On October 2, 22 adult rattlesnakes and 59 babies preparing for hibernation were removed from beneath a mountainside home in Santa Rosa, California, AP News reports. 

Director of Sonoma County Reptile Rescue Al Wolf pulled off the massive rescue, which took nearly four hours and required him to crawl under the house on his hands, knees and stomach, turning over more than 200 small rocks as he went. 

The woman who owns the house called for Wolf to investigate after she saw snakes making their way beneath her residence. When Wolf arrived, he immediately found a rattlesnake, and he continued to encounter one after another; he climbed out from under the house, grabbing buckets, a 24-inch snake pole and long gloves to finish the job. 

Wolf said all of the snakes were Northern Pacific snakes, the only venomous snakes found in California. 

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Wolf has been rescuing snakes for 32 years and has been bitten 13 times. Typical calls involve taking care of only one or two snakes. “I thought, ‘Oh, good, it was a worthwhile call,'” Wolf told AP News on Friday. “But I was happy to get out because it’s not nice; you run into spider webs and dirt, and it smells crappy and it’s musty and you’re on your belly and you’re dirty.”

Since the inital rescue, Wolf has returned twice and extracted 11 more snakes, and he has plans to search beneath the house again before the end of the month, as the den site is particurlarly appealing to the snakes. Wolf said the rocks beneath the residence and the house itself offer “double insulation” from winter rains. 

Rattlesnakes generally hiberante from October to April, seeking rocks and warm places, and they’ll return to those locations year after year. 

Wolf sets the snakes free in the wild away from people and sometimes on private property when ranchers request them to control pests. 

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