Abbotts Lagoon

Abbotts Lagoon is a two-stage lagoon near the western coast of the Point Reyes National Seashore. The upper lagoon is a fresh water impoundment which overflows into a lower brackish level with occasional winter tidal exchange.^[2] The eastern shore of the lagoon is covered with old growth northern coastal scrub including Coyote Bush, Yellow Bush Lupine, Sword fern and California blackberry.^[3]

Geology

Abbotts Lagoon is usually separated from the Pacific Ocean by dune sand to the west. The eastern side of the lagoon is bordered by Miocene marine sediments to the north and Pliocene marine sediments to the south from sedimentary rock formations on the western side of the San Andreas Fault.^[4] Santa Margarita Sandstone atop the Monterey Formation forms a ridge along the southern side of the valley containing the upper lagoon, and is exposed along the eastern shoreline of the lower lagoon.^[5]

History

Coast Miwok lived in the area prior to 19th century European colonization. Land surrounding the lagoon was used for cattle and dairy ranching by the 1870s.^[5] Abbots Lagoon was variously identified as Abbott's Lagoon Bombing Target, Abbott's Lagoon Target Area, Abbott's Lagoon Bombing Range, and Bombing Range Number Two while used as a dive bomber practice area by pilots from Alameda Naval Air Station and Santa Rosa outlying field from 1941 to 1952.^[6] The lagoon was designated part of Point Reyes National Seashore in 1962.^[5]

Recreation

Walking trails provide access to observe the birds and wild flowers of the locally unique habitats surrounding Abbotts Lagoon.^[7] Brush Rabbits, Black-tailed Jackrabbits, Pocket gophers, Muskrats, and Black-tailed Deer may be seen around the lagoon. Coyote, Bobcat, Gray fox, Long-tailed Weasel, Striped Skunk, Raccoon, Badger, and Cougar are rarely seen.^[8]

Birding

Bird species observed at Abbotts Lagoon include:

• Auks - Common Murre^[9] - Pigeon Guillemot^[9]
• Blackbirds - Brewer's Blackbird^[9][10] - Brown-headed Cowbird^[9] - Red-winged blackbird^[7][9][10] - Tricolored Blackbird^[9]
• Cormorants - Brandt's Cormorant^[9] - Double-crested Cormorant^[9][11] - Pelagic Cormorant^[9]
• Ducks - American Wigeon^[9] - Bufflehead^[9][12] - Cinnamon Teal^[9] - Common Goldeneye^[9] - Common Merganser^[9] - Gadwall^[9] - Greater Scaup^[9] - Green-winged Teal^[9] - Lesser Scaup^[9] - Mallard^[9] - Northern Pintail^[9] - Northern Shoveler^[9] - Red-breasted Merganser^[9] - Ring-necked Duck^[9][12] - Ruddy Duck^[9][11][13] - Surf Scoter^[9][13]
• Eagles - Golden Eagle^[14]
• Falcons - Merlin^[9] - Peregrine Falcon^[9][14] - Prairie Falcon^[9]
• Finches - American Goldfinch^[9] - House Finch^[9]
• Geese - Black Brant^[15]
• Grebes - Black-necked Grebe^[9][11][13] - Clark's Grebe^[9][11] - Horned Grebe^[9] - Pied-billed Grebe^[9][12] - Western Grebe^[9][11]
• Gulls - California Gull^[9] - Common Gull^[9] - Glaucous-winged Gull^[9] - Heermann's Gull^[9][16] - Herring Gull^[9] - Ring-billed Gull^[9] - Thayer's Gull^[9] - Western Gull^[9]
• Hawks - Cooper's Hawk^[9][12] - Ferruginous Hawk^[9] - Northern Harrier^[9] - Osprey^[9][14] - Red-shouldered Hawk^[9] - Red-tailed Hawk^[9] - Rough-legged Buzzard^[9] - Sharp-shinned Hawk^[9] - White-tailed Kite^[9][12]
• Herons - American Bittern^[9] - Great Blue Heron^[9][11][17] - Great Egret^[9] - Snowy Egret^[9]
• Hummingbirds - Allen's Hummingbird^[9] - Anna's Hummingbird^[9]
• Larks - Shore Lark^[9] - Western Meadowlark^[9]
• Loons - Black-throated Loon^[18] - Great Northern Loon^[9] - Pacific Loon^[9] - Red-throated Loon^[9]
• Owls - Barn Owl^[9] - Burrowing Owl^[9] - Short-eared Owl^[9]
• Pelicans - Brown Pelican^[11][12][13] - Great White Pelican^[9]
• Phoebes - Black Phoebe^[9][12] - Say's Phoebe^[9]
• Pipits - Buff-bellied Pipit^[9][13]
• Plovers - Grey Plover^[11] - Kentish Plover^{[9][12][13][16]} - Killdeer^[10] (The local sub-species of Kentish plover is known as the western snowy plover and is considered "threatened" under the Endangered Species Act.)
• Quail^{[7][9][10][16]}
• Rails - American Coot^[9][12] - Virginia Rail^[9][12]
• Raven^[9]
• Sandpipers - Greater Yellowlegs^[13] - Marbled Godwit^[9][11] - Sanderling^{[9][11][12][13]} - Willet^[9] - Wilson's Snipe^[12]
• Sparrows - Fox Sparrow^[9][13] - Golden-crowned Sparrow^[9] - Grasshopper Sparrow^[9] - Savannah Sparrow^[9][11] - Song Sparrow^[9][10][12] - Spotted Towhee^[9] - White-crowned Sparrow^[9][10][12]
• Swallows - Barn Swallow^[9] - Cliff Swallow^[9] - Northern Rough-winged Swallow^[9] - Tree Swallow^[9] - Violet-green Swallow^[9]
• Swans - Trumpeter Swan^[19] - Tundra Swan^[15]
• Terns - Caspian Tern^[9] - Elegant Tern^[9]
• Thrushes - Western Bluebird^[9]
• Vulture^[9]
• Warblers - Common Yellowthroat^[9][10] - Ruby-crowned Kinglet^[9] - Yellow-rumped Warbler^[9][12][13]
• Woodpeckers - Northern Flicker^[9]
• Wrens - Bewick's Wren^[9] - Marsh Wren^[9]
• Wrentit^[9]

Flora

Abbotts Lagoon is the location of the single remaining natural population of the endangered plant species Sonoma spineflower (Chorizanthe valida).^[20]

References