NAPA (CBS SF) — A wildlife rescue group in Napa County is looking for the public’s help in finding who is responsible for destroying a colony of nesting cliff swallows and brutally killing dozens of chicks.

The incident happened earlier this week and disturbing photos of the dead chicks and destroyed mud nests were posted on the Napa Wildlife Rescue Facebook page.

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The nests were dotting the walls under the railroad bridge at the Oxbow Commons flood control park in downtown Napa. It appeared that someone used sticks and rocks to destroy dozens of nests and then stomping almost 50 chicks to death, according to the rescue group.

“What they did was they went to each wall and just randomly selected targets, threw rocks at them or batted them down with long sticks …and stomped many of them on the ground as they laid there,” said Napa Wildlife Rescue President John Comisky.

The Facebook post said after the attack, adult swallows were seen swooping down on the empty nests and over their deceased babies on the ground.

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“I reported to Sheriff’s Animal Services, but of course there’s nothing to be done, no way to catch anyone,” said a volunteer quoted on the NWR Facebook page. “It was extra distressing for me as some of the babies I had photographed in the previous days were among the dead.”

It was estimated that a third of the nests at the location were destroyed. The rescue group said it was trying to put the word out to find anyone who may have seen anything to give authorities a lead to investigate.

American cliff swallows normally build their nests clumped together under bridges or alongside mountain cliffs. They are seen across North America and migrate south in the winter along the coastlines.

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