Synoptic Survey Conditions for Winter 2013

Due to warmer than average weather, the Florida Fish and Wildlife Conservation Commission did not conduct the annual statewide manatee synoptic survey this winter.

The Florida Fish and Wildlife Conservation Commission (FWC) did not conduct the annual statewide manatee synoptic survey in winter 2013 because of warmer than average weather. Warm winter weather conditions also led to no survey in 2012.

The FWC conducts synoptic surveys to meet the state's requirement for an annual count of manatees in Florida waters, weather permitting. The goal of the survey is to achieve the highest minimum count by surveying areas where researchers expect to see the most manatees. Researchers need specific weather conditions to successfully conduct these surveys. The state developed these requirements because surveys conducted in less than favorable conditions produce low counts, as many animals may be missed. Conditions this winter never met the state's minimum requirements.

The FWC attempts to conduct annual manatee synoptic surveys to provide researchers with a snapshot of manatee distribution around the state of Florida at the time of the survey. This survey is a minimum count and cannot be used to estimate population size or assess long-term population trends. In the last synoptic survey, conducted in 2011, researchers counted 4,834 manatees.

Researchers conduct this interagency survey during the coldest months of the year, usually between January and early March. When temperatures are low, manatees move to warm-water sites such as natural springs, thermal discharges from power and industrial plants, and deep canals. During synoptic surveys, teams of observers fly over warm-water sites and other areas to count the animals. Ideally, researchers conduct synoptic surveys during cool weather, following a prolonged period of cold weather, with low winds and bright sunshine. The FWC will only conduct the survey if conditions meet all of the following requirements simultaneously:

  1. Air temperatures forecast to be less than or equal to 49 degrees Fahrenheit near most major manatee aggregation sites on at least three of five days prior to the survey.
  2. Water temperatures below 68 degrees Fahrenheit near most major manatee aggregation sites.
  3. No winds forecast above 15 knots (17 mph) in the entire survey area on survey days.
  4. No sky conditions forecast as "mostly cloudy" or "rainy" in the entire survey area on survey days.

The FWC continues to work toward improving methods to produce surveys that are more statistically accurate and less dependent on very cold weather conditions. Researchers are currently improving the analytical steps used to estimate abundance. Following successful testing, the new methodology will replace the existing synoptic survey methods.  



FWC Facts:
Red tides have been documented along Florida's Gulf coast since the 1840s and likely occurred earlier. Fish kills around Tampa Bay were mentioned in the logs of Spanish explorers.

Learn More at AskFWC