Wading Bird Nesting Population in South Florida Up Significantly
(Washington, D.C., April 16, 2010) According to a report from the South Florida Water Management District (SFWMD), which includes Everglades National Park, the number of nests of wading birds, such as herons and egrets, in the district are estimated to have more than quadrupled between 2008 and 2009.
The estimated total number of wading bird nests in South Florida was 77,505 in 2009, which eclipses the number of nests recorded during the previous high recorded year of 2002 by about 8,000 nests, and represents the largest nesting effort since the 1940s.
Increases in nesting occurred for most wading bird species and especially for the endangered Wood Stork. Approximately 6,452 Wood Stork nests were recorded in 2009, about four times the number of nests over the average of the past decade.
“These numbers are certainly a welcome one-year finding, but we must be mindful of the long-term forecasts of great concern for birds that depend on wetlands across the United States. The 2010 State of the Birds Report, co-authored by the U.S. Fish and Wildlife Service, American Bird Conservancy (ABC) and others, tells us that waterbird populations will likely be hard hit by climate change impacts as changes in temperature and rainfall reduce the quantity and quality of wetlands,” said George Wallace, Vice President for the Oceans and Islands Program of ABC.
According to the SFWMD report, the 2009 survey numbers may be the result of extensive drought conditions in recent years that reduced predatory fish densities, allowing crayfish and small fish populations, which are food sources for wading birds, to increase in size and abundance. “Given the magnitude of the wading bird increases, one cannot rule out influxes of birds from other locations, where water conditions and prey supplies were not as favorable to nesting birds as they were in south Florida,” Wallace added.
Scientists also found that wading birds appeared to increase nesting activity on the recently restored section of the Kissimmee River floodplain. Over 1,500 nests were recorded there, which is considerably greater than the six nests that were recorded there in 2008 and greatly surpasses the previous high count of 637 nests in 2006.
Additional highlights in the report include:
1. The 2009 season represented an 83 percent increase over the average of the last nine seasons.
2. The wading bird nest count around Lake Okeechobee, 8,169 nests, was the fourth highest count since aerial surveys began in 1957.
3. White Ibis nest numbers were double the average of the past nine years.