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Tarantula Mating Season in the Tri-Valley, California

Photo Credit: @thtgirl

Every fall in the Bay Area, male tarantulas take advantage of cooler temperatures and venture out of their dens to seek out a mate. These fuzzy arachnids might give some people the creeps, but they’re actually completely harmless. Some locals and visitors steer clear of certain Tri-Valley parks during tarantula mating season, while others seek out these eight-legged creatures. 

Here’s everything you need to know about tarantula mating season in the Tri-Valley, including when and where to find them. 

When to See Tarantulas During Mating Season

You can usually expect to see tarantulas out and about starting the end of August and spanning through early November. Mating season, and tarantula sightings, typically peak around mid-October. 

Where to Find Tarantulas During Mating Season

Tarantulas can be found in multiple outdoor recreation areas in the Tri-Valley, but they’re most prominent at Mount Diablo State Park, Del Valle Regional Park, and Sunol Regional Wilderness. Once you’ve arrived, you’re likely to see them crawling on roads, trails, trees and other vegetation in plain sight. 

Naturalist-Led Tarantula Hikes

While visitors are usually able to spot tarantulas on roads and trails without help, multiple organizations host naturalist-led tarantula hikes in our parks to help shed additional light on these interesting arachnids. The East Bay Regional Park District hosts tarantula treks in both Del Valle Regional Park and Sunol Regional Wilderness. Save Mount Diablo and the Mount Diablo Interpretive Association facilitate hikes at Mount Diablo State Park. 

Tips for Tarantula Sightings

  • Tarantulas are naturally harmless towards humans and will usually try to evade us during an encounter. Unless you’re accompanied by a naturalist, keep your distance from these friendly creatures. Beware that if you pose a threat, tarantulas can bite predators to protect themselves.
  • Drive carefully when traveling to and from these parks to see our local tarantulas. From afar, they can appear as small black and brown blobs on the road. 
  • Tarantula sightings happen throughout the day, but they tend to pick up around dusk. For the best chance of seeing one (or more) visit our local parks on cooler days in the afternoon. 

Interesting Tarantula Facts

  • While the tarantulas you’ll see out and about during mating season seem huge in comparison to other insects and arachnids, they’re actually much smaller than their female counterparts who spend most of their time underground.
  • These tarantulas may seem like they’re wandering around aimlessly, crossing roads and trails that may put them in danger, but they actually travel long distances driven by female tarantulas’ pheromones. 
  • Mature male tarantulas who leave their dens in search of a mate can be anywhere between 5-10 years old. Once they do find a mate, they are either eaten by the female tarantula or they die within weeks or months afterwards.

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