Wading bird numbers in the Florida Everglades are driven by water patterns that play out over multiple years according to a new study by the U.S. Geological Survey and Florida Atlantic University. Previously, existing water conditions were seen as the primary driving factor affecting numbers of birds, but this research shows that the preceding years' water conditions and availability are equally important.
"We've known for some time that changes in water levels trigger a significant response by wading birds in the Everglades," said James Beerens, the study's lead author and an ecologist at USGS. "But what we discovered in this study is the importance of history. What happened last year can tell you what to expect this year."
From 2000 to 2009, scientists examined foraging distribution and abundance data for wading bird populations, including Great Egrets, White Ibises, and threatened Wood Storks. To do the research, they conducted reconnaissance flights across the Greater Everglades system, an area that includes Big Cypress National Preserve and Everglades National Park. They found climate and water management conditions going as far back as three years influenced current bird population numbers and distribution.