Which bird uses bait to lure fish, making it a tool user?

The green heron uses bait to lure fish, making it a tool-using bird. It may drop bread crusts, insects, feathers, leaves, or other small objects onto the water's surface. Fish investigate the apparent food, allowing the heron to seize them when they approach.

Green herons usually hunt by standing motionless in shallow water or beside ponds and streams. Bait-fishing is unusual among birds because the heron deliberately alters the normal hunting situation: instead of waiting for fish to pass, it creates a lure that brings prey within striking range. This behavior is commonly cited in discussions of animal tool use.

The green heron is not the only bird associated with bait-fishing. Its close relative, the striated heron, has also been recorded using bait, and other birds may use food items to attract prey. However, among the choices given, green heron is the canonical answer. It is also sometimes confused with the great blue heron, which is a larger wading bird that generally hunts by visually stalking or spearing prey rather than baiting fish.