By Jim Acquire
Be taught 100 Widespread Valley Birds is a photograph weblog sequence highlighting 100 of the commonest Valley chicken species.
Submit #12 within the Be taught 100 Widespread Valley Birds sequence. (Species 16 and 17/100.)
In Half I of the Our Wintering “White” Geese submit, we realized in regards to the bigger “white Goose with the Grinning Patch”, the Snow Goose.
On this submit the star of the present is the extra diminutive Ross’s Goose.
ROSS’S GOOSE Anser rossii (Cassin, 1861)
The Ross’s Goose is a Pretty Widespread Winter Customer discovered nearly completely in winter within the Central Valley. Just like the Snow Goose, its referred habitats are recent emergent wetlands, adjoining lacustrine waters, and close by moist croplands, pastures, meadows, and grasslands. Pretty Widespread from November to early March.
Plumage is just like white morph of Better and Lesser Snow geese, however common annual physique mass of Ross’s Goose is 60% and 67% of those species. Feathers of lore meet base of maxilla forming a straight line as an alternative of a ahead curved arc typical of Better and Lesser Snow geese.
On basal half and sides of maxilla, notably in mature males, are species-specific vascular wartlike protuberances or caruncles which change into extra prevalent with age and probably act as a badge or standing image, serving to restrict contests amongst conspecifics.
Just like the “Blue morph” Snow Goose, the grownup blue morph Ross’s Goose has the identical darkish gray-brown physique however a decreased quantity of white confined to simply the pinnacle.
The chances of discovering a darkish or “Blue” morph have been calculated at about 0.008% (3 out of 38,825).
The primary wintering space for the species is presently the Central Valley of California. The entire variety of birds has elevated from a recorded low of two,000–3,000 within the early Nineteen Fifties to greater than exceed 2 million birds in 2009.
The feminine Ross’s Goose does all the incubation of the eggs. The male stays close by and guards her the entire time. The feminine covers the eggs with down when she leaves the nest. The down retains the eggs heat whereas she is away and should assist cover them from predators.
Earlier posts from the Be taught 100 Widespread Valley Birds sequence,