During the summer, the veery thrush birds, with their brown feathers and white bellies, will embark on a long journey to South America by crossing the Gulf of Mexico and the Caribbean Sea. The migration of a small songbird weighing 30 grams is perilous, and if a hurricane intersects their path, some of the birds may not survive.
However, each hurricane season varies, and still veery birds have been found to be connected to global climate cycles which enable them to predict the severity of a season.
According to a study conducted by Christopher Heckscher, an ecologist at Delaware State University in 2018, the migration patterns of veery birds from Delaware to South America have consistently been able to predict the severity of the Atlantic Basin hurricane season for the past twenty years.
In difficult years, the veery’s would finish their breeding season earlier and migrate to South America earlier. In more favorable years, the birds would stay in eastern North America for a longer period of time.
From 1998 to 2016, the researcher and his team monitored birds and found that the behavior of veeries was consistently reliable in predicting whether hurricane activity in the United States would be higher or lower than average.
After Heckscher’s study was published, the birds have been consistently accurate in predicting Atlantic hurricanes. Although it is still uncertain what they are predicting for 2023, they have been as reliable as meteorological models in three out of the last four hurricane seasons.
According to Heckscher, birds gather information about weather patterns from their wintering grounds in South America, where the weather conditions that affect hurricane seasons develop before a hurricane is formed.
Exactly how the veeries’ “predict” hurricane seasons may result from small changes in regular, global cycles like El Niño and La Niña events. Bird migrations, such as those undertaken by veeries, have developed gradually over many centuries as birds detect and respond to anticipated weather modifications and we humans have yet to understand this data from nature.
Reference- Journal Scientific Reports, National Geographic, The Cornell Lab website, BBC, Nature