All Photos posted on this blog unless otherwise noted were taken by me with my Canon Rebel XTI using a 300 mm zoom lens

Monday, June 1, 2009

Birds of the Month for June, Avocets and Stilts

I picked two birds as birds of the month for June, the American Avocet and the Black-necked Stilt.
Walk through the wetlands this time of year and you are very likely to see hear and possibly be dive bombed by Avocets and Stilts who are mostly finished nesting but still watching after their young as the feed in the ponds and playas. These two species are often found together wading and foraging in ponds. These two beautiful waders nest in Utah, The Great Salt Lake Wetlands are the nesting ground for some of the largest breeding populations of Avocets and Stilts in North America. They arrive in Utah usually in March but I have seen Avocets as early as February. They stay until The end of October and head to Mexico for the wither. Avocets have the copper colored head and upturned bill, in fall their head color changes from copper to sliver almost white. Stilts are black and white with a straight bill and bright red legs.

American Avocet
With its elegant profile and striking coloration, the American Avocet is unique among North American birds. In summer it can be found in temporary and unpredictable wetlands across western North America where it swings its long upturned bill through the shallow water to catch small invertebrates.
Adult Description
· Large shorebird. Long legs.
· Long, upturned bill.
· Black-and-white upperparts.
· Rusty or gray neck and head.
Immature Description
Similar to adult, but head colored light buff.
Cool Facts
In response to predators, the American Avocet sometimes issues a series of call notes that gradually changes pitch, simulating the Doppler effect and thus making its approach seem faster than it actually is.
Nesting American Avocets aggressively attack predators, sometimes physically striking Northern Harriers or Common Ravens.
A female American Avocet may lay one to four eggs in the nest of another female, who then incubates the eggs. American Avocets may parasitize other species' nests too; single American Avocet eggs have been found in the nests of Mew Gulls. Other species may also parasitize avocet nests. Avocets have incubated mixed clutches of their own eggs and those of Common Terns or Black-necked Stilts. The avocets reared the stilt hatchlings as if they were their own.
American Avocet chicks leave the nest within 24 hours after hatching. Day-old avocets can walk, swim, and even dive to escape predators.
Shallow fresh and saltwater wetlands.
Aquatic invertebrates.
Nesting Facts
Clutch Size
3–4 eggs
Egg Description
Greenish brown with irregular dark spots. Pointed on one end.
Condition at Hatching
Downy and able to walk.
Nest Description
A scrape in the ground, lined with grass or other vegetation, feathers, pebbles, or other small objects, or completely unlined.
In its pre-copulation display, the male American Avocet preens himself with water, gradually gaining intensity to the point of frenzied splashing just before he mounts the female. After copulating, the pair intertwines their necks and runs forward.In territory establishment and in self-defense, performs elaborate ritualized displays. One notable display involves two pairs, or a pair and a third individual, facing each other in a circle and then stretching their bills toward each other. Upon the approach of a terrestrial predator, may approach the predator with a teetering gait and outstretched wings, as if on a tightrope. Also crouches on the ground as if incubating, only to move and crouch again in a new location.Feeds in shallow water, while wading or swimming. Locates food by sight and snaps it up, or sweeps its long bill through the water, capturing prey by touch.
Black-necked Stilt
Adult Description
· Large shorebird.
· Black face, hind neck, and back.
· White throat and underparts.
· Very long, thin red legs.
· Long, thin, straight black bill.
Immature Description
Similar to adult, but with scalloped pattern on back and a white trailing edge to wing.
Cool Facts
Five species of rather similar-looking stilts are recognized in the genus Himantopus. They have the second-longest legs in proportion to their bodies of any bird, exceeded only by flamingos.
The Hawaiian subspecies of Black-necked Stilt has the black of its neck reaching much farther forward than the mainland forms. Habitat loss and hunting led to the decline in its numbers. It uses primarily the few freshwater wetlands found on the Hawaiian Islands.

Shallow fresh and saltwater wetlands, including salt ponds, rice fields, shallow lagoons, and mangrove swamps.
Aquatic invertebrates, feeds in shallow water, while wading or swimming. Locates food by sight and snaps it up, sometimes sticking head completely underwater, or swipes the head and bill through water.

1 comment:

dave and catie said...

My vote is for the Black-necked Stilt. Both beautiful birds. Did you take these pictures yourself? They look stunning.