Field Trip: American Canyon Wetlands

Date: Friday March 09, 2012

Time: 8:00 AM

Trip report added on 3/13/2012. (NSAS Event)


Trip Report by the leader, Murray Berner
From September-May, it can be easy to find 80-plus species of birds along the eight-mile network of river and marsh trails now open at American Canyon. In general, the best time to visit is from 90 minutes before low tide until an hour before high tide. It is then that the Green Island lagoon attracts several thousand ducks and small waders. On the March 9th field trip, Green-winged Teal was the most abundant duck there, and we had both a hybrid Am X Eur Wigeon and a pure male Eurasian. By mass, American Avocet was the common shorebird, but Least Sandpiper outnumbered the avocet three to one. Rafts of scaup dominated the Napa River, and the twin freshwater polishing ponds north of the landfill had Green Heron and Common Gallinule. Terrestrial favorites were a male Allen's Hummingbird and a "Gray-sided'' Chestnut-backed Chickadee. We walked only 2.5 miles of the birdiest trails, skipping the landfill trail where both Short-eared and Burrowing Owl have been seen this winter.

eBird List:
82 species (+5 other taxa)

Canada Goose (Branta canadensis) 3
Mute Swan (Cygnus olor) 2
Gadwall (Anas strepera) 200
Eurasian Wigeon (Anas penelope) 1 at se corner of Green I. lagoon. Hybrid male nearby: Grey sides, pink breast, dull grey and white face/head, except for copper-colored nape and side of nape
American Wigeon (Anas americana) 130
Mallard (Anas platyrhynchos) 30
Cinnamon Teal (Anas cyanoptera) 8
Northern Shoveler (Anas clypeata) X
Northern Pintail (Anas acuta) 20
Green-winged Teal (American) (Anas crecca carolinensis) 300
Canvasback (Aythya valisineria) 60
Greater Scaup (Aythya marila) 50
Lesser Scaup (Aythya affinis) 15
Greater/Lesser Scaup (Aythya marila/affinis) 150
Aythya sp. (Aythya sp.) 100 99% of divers on Napa R.
Bufflehead (Bucephala albeola) 5
Common Goldeneye (Bucephala clangula) 4
Ruddy Duck (Oxyura jamaicensis) X
California Quail (Callipepla californica) X
Pied-billed Grebe (Podilymbus podiceps) 10
Western Grebe (Aechmophorus occidentalis) 2
Clark's Grebe (Aechmophorus clarkii) 10
Western/Clark's Grebe (Aechmophorus occidentalis/clarkii) 20
Double-crested Cormorant (Phalacrocorax auritus) 4
American White Pelican (Pelecanus erythrorhynchos) 1
Great Blue Heron (Ardea herodias) 1
Great Egret (Ardea alba) 1
Snowy Egret (Egretta thula) 2
Green Heron (Butorides virescens) 3 at poishing ponds
Turkey Vulture (Cathartes aura) 1
White-tailed Kite (Elanus leucurus) 1
Northern Harrier (Circus cyaneus) 2
Red-shouldered Hawk (California) (Buteo lineatus elegans) 1
Red-tailed Hawk (Western) (Buteo jamaicensis calurus) 2
Virginia Rail (Rallus limicola) 1
Sora (Porzana carolina) 1
Common Gallinule (Gallinula galeata) 2
American Coot (Fulica americana) 600
Black-bellied Plover (Pluvialis squatarola) 15
Killdeer (Charadrius vociferus) 10
Black-necked Stilt (Black-necked) (Himantopus mexicanus mexicanus) 11
American Avocet (Recurvirostra americana) 800 ~ half with colored heads. A very rough estimate of total
Willet (Tringa semipalmata) X
Long-billed Curlew (Numenius americanus) 1
Marbled Godwit (Limosa fedoa) 40
Western Sandpiper (Calidris mauri) X
Least Sandpiper (Calidris minutilla) X
Dunlin (Calidris alpina) X
peep sp. (Calidris sp.) X perhaps 2000 total peeps. 90% WESA, 8% DUNL, 2% LESA but numbers too wild to estimate
Long-billed Dowitcher (Limnodromus scolopaceus) 20
Ring-billed Gull (Larus delawarensis) 10
Western Gull (Larus occidentalis) 30
Western x Glaucous-winged Gull (hybrid) (Larus occidentalis x glaucescens) 5
Herring Gull (Larus argentatus) 1
Glaucous-winged Gull (Larus glaucescens) 45
Forster's Tern (Sterna forsteri) 7
Mourning Dove (Zenaida macroura) 8
Anna's Hummingbird (Calypte anna) 5
Allen's Hummingbird (Selasphorus sasin) 1
Nuttall's Woodpecker (Picoides nuttallii) 1
Downy Woodpecker (Picoides pubescens) 1
Northern Flicker (Red-shafted) (Colaptes auratus [cafer Group]) 1
Black Phoebe (Sayornis nigricans) 2
American Crow (Corvus brachyrhynchos) 3
Common Raven (Corvus corax) 2
Tree Swallow (Tachycineta bicolor) 40
Chestnut-backed Chickadee (Poecile rufescens) 2 possible 'grey-sided' bird near end/Eucalyptus Dr. Tiny patch of colore at extreme lower flank. How such a bird got here is puzzling.
House Wren (Troglodytes aedon) 1
Marsh Wren (Coastal Pacific) (Cistothorus palustris [paludicola Group]) 4
Ruby-crowned Kinglet (Regulus calendula) 5
Western Bluebird (Sialia mexicana) 2
Northern Mockingbird (Mimus polyglottos) 1
European Starling (Sturnus vulgaris) 5
American Pipit (Anthus rubescens) 3
Common Yellowthroat (Geothlypis trichas) 4
Yellow-rumped Warbler (Setophaga coronata) 20
Yellow-rumped Warbler (Myrtle) (Setophaga coronata coronata) 1
Yellow-rumped Warbler (Audubon's) (Setophaga coronata auduboni) 10
Song Sparrow (Melospiza melodia) 15
Lincoln's Sparrow (Melospiza lincolnii) 1
White-crowned Sparrow (Zonotrichia leucophrys) 15
Golden-crowned Sparrow (Zonotrichia atricapilla) 10
Dark-eyed Junco (Oregon) (Junco hyemalis [oreganus Group]) 2
Red-winged Blackbird (Agelaius phoeniceus) X
House Finch (Carpodacus mexicanus) X
Lesser Goldfinch (Spinus psaltria) 6
American Goldfinch (Spinus tristis) 2

This report was generated automatically by eBird v2 (

Pre-Trip Description:

A low tide Friday morning will expose all the mud and rock of the American Canyon Wetlands and Napa River and so will attract terns, shorebirds, falcons and wagtails to those places. Wintering sparrows and early migrants of many kinds will be found along this approximately three mile round trip to the river, along its banks, and back via several of the new trails now open. Napa carpool departs at 8:00 am from east side of Sweeney's in Riverpark shopping center. Riverpark is located off Imola Ave between Jefferson and Coombs. That carpool will arrive at the parking lot at the corner of Eucalyptus and Wetlands Edge in American Canyon by about 8:30.

Read more about these trips on the Friday Bird Walks page.

Dialing in © 2009 Frank Toller Lunch break on Friday Bird Walk © 2010 Dave McMullen NSAS Viewing Station at SF Bay Flyway Festival © 2008 Dave McMullen * Murray at Coast.jpg Δ

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