Our Liviiti^ Rc'Mtnni'.s — C(nisttil tt Murine Ecosystems 



3(59 



Future 



Population and life-history information sug- 

 gests that the potential long-term viability of the 

 Florida manatee population is good, provided 

 that strong efforts are continued to curtail mor- 

 tality, habitat quality is maintained or improved, 

 and steps are taken to offset potential catastro- 

 phes. 



References 



Ackerman. B.B. Ongoing manatee aerial survey pro- 

 grams — a progress report. In T.J. O'Shea, B.B. 

 Ackerman. and H.F. Percival, eds. Population biology of 

 the Florida manatee {Trichechus immatus latirostris). 

 National Biological Service. Biological Rep. Series. In 

 press. 



Ackerman. B.B.. S.D. Wright. R.K. Bonde. D.K. Odell, and 

 D.J. Banowetz. Trends and patterns in manatee mortality 

 in Florida. 1974- 1W2. In T.J. O'Shea. B.B. Ackeniian. 

 and H.F. Percival. eds. Population biology ot the Florida 

 manatee (Trichecbus manatiis latirostris). National 

 Biological Service, Biological Rep. Series. In press. 



Beck. C.A.. and N.B. Barros. 1991. The impact ot debris on 

 the Flonda manatee. Manne Pollution Bull. 22( 10):-'if)8- 

 ."^lO. 



Beck, C.A., and J. P. Reid. An automated photo-identiTica- 

 tion catalog for manatee life history studies. /;; T.J. 

 O'Shea, B.B. Ackerman, and H.F. Percival. eds. 

 Population biology of the Florida manatee (Trichechus 

 manatus latirostris). National Biological Service. 

 Biological Rep. Series. In press. 



Busby. D.S.. and R.W. Vimstein. 199.^. E.xecutive summary. 

 Pages iii-viii in L.J. Morris and D.A. Tomasko, eds. 

 Submerged aquatic vegetation and photosynthetically 

 active radiation. Special Publ. SJ9-^-SPl.\ St. Johns 

 River Water Management District, Palatka, FL. 



Fernald. E.A., E.D. Purdum, J.R. Anderson. Jr., and PA. 

 Krafft. 1992. Atlas of Flonda. University Press of 

 Florida, Gainesville, FL. 280 pp. 



Ganott, R.A., B.B. Ackerman, J.R. Gary, D.M. Heisey, J.E. 

 Reynolds III, RM. Rose, and J.R. Wilcox. 1994. Trends 

 in counts of Florida manatees at winter aggregation sites. 

 Journal of Wildlife Management 58(4):642-654. 



Lefebvre. L.W.. B.B. Ackerman, K.M. Portier, and K.H. 

 Pollock. Aenal surveys for estimating manatee popula- 

 tion size and trend — problems and prospects. In T.J. 

 O'Shea, B.B. Ackerman, and H.F. Percival, eds. 



Population biology of the Florida manatee {Trichechus 

 tuanatiis latirostris). National Biological .Service, 

 Biological Rep. Series. In press. 



Lewis, R.R., III. 1987. The restoration and creation of sea- 

 grass meadows in the Southeast L'nited States. Pages 

 l,s.1-17.^ in M.J. Durako, R.C. Phillips, and R.R. Lewis 

 III, eds. Proceedings of the Symposium on Subtropical- 

 tropical Seagrasses of the Southeastern United States, 1 2 

 August 198.'). Florida Marine Research Publications 

 Number 42. St. Petersburg. FL. 



Marmontel, M. Age and reproductive parameter estimates 

 in female Florida manatees. In T.J. O'Shea, B.B. 

 Ackerman, and H.F. Percival. eds. Population biology of 

 the Florida manatee {Trichechus manatus latirostris). 

 National Biological Service, Biological Rep. Series. In 

 press. 



