Hummingbirds often feature highly irridescent plumage which only glows brightly when the light hits it at just the right angle - usually when the bird is facing directly towards the viewer and light source. This bright glow is most likely intended to scare rivals when the bird is attacking.

Hummingbirds frequently fight over feeding rights at nectar sources (both natural and man-made) within their territories. These tiny birds weight less than 1/4 ounce (2.5 - 4.5 grams is typical) but are very aggressive and surprisingly tough. Even though these fights appear brutal and dangerous, the birds seldom hurt each other physically, although their egos do seem take a bruising! This scene was filmed in Santa Clarita, California with a high speed HD camera resulting in 240 fps slow motion playback (10x slower than real life speed).