Wednesday, August 21, 2013

Eureka! Birds of San Luis Obispo County - June/July 2013

Southern California’s first VAUX’S SWIFT nest was confirmed in Atascadero this summer thanks to Bill Rucci. On 5 Jul, Bill noticed two swifts flying over his home and called Kevin Zimmer who confirmed they were Vaux’s Swifts. Bill continued to watch for the birds and on 10 Jul noticed they appeared to be entering one of his chimneys. By shining a flashlight down the chimney he spotted a nest clinging to the inside of the (unused) chimney surrounded by feces. Bill told Kevin on 25 Jul that he was “hearing periodic bouts of raspy food begging-type calls coming from the chimney on a daily basis.” Looking down the chimney Kevin spotted a nest with two young and managed photos of an adult in the chimney. This report follows other sightings of Vaux’s and unidentified swifts at Atascadero in summer, the first in 1990. All this suggests that Vaux’s Swift may be a very rare and irregular breeder in the Atascadero area.

According to eBird 196 species were recorded in SLO County in June and July and a total of 301 species have been recorded in 2013. Abbreviations: OFL = Oso Flaco Lake; PSBOC = Pismo State Beach Oceano Campground; WRR = Whale Rock Reservoir.

WATERFOWL: The SNOW GEESE at Oceano County Park and Laguna Lake were both last recorded in early Jul (MLS), but certainly remained through the period. It is not unusual for BRANT to summer in the county; however 72 on the north coast at Arroyo Laguna on 21 Jun (TME) exceeded previous summer counts. One male NORTHERN PINTAIL was at Morro Bay 24 May-1 Jun (TME) and another was at Lopez Lake 16-22 Jun (DML). Also at Lopez Lake, a male GREEN-WINGED TEAL was along the Wittenberg arm 16-22 Jun (DML). Both the male RING-NECKED DUCK and a male GREATER SCAUP continued at WRR thru the period (mob). A female LESSER SCAUP was seen on Morro Bay from White Point on 5 Jul (TME). A male HARLEQUIN DUCK summering at Estero Bluffs State Park 18- 26 Jul (TME) is likely the same bird present there last summer. A transient male BUFFLEHEAD at WRR on 21 Jul (TME) was not seen again at this regularly checked location. A male RED-BREASTED MERGANSER at San Simeon Cove 20 Jun-1 Jul (JG) was either a second year bird or an adult going into eclipse plumage.

GREBE THRU GALLINULE: Up to two EARED GREBES in breeding plumage off Morro Strand State Beach 9-16 Jun (TME) were late while six in breeding plumage off Old Creek in Cayucos on 27 Jul were likely early post breeding dispersants. A calling adult AMERICAN BITTERN at Laguna Lake 1 Jun-17 Jun suggests breeding there, though juveniles have yet to be recorded. A transient WHITE-FACED IBIS at OFL 23 Jun (MLS) provided one of our few mid-summer county records. The county’s two pairs of SWAINSON’S HAWKS, one in the Cuyama Valley and the other near Shandon, were both incubating eggs in Jun and a fl edged young was seen at the Shandon nest on 25 Jul (JM). The COMMON GALLINULE reported last month was last recorded at OFL on 3 Jun (MLS).

