"Each nest held one to three dead eggs that had cooked on the sand when the human disturbance forced the parents, whose bodies shield their unhatched young from the hot sun, to flee," the release says, citing Katie Barnes, a senior biologist for Birmingham Audubon.
The group observed dozens of eggs that had been stacked in small piles and "arranged decoratively around wide mounds of sand," the release says.
The eggs are tiny — about the size of grapes — and adult birds grow to about 1.4 ounces, AL.com reports.
After discovering the incident, Audubon Society members worked to put up fencing and signs to discourage humans from visiting the area. The group says it believes those efforts have worked.
The island is home to about 1,200 actively nesting least terns and about 600 nests, the release says. Least terns are susceptible to predators like like coyotes and foxes, and the organization says it is monitoring their population numbers.
The Audubon Society says it reported the incident to the U.S. Fish and Wildlife Service. The Department of Justice is leading the investigation, according to the release.