SAN DIEGO -- A new breed of spider is showing up around San Diego, and experts say the number of poisonous brown widow spiders -- which are not native to Southern California -- continues to grow.

Brown widow spiders have made the Webb family's back yard their home, and they refuse to leave.

"It's just creepy … when they start moving into the house that's when I move out," said Kelli Webb.

The Webbs have their very own spider colony on their property. The spiders are in their trash cans, flower pots and patio furniture.

"A couple weekends ago we found over 100," said Webb. "They're everywhere."

Originally from South Africa, the brown widow spiders were first spotted in San Diego in 2004. Experts say they have multiplied by the thousands and have been found as far north as Carlsbad and as far south as Imperial Beach.

The Webbs have a 3-month-old son and they think twice about spending any time in their back yard.

The brown widow spiders are poisonous, and in the first 15 minutes of 10News' visit more than a dozen were caught.

The brown widow's venom is more potent than the venom of its cousin, the black widow, and one bite can send a person to the hospital.

The spiders also multiply quickly, with eggs hatching in 20 days. One egg could contain 35 spiders.

"If you don't kill that or if you don't eliminate it somehow … now I hate to kill things but they're going to keep multiplying," said Webb.

San Diego County's bug experts say they are now seeing brown widows inland instead of just in ocean communities.

For now, the Webb family hopes the spiders won't build any more webs on their property, so their little boy can play outside without fear.

Spider bites are not required to be reported to the county, so no statistics were available.