Sirenia Project Season Summary for Spring 2003 By Cathy A. Beck Restoration of the Florida Everglades: It's Impact on Manatees You may recall that there is a primary reason we are continuing our tracking study of manatees in the Ten Thousand Islands area of southwest Florida: to investigate and document effects of the Florida Everglades restoration on manatee distribution. You may have heard of the tremendous effort to restore the natural flow of freshwater from Lake Okeechobee and rivers to the north, south to Florida Bay and the coastal habitats. Canals that previously channeled water to specific sites, and dams that retained water to prevent flooding, are being removed. The result will be a more widespread dispersion of freshwater. The Manatee's Need to Find Freshwater After three seasons of radio-tracking manatees in this region we are starting to feel a bit more confident about our understanding of how these manatees are utilizing the habitat, and how each individual's behavior differs. If you tracked the manatees with us in the past, you may recall that we learned how very important access to fresh water is to manatees in this region. If you review the maps of manatee locations, you will see that they move between the seagrass beds and inland sites - either Port of the Islands or to the numerous creeks and rivers. These inland sites are the areas where manatees go when they are thirsty. Showing a Preference for Where to Get Freshwater Notice that each manatee often has a preferred inland area to acquire freshwater, and some appear to be very loyal to his or her site, although we do not know why. If you compare the movements seen on the maps for Actual in the two seasons she has been tracked, note that she almost always used Port of the Islands as her freshwater source. Now look at the maps for Santina, in the three seasons that she has been tracked. Santina has a larger range than Actual and often went to Port of the Islands for freshwater as well, but she also occasionally visited the Barron and Ferguson rivers for freshwater. Other manatees were quite devoted to other specific freshwater sources. The Need for Future Study As Restoration Continues There are still many years of work ahead on the restoration. We expect that altered flow of freshwater will affect the environment of this region. We now have a substantial amount to data to show current use of the habitat as a freshwater source, with important feeding areas, and an overwintering site. Just about all a manatee needs! We feel certain that changes to the hydrology of this region will require manatees to change their behavior. Just how they respond is what we hope to discover through continued research. Join Us Again Next Season I hope you will all check in with us next year. We may still be following the movements of these manatees, maybe some new ones as well. We look forward to sharing our data with you, and hope you look forward to learning more about manatees and the habitat they depend on for survival. Thank you for joining us all this season! Copyright 2003 Journey North. All Rights Reserved. Please send all questions, comments, and suggestions to our feedback form