Species: Oregon Junco
Most recent capture date: 6/15/2021
Age: less than 4 months old

Notes: In juvenile plumage, Oregon Juncos are streaky brown. Soon this bird will molt into the distinctive gray/black hood and cinnamon flanks of adult plumage.

Species: Song Sparrow
Most recent capture date: 6/19/2021
Age: less than 3 months old

Species: Northern Rough-winged Swallow
Most recent capture date: 6/19/2021
Sex: Female
Age: at least 1 year old

Notes: Another swallow! Something about the weather and air currents must have encouraged them to fly lower on this day. This species is named for tiny hooks on the outer edge of its outer primary (wing) feather. Its name in Spanish translates to “Serrated Swallow”; in French, “Swallow with Spiky Wings”.

Species: Tree Swallow
Most recent capture date: 6/19/2021
Sex: Male
Age: at least 1 year old

Notes: Swallows forage and breed at CCFS, but they almost never come down low enough to be captured by our nets. We were very excited to get to see this shiny fellow.

Species: Spotted Towhee
Most recent capture date: 6/10/2021
Age: less than two months old

Notes: Spotted Towhee juveniles look nothing like their orange-and-black, red-eyed parents.

Species: Wilson’s Warbler
Most recent capture date: 6/10/2021
Age: less than two months old

Notes: This fellow looks a bit bedraggled due both to having fluffy juvenile plumage and to being in the process of molting into nicer plumage. You can see the juvenile pale brown feathers at the back of his crown, and the new black feathers growing in at the front of the crown.

Species: Wrentit
Most recent capture date: 6/10/2021
Age: less than two months old

Notes: Wrentits have multi-colored eyes: a dark ring around the pupil, then a light ring, then an outer dark ring. The inner and outer dark rings change color with age, being brown in young birds like this one, and deep maroon in older birds.

Species: Common Yellowthroat
Most recent capture date: 5/26/2021
Age: less than two months old

Notes: You can see the yellow “gape” at the base of the bill on this very young warbler. Brightly-colored gapes help baby birds beg for food, exaggerating their open-mouthed begging movements, but the gapes quickly disappear as they grow up. If you see yellow gape, you know you are looking at a brand new bird.

Species: Bullock’s Oriole
Most recent capture date: 6/6/2021
Sex: Female
Age: at least 2 years old

Species: Brown-headed Cowbird
Most recent capture date: 5/2/2021
Age: at least 1 year old
Sex: Female
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Notes: This bird showed signs of having laid eggs recently, which is not surprising if you know the cowbird’s lifestyle: these birds are “brood parasites,” laying eggs in other birds’ nests for those birds to raise alongside their own chicks. Brown-headed Cowbirds are incapable of raising their own chicks, and never build a nest of their own. The females work hard at reproduction in their own way, though: they find and watch the nests of other birds to know when to add their own eggs; they lay extremely quickly, taking less than one minute to lay an egg; and they can lay more than 30 eggs in a season.