Eastern Garter and Ribbon Snakes are very common throughout South Carolina; I usually catch several Garters each year here. They will generally be found near water, since Garters mostly feed upon amphibians and fish. As for Bull Snakes, we don't have those, but we DO have Pine Snakes, which are in the same genus, Pituophis, and have pretty much the same behavior. Down in Bluffton, though, you probably won't find any Pines. They like a sandy type of habitat. Further north, into the Grand Strand area, you can find Southern Pines(Pituophis mugitus) and inland in the Sandhills regions you can find some really nice Northern Pines(P. melanaleucus). I've caught some huge Northern Pines just north of where I live, up in Chesterfield County. Pines will hiss loudly and try to bluff you out, just like their western cousins, and they get very large, but tame down quickly. Here's a big female Northern Pine that I caught a few years back crossing US Hwy 1 between McBee and Bethune.

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Thanks, Sharon, for the wonderful photo and reply. We have plenty of sand around here and I've checked around fresh bodies of water for the garters many times. Yes I had great respect for the Denver bullsnakes- they would pose for me while I admired their gorgeous patterns! No dashing off like racers. I did have here a timber rattlesnake hanging out around my birdfeeders in 2013-breathtaking beauty!