FREMONT (CBS/AP) – Park rangers in Fremont are trying to control a spring pest—the Canada goose.

Rangers in the East Bay Regional Park District are using a form of birth control by dipping clutches of eggs in corn oil to suffocate the embryos and then returning them to the nest so the mother won’t lay more.

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KCBS’ Matt Bigler Reports:

Rangers said without some form of control, the big geese would overpopulate and their droppings would threaten water quality at local lakes.

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Populations of the honking waterfowl have taken off in California because of an abundance of food and nesting areas and an absence of natural predators.

Some places have reduced their numbers by allowing hunting or chasing the geese away with dogs.

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