The Yellow-headed Blackbird is said to have one of the worst bird calls. If you want a good laugh, you can listen to it here. The bright yellow color attracts attention. This is a juvenile male Yellow-headed Blackbird. The coloring of the head is somewhat brown and he has a white patch by the wing. Females do not have the white wing patch.
The Least Bittern, on the other hand, is very secretive. She stays hidden among the cattails and her call is very quiet. This is a female Least Bittern. She has beautiful warm brown coloring with a dark patch on her head, back, and around her wings. Least Bitterns can straddle cattails, which allows them to feed in water that would be too deep to wade in.