In 2001, California began using helicopters to scatter poisoned grain across Anacapa Island after black rats devoured up to 70% of seabird eggs

Black rats have been slowly dominating Anacapa Island, which is a chain of rugged volcanic islets off Southern California that acts as one of the West Coast’s most important seabird nesting grounds. They were introduced accidentally by ships in the early 1900s, spread across the island, and began feeding on eggs, chicks, and native wildlife.

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