Pollinators keep a later calendar in human-modified landscapes, study finds

Human development may be changing more than where pollinators live — it may also be changing when they are active.

University of Florida researchers at the Institute of Food and Agricultural Sciences (UF/IFAS) found that pollinator seasons shifted later in the year across some of the most human-modified landscapes in the eastern United States.

Using more than 80,000 observations submitted to iNaturalist, UF/IFAS researchers found that pollinator activity began about 22 days later and ended about 21 days later in the most human-modified landscapes compared with the least modified landscapes. Researchers were surprised to learn that their overall season did not become longer, but instead the pollinator calendar shifted later.

The findings, published in Royal Society Open Science, provide one of the broadest looks at how human changes to natural areas may be altering the seasonal timing of pollinators across multiple insect groups, including butterflies, beetles and moths.