For at least five years, Rick Vetter at UC Riverside has been reporting a trend – Black Widows are being pushed out by their less-venomous cousin, the Brown Widow spider.
Steve Notes:
Black Widows are native to the United States, while Brown Widows are from Africa. Made their way over here via trade through Florida. I wholeheartedly agree. I’ve noticed this trend first hand. Middle Ga used to have a huge population of black widows.
Here’s a clip from Rick explaining how the brown widows are pushing out the black widows.
They’re not physically attacking the Black Widows, they’re just making more babies.
This is a good thing and it’s a bad thing.
Here’s Rick talking about the impact of this take-over
Is this hurting the ecosystem? “The brown widows are probably doing the same ecological task as the black widows,” Vetter says, “so I don’t think you’re going to see a great ecological Armageddon happening. But we never like to see a native displaced by a non-native.”
The black widow population, Vetter says, “has probably taken a hit from the brown widows, but the black widows are still very common in agricultural areas, where the brown widow does not seem to establish.”