Sirenia Farewell and Season Summary for Spring 2002 Farewell from the Sirenia Scientists It's hard to believe it but we've reached the end of the season again. Thanks from all of us to all of you for the opportunity to share our manatee research with you. We learned even more this year. It's been great! Focus on Finding Freshwater Ten Thousand Islands Study Area This was our second season investigating the movements and habits of manatees in the Ten Thousand Islands region of southwest Florida. If you tracked the manatees with us last season, you may recall that we were just beginning to learn about how manatees in this region use the habitat, and what triggered their movements. We now know how very important access to fresh water is to manatees in this region. We have observed them make deliberate moves >from the seagrass-rich feeding areas in the maze of marshy islands to the rivers that feed this region, solely to obtain fresh water to drink. We have learned there are several sources the manatees use to obtain fresh water (some more popular sites than others), but they continue to show us new fresh water sources. How Will Everglades Restoration Affect the Manatees? One important focus of our study was to look at the effects of the Everglades hydrological restoration on manatee distribution in this region. Many canals and dams are being removed so that rainwater and water from Lake Okeechobee and rivers to the north will flow like a sheet over the land as it did historically. As you have learned, manatees seek out freshwater for drinking, and are known to visit the spillways of dams for this purpose. Restoration of the Everglades may result in a more even distribution of freshwater in the region, rather than water concentrated at specific locations for manatees to utilize easily. With continued radiotracking, we still hope to discover whether, and where, manatees will find freshwater when the restoration efforts are completed. Everything They Need So Close to Home One of the most interesting, and surprising, findings from this tracking study was that most manatees remained so close to the area where they were captured. The manatees in the Ten Thousand Islands and Everglades National Park area may not need to leave the region to fulfill their requirements (food, freshwater, thermal refuge in winter). This strong, year-round site fidelity for our study animals indicates that the region can support the needs of the manatees of the area. We are beginning to feel more confident that the movements of these manatees are representative of the manatee population in this region. What Manatees Teach US! We continue to ask questions and formulate hypotheses to explain manatee movements and behavior. I hope that you too have wondered about why a manatee may be moving to a new area, or staying put-- that insight of your own is the beginning of the scientific process! From your own questions, you can create hypotheses and then test and learn whether you were right, or if you now have even more questions!. If you have been with us in past years, you may recall that I have spoken about what we continue to learn from and about manatees, the environment they inhabit, and the dangers this species encounters daily. Iím sure that you can guess what most of these hazards are (hint: boats, many types of pollution, depleted food sources). You probably know that many manatees are accidentally killed by boats each year. We need also to be reminded that many more manatees that are hit by boats each year, survive, but often with horrific injuries. Even though these manatees do not die, what affect do you think these injuries may have on the overall health of the manatee population? For example, do you think that injured manatees may not be reproducing successfully? This is one hypothesis that we currently are investigating. All of us at the Sirenia Project are encouraged that so many students are truly interested in learning more about manatees and science. I am always impressed by what good thinkers ALL the students are that join Journey North! We are always learning and we hope that you have learned along with us. Thank you so much for joining Jim Reid, Susan Butler, Dean Easton, Bob Bonde, and me this year, and learning along with us! Copyright 2002 Journey North. All Rights Reserved. Please send all questions, comments, and suggestions to our feedback form