Every fall, mature male tarantulas leave their burrows and go looking for a mate, and a few East Bay parks are good places to see them. The season runs from about late August through early November, and Visit Tri-Valley says sightings typically peak around mid-October. That means there's still a little time left this year.

Where to look

Visit Tri-Valley says tarantulas are most common at Mount Diablo State Park, Del Valle Regional Park and Sunol Regional Wilderness, where they can turn up on roads, trails and vegetation in plain sight. California State Parks also lists Mount Diablo among the state parks where people most often spot them.

When to go

State Parks says the males are most active at night. Visit Tri-Valley says sightings pick up around dusk and suggests cooler afternoons for the best chance. That timing matters at Mount Diablo: its gates open at 8 a.m. and close at sunset, and State Parks says visitors should be in their vehicles and heading out by sunset to avoid getting locked in. Once clocks fall back on Sunday, Nov. 1, sunset will come about an hour earlier by the clock.

Mount Diablo's vehicle day-use fee is $6, or $10 at peak times, according to State Parks. Dogs aren't allowed on its trails or fire roads.

What you're seeing

The wandering tarantulas are males, often 5 to 10 years old, following pheromones released by females, according to State Parks. They can travel long distances, sometimes up to 20 miles, and may walk for two to three months before finding a mate. Females live much longer, 20 to 25 years or more, and stay in or near their burrows.

After mating, State Parks says, females often eat the male unless they've already eaten or have plenty of food. Visit Tri-Valley notes the males either get eaten or die within weeks or months.

How to watch

  • Keep your distance. State Parks says local tarantulas are shy and slow, and a bite from one that's badly provoked is, for most people, milder than a bee sting.
  • Don't pick them up or poke at burrows, and skip flash photography. State Parks also says not to shine a flashlight directly on them.
  • Drive slowly. Visit Tri-Valley says that from a distance they can look like small black or brown blobs on the road.
  • Log your sighting on iNaturalist, which State Parks says helps researchers track populations.