Tree Swallow Frugivory in Winter

This study assesses, through the first systematic field observations of winter foraging of Tachycineta bicolor (Tree Swallow), whether swallow foraging on the fruits of Morella cerifera (Southern Wax Myrtle) is correlated to air temperature. We observed Tree Swallows in central Florida for 53 days between 3 November 2011 and 14 January 2012. Tree Swallows foraged on Southern Wax Myrtle more often on colder days, producing a statistically significant negative relationship between maximum daily temperature and foraging on Southern Wax Myrtle. Our results also indicated that Tree Swallows ate Southern Wax Myrtle fruit over a broad range of temperatures at which flying insects are also available.