Female Tricolored Blackbird (7297782170)

Description:

Summary[edit] Description: Female Tricolored Blackbird (Agelaius tricolor) with brood patch. Changes in hormone levels cause down feathers on the bird's stomach to become very loose. The tissue in the stomach area swells and the blood vessels of the skin expand. These changes make the bird's brood patch almost as hot as the body's interior and good for incubating eggs. (Cindy Sandoval/USFWS). Date: 26 May 2012, 09:14. Source: Female Tricolored Blackbird. Author: Pacific Southwest Region USFWS from Sacramento, US.