These four black-crowned night herons represent our first sighting of the species this season at Nature Boardwalk at Lincoln Park Zoo. Pictured in trees on the island on March 30, they’re most likely the birds that completed their migration fastest, the trailblazers.
Last year, Nature Boardwalk’s black-crowned night heron breeding colony contained more than 200 adults at the peak of breeding season. The species is endangered in Illinois, making them particularly important for Lincoln Park Zoo biologists to track.
The herons have a long history at the pond. Black-crowned night herons typically return to the same breeding sites year after year, often even renovating and reusing the same nests. We should soon see herons gathering up twigs and sprucing up nests for the breeding season ahead—their version of spring cleaning.
As of today, 21 black-crowned night herons have made their way to the island. I will continue to watch for more newcomers in days to come.