knew that manatee babies are sometimes orphaned if they become separated from their mothers and can't find them. We did not know that mothers may leave their babies on purpose. Dr. O'Dell told us that a mother manatee will sometimes leave her baby if the calf is not a healthy baby. This may seem cruel, but for manatee survival it is important to have healthy babies that will survive and reproduce. The mother spends two years with her baby teaching her calf the survival skills it will need to survive on its on. The mother is somehow able to know if there is something wrong with her baby. Even if she tries to care for it and teach it the baby will not grow up and be able to have babies. The mother will leave her unhealthy calf so she can have another baby, without waiting for two years, that may be healthy and will be able to survive.
Also sometimes calves can be orphaned if a group of male manatees successfully separate a cow and her calf. The males try to do this so that they can mate with the female.
We used to think that when babies were about two years old they left on their own, leaving their mothers. From the satellite tracking data at the Sirenia Project labs we learned that when their calves are about two years old the mothers take their calves on a long trip. While her calf is distracted the mother will swim away leaving the calf on its own. Fortunately the calf has learned how to survive from the two years it was with its mother.
Manatee Survival: We learned from Bob that there are between 2,500 and 3,000 manatees in Florida. He told us that the manatee population is stable and seems to be growing. Bob thinks that manatee will survive into the future because they are very adaptable. But they can't do it without our help. People need to obey the laws protecting manatees.
We used to think that propeller guards were good for preventing manatees from being killed by boats. We learned from manatee treatment centers that the propellers can cut a manatee's skin. Usually the manatee survives the injury. The real problem for the manatee is not the cut but being hit so hard by the fast moving boat. Dr. O'Dell told us "speed kills"!
Ecosystem: Manatees are part of the Florida coastal ecosystem. If manatees are healthy it shows us that the ecosystem is probably healthy. If manatees are sick, it probably means that the ecosystem is sick. Bob and Dr. Lowe are closely watching the virus Dr. Lowe has discovered on Gulf coast manatees. (East coast manatees don't have this virus.). This virus could somehow be a sign of the health of the ecosystem here.
What Do You Think?
We found some things that people disagree about during our expedition.
Think about these things and talk about them in class.
(TEACHERS: Go to the Teacher's Link
to find suggestions on leading class discussions on these topics.)
Land Development: Problem - About 1,000 people are moving into Florida every day. (That is probably more people than in your whole school!) People need a place to live. People also like recreational activities like, boating, fishing, water skiing, etc. How do we balance the needs of people and the survival of manatees?
Manatee researchers think coastal development is destroying manatee habitat. They say less habitat means fewer manatees. More people also means more boats which can injure and kill manatees. More people means more pollution.
Land developers say people are moving to Florida and need a place to live. Many people want a home near the water. The developers say they are not doing anything against the law. They are just giving people what they want. They say there are plenty of protected areas and manatee sanctuaries. Developers say that manatees are growing in number so it shows that manatees are adapting well to coexistence with people. Developers say that as people move in pollution can be controlled and prevented.
Boats: Problem - Each year many manatees are injured and killed by boats. More and more boats are going into the waters in the same places manatees live. How do we balance the wants of people and the survival of manatees?
Manatee researchers say boats should have propeller guards to protect manatees from injuries from propeller cuts. Researchers also say more areas should be set up as idle speed zones to protect manatees. Researchers say boats are quicker and faster than manatees and manatees sometimes can't get out of the way quick enough.
Boaters say that propeller guards get clogged up with grasses, algae and seaweed, and are not that effective in protecting manatees. Boaters say there are already plenty of areas that are set up as idle speed zones to protect manatees. Boaters say manatees live underwater and can easily hear the boats. If the boats come too close the manatees can easily swim out of the way.
Touching Manatees: Should people be allowed to touch, pet or scratch manatees?
Most people, dive shop owners and manatee researchers think it is OK to touch manatees. Ms. Kleen thinks manatee touching is not harmful to manatees as long a people do it properly. She says that you should not bother a manatee if it is sleeping, you should not come between a mother and her calf, you shouldn't poke or kick a manatee, you shouldn't try to ride on a manatee, and you shouldn't chase a manatee. You also should not feed a manatee. Ms. Joyce Kleen told us that if the manatee wants to interact with you it will come to you. When the manatee is done playing it will swim away, but don't chase after it. Bob and Dr. Lowe think that interaction between manatees and people is good because it is educational. The more people interact with manatees the more people there will be to want to protect manatees. These people will tell other people why they should be concerned about protecting manatees.
Some people think that no one should touch a manatee. They say that any interaction with manatees will make them less wild. If you touch a manatee it will not be scared of people and that may endanger manatees survival. Tame manatees also may swim to boats instead of avoiding them.
What Can I Do?
What can I do to protect manatees? In Florida people can buy special manatee license plates for their cars. Part of the money goes to manatee research, protection and rescue.
You, your class or your school can help manatees by adopting your own manatee! You receive a photo of your manatee, information about your manatee and an adoptioin certificate. The money from your adoption is used for manatee research, care, protection and rescue.
Tell your friends, parents and relatives about manatees. The more people that know about manatees the more people will want to help protect manatees so kids in the future will be able to see manatees, too!
Thanks for joining us on our expedition. We look forward to meeting you at many of the schools we will be visiting for our assembly programs.
Best Fishes for the school year,
Mr. & Mrs. Brown
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