Yes, I was bitten on the ankle by a chihuahua once- and it's no picnic!
But these little guys probably couldn't have REACHED our ankles as we peddled. Besides, they were actually covering more distance exploding up and down vertically than moving towards us, so we sized their intentions up pretty easily. ...I keep envisioning them in one of those old fashioned Jiffy Pop things you shake over the stove.