| | (Click on photo for larger image.)  (FWC photo by Tom Reinert)
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Updated Jan. 27, 2009 What is a synoptic survey? A manatee synoptic survey is a count of manatees over a broad area. Researchers fly over areas where they expect to see the most animals. The surveys are conducted in the winter, when more manatees are present at the warm-water aggregation sites around the state. Synoptic counts give researchers a minimum number of manatees in Florida waters. They also provide a snapshot of manatee distribution around the state in the winter. Is the survey a population estimate? No, it is a minimum count of manatees in Florida waters. How does the FWC use survey results? These results are a minimum count of manatees in Florida waters. They also provide a snapshot of manatee distribution around the state in the winter. They provide researchers with the minimum number of manatees in Florida waters at the time of the survey on the days the survey was conducted. Managers use the information on manatee distribution to help make informed management decisions. Top of page How often does the FWC conduct the surveys? The FWC conducts the synoptic survey at least once a year, weather permitting. These aerial surveys are conducted in accordance with section 379.2431(4)(a), Florida Statutes, which requires an annual population census. Top of page Why did the FWC not fly the synoptic survey in 2008? Weather conditions did not meet the FWC's requirements to fly the survey last year. This was only the third time in 18 years that the agency was unable to fly the survey. The FWC also did not conduct the survey in the winters of 1993 and 1994. Top of page What conditions do scientists prefer for conducting synoptic surveys? The prescription for a favorable survey includes cool weather following a prolonged period of cold weather (usually following multiple cold fronts), low winds and bright sunshine. Weather conditions and manatee behavior during the survey have a large effect on the synoptic counts. Weather requirements to conduct the survey: - Air temperatures forecasted to be no higher than 49° F near most major manatee aggregation sites on at least three of five days prior to the survey.
- Water temperature below 68° F near most major manatee aggregation sites.
- On the survey days, no winds forecasted above 15 knots in the entire survey area.
- On survey days, no sky conditions forecasted as "mostly cloudy" or "rainy" in the entire survey area.
Top of page How do the survey results compare to manatee mortality statistics? The manatee synoptic survey results can not be compared to mortality statistics. The synoptic survey provides a minimum count, not a population estimate, since we don't know how many animals observers may have missed during the survey. The mortality data provide all the information we have about dead manatees, both recovered and reported. Some carcasses may go unreported, so the mortality information may not provide the full picture of individuals lost from the population. Both provide useful information, but comparing them is not an accurate way to reach conclusions about the status of the population. Top of page Are any improvements planned for the synoptic survey? Currently, the FWC is testing new survey methods and evaluating their results. As part of the development of any new study plan, the FWC must test methods before applying the approach to address a particular goal. The new methods involve surveying within all known winter manatee habitat, allowing biologists to estimate the number of animals not counted, and making the survey less dependent on very cold weather conditions. The FWC's goal is to implement statistically sound methods to estimate the Florida manatee population and monitor trends, rather than provide only a minimum count under the current synoptic method. Top of page Is the FWC pleased with the results of the 2009 manatee synoptic survey? Yes. An increase in the minimum known number of an endangered species is always good news. |