Birds often change their feather colors seasonally through a process called molting. This color change typically serves two main purposes:
- Breeding season display to attract mates
- Camouflage during non-breeding seasons
During breeding season, many male birds develop brighter, more vibrant plumage to attract females. For example, male American Goldfinches transform from dull brown in winter to bright yellow in spring. This process is influenced by hormones and triggered by changing day length. After breeding season, birds molt again to develop more cryptic coloring that helps them blend into their environment and avoid predators.