Black bears near Lake Tahoe, California, have been digging at the foundations of peoples’ homes — and according to a local bear conservation group, the fault may lie with the homeowners.

“Bears love rodent poison,” explained BEAR League on Facebook. “To a bear, this poison smells like candy, just as it does to mice…Just in the past three days, the BEAR League has answered nine calls from Tahoe residents who have bears intently digging and ripping to get under their homes. After asking a few questions, it was discovered that every single one of them had mouse bait under their house.”

The organization says that professional pest control services often place rodent control “bait stations” under peoples’ homes. But in bear country, this practice can have unintended consequences in the form of thousands of dollars in damages from bears clawing foundations and easily tearing up crawl space doors. The poison is bad for the bears, too.

“Adult bears usually don’t die from ingesting it, but cubs sometimes do,” wrote BEAR League. “Ignore this warning at your peril…[It’s] best not to invite [bears to your home].”

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The Lake Tahoe area is notorious for its bear activity. According to the San Fransisco Chronicle, the Tahoe Basin is considered the “Bear Capital” of California and supports a dense population of around 300 black bears. Black bear hunting is legal in California, though hunting bears over hounds was banned in 2013.