On the evening of August 7, 2008 I returned to the same bridge on Hwy. 170 in order to attempt continue my observations of predation on the bat colony by Bogertophis s. subocularis.
Approaching the underside of the bridge, I nearly stepped on a three- foot Bogertophis s. subocularis. This snake was the normal color phase. It was actually crawling toward the portion of the bridge that had heaviest population of bats. I hoped the snake would continue on its path toward the underside of the bridge. I suspected it was heading there to forage for the occasional bats that I had seen land in the brush and shrubs at the bridge's edge or perhaps to forage along the guano covered ground under the bridge.
Unfortunately (or perhaps fortunately), the snake decided to take refuge in a small borrow instead (likely in response to my presence). See photo subocularis-15
I thought I would just wait the snake out and hope that it would resume foraging. After waiting awhile, I developed a plan to intervene and increase the odds of the bats coming in range of the burrow entrance. From its concealed position just inside the opening of that burrow, it began feasting on bats. In total, the snake attempted to eat five bats. It subdued and ate the first, third and fourth with no trouble at all (other than some apparent difficulty swallowing their pointy wings). The second bat easily escaped from a poorly secured bite. The fifth bat that the snake attacked put up a frantic struggle and escaped after being firmly bitten and aggressively coiled in a failed attempt at constriction. See photos subocularis-16 through subocularis-26. The snake then showed no apparent interest in a sixth bat. I'm not sure if it had a full stomach, was disturbed by my presence, or was just leery after having a difficult time with the fifth bat.