Red Bird - No special power but unusually tough and agile.
Blue Bird - Splits into three smaller birds that can act somewhat individually or in concert.
Yellow Bird - Picks up speed and distance tossed by another or rebounds off objects.
Black Bird - Explodes upon impact. The guy is a walking bomb so be mindful of that explosive radius.
White Bird - Flies around and drops an egg bomb that explodes on impact. Keep an eye on the sky, for this bird is stealthy.
Boomerang Bird - Acts like a pinball/boomrang among enemies. Do not surround this bird. He works best among groups.
Big Brother Bird - No special abilities but destroys materials with ease(
I CAME IN LIKE A WRECKING BALL!). Once he gets going, get out of the way!
Orange Bird - Inflates to a huge size like a balloon for a time, then deflates. Increases its defense or agiity respectively.
Pink Bird - Makes bubbles around it which lifts up or can envelope objects or people. Careful not to let the bubbles get around you. You can still suffocate to death.
Mighty Eagle - The Boss. 'Nuff said.