California Bats in Fall: Preparing for the Quiet
As the nights get cooler in September and October, California's bats begin their preparation for winter. The peak of summer is over, but the bats are busy fattening up or starting their migration south. It is a quieter time, but still full of activity if you know where to look. Check our [California bat](/wildlife/california/bat) trunk page or the [best time to see bats in California](/wildlife/california/bat/best-time) for details.
By Tim, founder of Easy Street Markets. I maintain the wildlife database and verify every animal and source myself. Updated July 1, 2026.
- 3
- species recorded
- July, August, September
- peak months
Real sighting data, source iNaturalist
7,270 verified observations on iNaturalist of bat have been recorded in California, most often in July, August, September.
As the nights get cooler in September and October, California's bats begin their preparation for winter. The peak of summer is over, but the bats are busy fattening up or starting their migration south. It is a quieter time, but still full of activity if you know where to look. Check ourCalifornia battrunk page or thebest time to see bats in Californiafor details.
Do California bats migrate in the fall?
Yes, several species like the Mexican Free-tailed Bat head south for the winter. This migration is a massive undertaking, and they often travel long distances to find the perfect wintering grounds in warmer climates.
Where do they go for the winter?
Those that stay in California seek out caves, abandoned mines, and other frost-free spots. These locations provide the stable temperatures they need for a successful hibernation through the colder months.
What do they eat in late October?
They focus on late-season moths and other large insects to build up their fat reserves. This extra weight is crucial for survival during the months when food is scarce and they are in a state of torpor.
Is fall a good time for bat watching?
It is your last chance to see them before they enter hibernation or finish their migration. After fall, you can learn about theirwinter restor look back at theirpeak summer activity.
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Frequently asked questions
Do California bats migrate in the fall?+
Yes, several species like the Mexican Free-tailed Bat head south for the winter. This migration is a massive undertaking, and they often travel long distances to find the perfect wintering grounds in warmer climates.
Where do they go for the winter?+
Those that stay in California seek out caves, abandoned mines, and other frost-free spots. These locations provide the stable temperatures they need for a successful hibernation through the colder months.
What do they eat in late October?+
They focus on late-season moths and other large insects to build up their fat reserves. This extra weight is crucial for survival during the months when food is scarce and they are in a state of torpor.
Is fall a good time for bat watching?+
It is your last chance to see them before they enter hibernation or finish their migration. After fall, you can learn about theirwinter restor look back at theirpeak summer activity.
Keep exploring
More places to see bat
More wildlife in California
Common questions about bats