The cassowary, known for aggressive behavior and lethal kicks, is a dangerous bird with powerful legs and sharp claws, reaching speeds of up to 30 mph in encounters with humans.

1. Cassowary (Casuarius)

Ostriches, flightless but speedy at 45 mph, use strong legs and sharp claws for self-defense, posing a threat if they feel provoked.

2. Ostrich (Struthio camelus)

Like ostriches, emus are flightless, territorial, and can be aggressive, especially during breeding. With powerful legs and sharp claws, they run at high speeds, posing a potential danger.

3. Emu (Dromaius novaehollandiae)

The lammergeier, while not physically harmful, drops bones from heights, posing a potential threat to those below, causing possible injuries.

4. Lammergeier (Gypaetus barbatus)

Nocturnal and powerful, great horned owls can attack larger animals. Though not usually a threat to humans, they may become aggressive if provoked or if their nests are threatened.

5. Great Horned Owl

Barred owls, generally not harmful, may act defensively during nesting. Occasionally, they've been reported attacking humans near nests or perceived threats to their young.

6. Barred Owl (Strix varia)

These birds vary in danger levels, some with direct threats from physical attributes, others posing risks in specific situations or feeding behaviors. Humans should exercise caution and respect when interacting with wildlife.