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Exploring the beautiful nature of California
California Nature: Shorebirds
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Most Shorebirds walk along shores probing
for food with their thin sensitive bills. Bill length varies
considerably so differing species can work the same shore and
obtain different food supplies. Shorebirds include sandpipers,
godwits, stilts, oystercatchers, plovers, and many more. The
majority of species eat small invertebrates picked out of the
mud or soil. There are 86 species world wide, 65 North American
species, and 47 Californian species.
Laridae is a family of medium to large birds seabirds and
includes jaegers, skuas, gulls, terns, kittiwakes and skimmers.
They are typically grey or white, often with black markings on
the head or wings. They have stout, longish bills and webbed
feet. There are 108 species world wide, 54 North American
species, and 44 Californian species.
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Like all North American terns, the least tern
has long, pointed wings and a deeply forked
tail. It is the smallest of our terns, and bears
outer wing feathers that edge the light-gray
wings in black. The breeding adult is gray
above, white below, with a black cap. In early
spring least terns return from wintering grounds
in Latin America.
They soon pair up using courtship rituals in
which hopeful males offer small fish to
prospective mates. The shorebirds nest in very
shallow depressions on broad expanses of bare
sand, which camouflage the eggs. They lay from
mid-April in south Florida to the first of May
in the north, and the eggs hatch after 21 days.
The young leave the nest in a few days, but
don't begin to fly safely until about three
weeks later. Populations of least terns sank
after the turn of the century, when they were
hunted to harvest their feathers to decorate
women's hats.
Not only are the birds extremely susceptible to
nest disturbance, they have lost extensive
nesting habitat to beach development and
increased human activity there. Least terns are
colony nesters, meaning they nest in a group,
which allows them to exchange information about
food sources, as well as to detect and mob
predators. An entire colony can be easily
destroyed by predation by red foxes, raccoons,
dogs and house cats, by human trampling, or by
catastrophic storms. |
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Snowy Plover can be found along the west coast from Washington
to Baja California and along the Gulf Coast from Florida to the
Yucatan Peninsula. Preferred habitats include sandy coastal
beaches and shallow alkaline lakes. The snowy plover is a small
bird with pale brown upper parts and white under parts. This
bird has dark patches on either side of upper breast, behind
eye, and on it's white forehead. The snowy plover's bill, legs,
and feet are black.
The Spotted Sandpiper is the most widespread-breeding sandpiper
in North America. Spotted sandpipers feed on a great variety of
animal matter and they occupy almost all habitats near water,
everything from the shorelines of wild rivers and lakes to urban
and agricultural ponds and pools. Easily identified in breeding
plumage by the presence of dense ventral spots, the Spotted
Sandpiper is also known as a little shorebird teetering along
the water’s edge. Spotted
Sandpipers (along with several other species of
scolopacids) are among a small minority of
birds that have
reversed sex roles; i.e., females are more aggressive and active
in courtship than males, and males take the primary parental
role.
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The Northern Jacana as with most Jacanas is easily
identified by its long toes. Their bodies are about the same
size as a robin. The body is mostly dark with black plumage on
the head and neck. The Northern Jacana has pale green flight
feathers and a distinctive yellow bill and
frontal shield. Juveniles have white underparts. These
unusual birds are also identified by their harsh “jik” call
which progressively speeds up to a chatter. The large feet and
claws of the Northern Jacana are what give it the ability to
walk atop floating vegetation. In fact, the toes cover an area
of 12 by 14 cm, thus dispersing the bird’s mass over a large
area. They are particularly fond of lake and fresh-water marsh
habitats.
Northern Jacanas are known for being quite aggressive and territorial. They
frequently fight with each other using their weapons – spurs located on the bend
of the wing. Floating nests are built on the water. Female Northern Jacanas are
polyandrous and are often spoken of as the prostitute bird. A clutch of 3 to 5
eggs is laid in the floating nest which is built and cared for by the male. The
male
Northern Jacana incubates the eggs for a period of 22 to 24 days whilst the
female guards her males. Once the young ones hatch, they will fledge in 28 days.
The father will teach his precocial chicks how to forage for various foods such
as insects, mollusks, worms and fish. Should danger approach, he will carry them
under his wings. Its quite easy to understand why the unique Northern Jacana’s
are popular amongst
bird watchers. |
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Since it is one of the largest and heaviest
of our shorebirds, the oystercatcher is unmistakable. It is
striking in appearance: dark-brown, black, and white, with a
bright red bill. When in flight, a diagonal white stripe in each
wing forms a V-pattern.
Oystercatchers get their name from their habit of snatching
oysters from slightly open shells. They also use their powerful
bills to open mollusks and to sort through heavy shells in
search of food.
The oystercatcher needs extensive sandbars and mudflats for
feeding and sand or shell-covered beaches free from predators
and human disturbance for nesting. The birds usually nest in
shallow depressions scraped out of sand, in areas surrounded by
water, since they are very sensitive to disturbance and
susceptible to mammalian predators. Unfortunately the
availability of safe nesting places is declining
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| Blackbirds
California Condor
Cardinals
Cranes
Crows, Jays,
& Magpies Eagles
Finches
Flycatchers
Hawks
Hummingbirds
Owls Game Birds
Raptors
Shore Birds
Sparrows
Tanager
Thrushes
Vultures
Wading Birds Warblers
Woodpeckers
Wrens |
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