SHOREBIRDS: SEMIPALMATED PLOVER is irregularly present in summer on Morro Bay where up to ten were present 9-16 Jun (TME). A WANDERING TATTLER along the coast south of Point Piedras Blancas on 9 Jun (MM), a LEAST SANDPIPER at Morro Bay on 9 Jun, a Long-billed Dowitcher at WRR on 9 Jun (TME), and two unidentifi ed dowitchers at Morro Bay on 16 Jun, were either late northbound transients or summered locally. Although a common species along the immediate coast, a MARBLED GODWIT at Atascadero Lake on 15 Jul (RHZ) apparently represents the fi rst county record east of the Santa Lucia Range. A RUDDY TURNSTONE in breeding plumage at Morro Bay on 23 Jun (TME) was likely an early southbound migrant and as such represents the county’s earliest fall arrival. Six adult BLACK TURNSTONES at Villa Creek Beach on 27 Jun (JC) tied the county’s early arrival date. A molting adult SEMIPALMATED SANDPIPER was found in the eastern most Turri Road tidal pond on 20 Jul (TME). A lone DUNLIN in breeding plumage at Morro Bay on 1 Jun (TME) may have been one of the two there on 23 Jun (TME) that apparently summered on the estuary. WILSON’S PHALAROPE is one of the latest spring and earliest fall shorebirds; hence an adult at WRR on 1 Jun (TME) is likely a late spring migrant and an adult female at the Turri Road tidal ponds on 9 Jun (TME) may have been an early fall (southbound) migrant. Three RED- NECKED PHALAROPES at WRR on 3 Jun (MLS) were late northbound migrants.

GULL THRU CARACARA: A worn second-year MEW GULL along San Luis Obispo Creek in Avila 6-19 Jun (JG) may have been the same bird seen along the Oceano Dunes State Vehicle Recreation Area in May. The fi rst ELEGANT TERN of the season was found at Pismo Creek Mouth on 17 Jun (BKS); this species was not recorded again until 5 Jul. The fi rst sighting of a fall MARBLED MURRELET was at San Simeon Creek mouth on 29 Jul (TME). A new early fall arrival date was set for RUFOUS HUMMINGBIRD on 3 Jul (BKS) when a male visited a feeder in Arroyo Grande. The bird generating the most excitement all month was an adult CRESTED CARACARA seen in two locations in Jun and Jul (3rd county record). It was fi rst found along the northern portion of Estero Bluffs State Park on 29 Jun (DML,mob), vanished the next day, and was discovered again along Los Osos Valley Road near Jacaranda Lane 13-20 Jul (JW,mob) where it played hide and seek with birders for eight days.

FLYCATCHER THRU BLACKBIRD: A WILLOW FLYCATCHER at the Carrisa Plain School on 19 Jun (PAG) extended the county’s latest spring migrant date by four days. Two singing PACIFIC WRENS along Coon Creek in Montana de Oro State Park on 2 Jun (AFS) are part of the county’s only documented annual breeding location and luckily continue following the fi re that burned through the creek last fall. Up to three BLACK-THROATED GRAY WARBLERS at Cerro Alto 28-30 Jul (WK) were the earliest to be found away from a known breeding location, possibly the Coulter pine forest on West Cuesta Ridge. Also present at Cerro Alto on 28 Jul (WK), was the fi rst HERMIT WARBLER ever found in the county in July. Two male ROSE- BREASTED GROSBEAKS were reported, one visiting a feeder in See Canyon 3-11 Jun (SKB) and another at Cerro Alto 28 Jun-5 Jul (JR). An “Oregon” type DARK-EYED JUNCO at a ranch on the southern Carrizo Plain on 9 Jul (KS) provided the fi rst July record for the Carrizo Plain National Monument. A YELLOW-HEADED BLACKBIRD at OFL on 1 Jun (MM) was rather late for a spring migrant.

OBSERVERS: Thanks to everyone that reports their sightings, primarily via the yahoo “slocobirding” listserv and eBird, including those cited above: Sara Knowles Bilsten, Jay Carroll, Tom M. Edell, Peter A. Gaede, John Garrett, Jessica Griffi ths, Will Knowlton, Dave M. Lawrence, Michelle Maani, Jennifer Moonjian, Kaaren L. Perry, Jonathan Rowley, Alan F. Schmierer, Brad K. Schram, Kathy Sharum, Maggie L. Smith, James White, Roger H. Zachary, Kevin J. Zimmer, and many observers (mob). For seasonal status information about birds mentioned in this report, consult the Morro Coast Audubon publication “The Birds of San Luis Obispo County, California” or contact Tom Edell at (805) 995-1691 or Edell