A group of beach volleyball players likely killed hundreds of unhatched birds on a small island near Alabama last month when they moved the delicate eggs to clear the area for their game, officials with the Birmingham Audubon Society say.
The conservation group says the beachgoers moved about 30 Least Tern eggs from the area where they hoped to set up their volleyball net. The group arranged the eggs around mounds of sand away from the net — and in direct view of the harsh sunlight on Sand Island, according to a release from the National Audubon Society.
“It’s really hard to imagine how someone could do that to a little egg,” Katie Barnes, chief biologist for Birmingham Audubon’s Coastal Program, said, according to the group. She adds to PEOPLE: “[Least Terns] are highly sensitive to disturbances such as habitat loss, human recreation, storm surge, and predators.”
Around the makeshift volleyball net were at least 100 abandoned nests (one nest holds at least two eggs), the society reported. Apparently, the commotion from the game scared away the birds’ parents, who use their bodies to shield the eggs from the harmful sun.
Just a few hours in the sun is enough to kill the chicks in the unhatched eggs, wildlife biologist Roger Clay, of Alabama’s Department of Conservation and Natural Resources, told the society. And Barnes told the site that, without their parents to shield them, the eggs likely cooked on the sand.
Researchers Emma Rhodes and Andrew Haffenden came upon the scene on July 10 and said some of the eggs had cracks made by the chicks, indicating that they birds were close to hatching before they died.
“[The players] actually made a little dome of sand and placed the eggs around it to decorate it,” Haffenden told the Associated Press.
Researchers immediately contacted the U.S. Fish & Wildlife Service and the Alabama Department of Conservation and Natural Resources, Barnes told the AP.
Shortly after finding the damage, the conservation group set up signs to let beachgoers know about the federally protected birds, and even set up ropes around the remaining nests, according to the AP.
“Ever since we put the fencing up, everyone has been very respectful,” Barnes told the AP. “We have not seen a human footprint in the area. Boaters have not pulled up to that area.”
Last month, Rhodes and Haffenden first spotted the colony of about 600 nests — which would produce over 1,000 chicks. By Aug. 2, there were only 85 fledglings.
Least Terns are white with black caps. The birds begin nesting in May and usually hatch by July, Barnes told the New York Times of the threatened species.