A Black-crowned Night-Heron (Nycticorax nycticorax) was observed bill-vibrating, a foraging behavior in which the heron submerged its bill tip in the water and rapidly opened and closed its mandibles creating a disturbance of the water surface. This fish-luring behavior has previously been reported once for a Black-crowned Night-Heron, and for several other heron species. This behavior may be used when algal growth or other water obscuring agents interferes with a heron's vision making visual foraging techniques problematic, and may have enhanced effectiveness because the algae make the predator less likely to be seen.