But the biggest draw seemed to be the cow-nosed stingrays. The way rays fly through the water is so different from anything else that they look like aliens, with a mouth on their underside always curved into a smile. As they circled their tank, the rays would flail against the tank wall, splashing the delighted gawkers. I also noticed, however, that the snouts on some were raw and bleeding where they kept rubbing along the glass. It looked like the kind of manic behavior that makes other zoos so troubling, so recently I gave Paula Powell, the aquarium's director of husbandry, a call. She assured me that the rays just get excited when they see people. "To them, people mean food," she says. Powell says the rays are closely monitored and treated if their scrapes get too big.
Then she unexpectedly suggested another explanation: rough sex play. "During mating season the males tend to become very aggressive toward the females," she said. Apparently, some of the wounds on the rays were likely inflicted by each other in the course of getting their ray groove on. Now that perpetual smile begins to make sense.--Rick Kennedy