Yeah, they are rather clumsy. A fellow I know at my lab is conviced these feed mainly on wading birds, which, due to their hunting habits, have to remain still to ambush their prey. I do not know of a study on host range of these guys, but it is hard to imagine that a mammal would put up with a concerted attack. The exception of course is I, who stuck my arm in a cage of 25 of these to try and get them to feed and lay eggs. 7 fed and they all died before ovipositing.
Yes, they are native.

Beautiful image! Is she drilling into a boot or something? Geez, how long will it be before we'll all have to wear lead clothing to stop them?:-)

Yeah, they seem to like my shoes. These are pretty easy to swat, but if you are say, out in the field, with no bug repellent, trying to download a weather station, holding a laptop in both hands etc. they can be pretty annoying.

I hope the ones that got me died.
Am I correct in thinking they are the largest mosquitoes in the area?

No, but they are the largest biting ones. The largest is Toxorhynchites rutilis, the Elephant Mosquito. These guys just hang out in containers and eat other mosquito larvae. As adults they eat nectar.
The Psorophora species also eat other mosquito larvae, but are good biters as well.

Thanks for the info.