Dam spiders ... hairy, huge, and scary

When I first saw one of these huge hairy spiders in Barker Reservoir a couple or so years ago, I thought it might have been set loose by someone who no longer cared to have a tarantula as an exotic "pet". These hairy critters are about 3-4 inches long (leg-span-wise) and are now all over the dam. Highly visible on the crushed rock, but they move around the grass too and dangle from stalks, as seen in pic above.

They are probably on the Dam because the reservoir got flooded and they went looking for higher ground. Another theory is that it's mating season and these are mature males out and about looking for a willing female (who will then eat him after the intimate encounter. -- Or so the story goes.).

If this is an invasive species, it sure has adapted very well, and is breeding and multiplying. There were at least five specimen, all out on the gravel road on top of Barker Dam near the Briar Forest (Noble Road) ramp. Noble Road trail is still under water, though the flooding is now receding with record-high release of held-back storm water into Buffalo Bayou at the flood gate for past few days.

It would be good to know if they are venomous. Various internet article say that a tarantula bite is not too bad unless you are allergic to them. There are plenty of people who keep them as low-maintenance pets. And they live long lives. At least the females. I'd rather not have them crawl on my hand. I'd rather observe them in the wild and not have them around the house.

Barker Dam South of Briar Forest / Noble Road 

Sunset at Barker Reservoir June 9, 2015