Hm, it’s a black spider with red dots on its back:
Pictures of Gretchen Quarterman with a black widow spider at Okra Paradise Farms by John S. Quarterman, Lowndes County, Georgia, 20 September 2011.
-jsq
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What’s that on the fence post?
It moves fast:
Doesn’t look like your typical Black Widow, which usually has more spindly legs in my experience and red hourglass on its underside.