The western black widow, the only widow species native to Colorado and the only spider species that can harm a person with its venom, is entering the reproductive phase of its life cycle ...

Fortunately, fatalities are fairly rare; the spiders are nonaggressive and bite only in self-defense, such as when someone accidentally sits on them. The animals most at risk from the black widow' ...

They name two kinds of spider: a black widow and a brown recluse ... rarely have serious complications. Kids and people older than 60 are most at risk of a life-threatening response to venom.