Habitats Also Influence How Egrets Use a Space
Great Egrets foraging strictly in freshwater used around half the area of those using tidal sites. Changing tides shift the areas available to foraging egrets throughout the day, so may dictate foraging opportunities in a way that freshwater systems do not. But there may be more effects, such as shape of coastline relative to roost or colony sites, or relative food availability at play.
By collaborating and combining data with colleagues, we found consistent patterns in movement by Great Egrets living in very different parts of North America. As parents fly farther to get more food for their growing chicks, they expend more energy and are at greater risk of predation or accidental injury. When they aren’t raising young, they can travel more widely—or even migrate—to find the best foraging habitat.
These results improve our understanding of the scale of landscape conservation needed for Great Egrets to continue to thrive: only protecting wetlands near breeding sites may not provide sufficient habitat for these birds throughout the year.
To read additional research from Audubon Canyon Ranch, please visit Scientific Publications.