O'Shea, T.J., and W.C. Hartley. Longitudinal studies of 

 manatee reproduction and early age survival at Blue 

 Spring, upper St. Johns River, Florida. In T.J. O'Shea, 

 B.B. Ackeniian, and H.F. Percival, eds. Population biol- 

 ogy of the Florida manatee (Trichechus manatus 

 latirostris). National Biological Service, Biological Rep. 

 Series. In press. 



O'Shea. T.J., and C.A. Langtimm. Adult survival estimates 

 for Florida manatees at Crystal River, Blue Spring, and 

 the Atlantic coast. In T.J. O'Shea, B.B. Ackerman, and 

 H.F. Percival, eds. Population biology of the Florida 

 manatee (Trichechus manatus latirostris). National 

 Biological Service, Biological Rep. Series. In press. 



Rathbun? G.B., J.P Reid. R.K. Bonde. and J. A. Powell. 

 Reproduction in free-ranging Florida manatees 

 (Trichechus manatus latirostris). In T.J. O'Shea, B.B. 

 Ackerman, and H.F. Percival. eds. Population biology of 

 the Flonda manatee (Trichechus manatus latirostris). 

 National Biological Service, Biological Rep. Series. In 

 press. 



Reynolds, J.E., 111. and JR. Wilco.x. 1994. Observations of 

 Florida manatees (Trichechus manatus latirostris) 

 around selected power plants in winter Marine Mammal 

 Science 10(21:163-177, 



USFWS. 1989. Florida Manatee (Trichechus manatus 

 latirostris) Recovery Plan. Prepared by the Florida 

 Manatee Recovery Team for the U.S. Fish and Wildlife 

 Service, Atlanta, GA. 98 pp. 



Wnght, S.D., B.B. Ackerman, R.K.. Bonde, C.A. Beck, and 

 D.J. Banowetz. Analysis of watercraft-related mortality 

 of manatees in Flonda, 1979-1991. In T.J. O'Shea, B.B. 

 Ackerman. and H.F. Percival, eds. Population biology of 

 the Florida manatee (Trichechus manatus latirostris). 

 National Biological Service, Biological Rep. Series. In 

 press. 



For further information: 



Lynn W. Lefebvre 

 National Biological Service 



Sirenia Project 



412 NE 16th Ave., Rm2,S0 



Gainesville, FL 32601 



T 



he Gulf of Mexico's coastal wetlands are of 

 special interest because the gulf is an excep- 

 tionally productive sea that yields more than 1 . 1 

 billion kg (2.5 billion lb) of tlsh and shellfish 

 annually and contains four of the top five fish- 

 ery ports in the nation by weight (U.S. 

 Environmental Protection Agency 1988). The 

 volume of commercial shrimp landings in the 

 gulf has been statistically related to the areal 

 coverage of gulf coastal wetlands (and seagrass 

 beds) that provide crucial nursery habitat to the 

 young (Turner 1977), Coastal wetlands (partic- 

 ularly salt marshes and mangroves) and associ- 

 ated shallow waters function similarly in sup- 

 port of many fish species of commercial interest 

 (Seaman 1985). The gulf wetlands are also well 

 known for their large populations of wildlife, 

 including shorebirds, colonial nesting birds, and 



75% of the migratory waterfowl traversing the 

 United States (Duke and Kruczynski 1992). The 

 extensive coastal wetlands that remain along the 

 gulf make up about half of the nation's total 

 wetland area (NOAA 1991). 



General Trends 



The National Oceanic and Atmospheric 

 Administration (NOAA 1991) examined the 

 areal extent and distribution of gulf coast 

 coastal wetlands in the mid-1980's by using aer- 

 ial photographs and maps from 1972 to 1984 

 (28% from 1979 and 42% from 1980 or later). 

 Summaries of NOAA's data are shown in the 

 Table for three wetland categories: marshes 

 (fresh, brackish, and salt marshes), estuarine 



Gulf of 

 Mexico 

 Coastal 

 Wetlands: 

 Case Studies 

 of Loss Trends 



by 



James B. Johnston 



Mary C. Watzin 



John A. Barras 



Lawrence R. Handley 

 National Biological Service 



