Monday, June 24, 2013

Eureka! Birds of San Luis Obispo County - May 2013

Gull-billed Tern was added to the county list on 7 May when an adult in breeding plumage was found along the shoreline of the Oceano Dunes State Vehicle Recreation Area by State Park employee Mae Cowgill. A lucky few got to see it that afternoon, as it was gone the next day. Recent surveys at the South San Diego Bay National Wildlife Refuge salt ponds breeding colony don’t bode well for another visit in the immediate future. According to Robert Patton, from 20 April to 15 May 2013, at least 65 pairs were present. However from 12 to 25 May, carcasses of 90 adults were observed at the salt works and other locations in the area. About 7 percent of the subspecies’ population and 62 percent of the state population was lost. Testing is underway to determine the cause of mortality. There is still hope for the colony because it consisted of only 11-20 pairs in 1999.

According to eBird 213 species were recorded in SLO County in May and a total of 296 species have been recorded in 2013. Abbreviations: OFL = Oso Flaco Lake; PSBOC = Pismo State Beach Oceano Campground; WRR = Whale Rock Reservoir.

WATERFOWL THRU ALBATROSS: The SNOW GOOSE continued through the month at PSBOC (mob) while the ROSS’S GOOSE with it all winter was last recorded on 1 May (MLS). A male and female NORTHERN SHOVELER at a residential pond along Hwy 58 on the Carrizo Plain on 31 May (TME) were either late transients or breeding locally; there is only one breeding record for the county. A male HARLEQUIN DUCK seen off the north end of Cayucos on 15 May (JI) suggests one may again summer at Estero Bluffs State Park. A late male BLACK SCOTER was seen from Margo Dodd Park in Shell Beach on 6 May (PK). Two COMMON MERGANSERS along the Salinas River in Atascadero on 31 May (RHZ) suggest nesting nearby. A repositioning cruise passing about 50 miles off SLO County on 8 May recorded three LAYSAN ALBATROSS, 68 BLACK-FOOTED ALBATROSS and one PELAGIC CORMORANT that at 48 miles southwest of Point Piedras Blancas was unusually far offshore (PEL).

HERON THRU MURRELET: Due to little suitable habitat, there are only a few GREEN HERON records from the Carrizo Plain with most in spring; a transient was at residential pond along Hwy 58 on 14 May (TME). Of the 12 WHITE-FACED IBIS passing through the county from 3-15 May, the most unusual was one on the lawn at the Pacheco School in San Luis Obispo on 5 May (DW). SWAINSON’S HAWK pairs were again in the Cuyama Valley and near Shandon all month; however a light-morph adult that fl ew past WRR on 10 May (SF) was a fi rst for that location. A COMMON GALLINULE (previously Common Moorhen) at OFL 23-31 May (KJZ) was the fi rst to be reported in the county this year. Up to six BLACK-NECKED STILTS were at Whale Rock Reservoir on 2 May (KLP) and another was at Oso Flaco Lake on 31 May (DML). A SOLITARY SANDPIPER was at WRR 1-3 May and a late RUDDY TURNSTONE was at Cayucos on 29 May (KLP). While looking for the Gull-billed Tern, a late fi rst-spring MEW GULL was found along the beach at the Oceano Dunes State Vehicle Recreation Area (RN). Three migrant BLACK SKIMMERS were seen from Sweet Springs Nature Preserve on 5 May (TM) and another was at Pismo Beach on 6 May (MB) where it was seen south of the pier and foraging over the ocean off Margo Dodd Park (PK). Two SCRIPPS’S MURRELETS seen west of SLO from the repositioning cruise were about 60 miles southwest of Point Buchon on 8 May (PEL).

NIGHTHAWK THRU SPARROW: Although expected in the eastern part of the county Apr-Jul, nine LESSER NIGHTHAWKS on the Carrizo Plain National Monument at Quail Springs on 30 May (TME) was a high count for the county. Migrant BLACK SWIFTS passed through our area in May with at least 18 at OFL from 4-27 May that included a high count of 15 on 24 May (TME,MLS). Of the 18 WILLOW FLYCATCHERS reported from 14-31 May, only one was in the western part of the county at Cerro Alto Campground on 14 May (MLS). The county’s fi rst spring and only 16th EASTERN KINGBIRD record was seen on a ranch east of Cayucos on 4 May (GPS). Single BANK SWALLOWS were at OFL on 8 May (RN), 10 May (TME) and 25 May (MLS); this is the best place in the county to fi nd this species during spring migration. A VARIED THRUSH at Cerro Alto Campground on 3 May (JSR) provided the second latest spring record for the county. A BLACK-THROATED SPARROW at Quail Springs in southeastern SLO County 26-28 May (PAG) was in an area this species is suspected to breed, but has yet to be confi rmed. The latest WHITE-THROATED SPARROWS were at Cerro Alto on 2 May (MLS) and at Camp Keep in Montana de Oro State Park on 3 May (SCS).

TANAGER THRU ORIOLE: An adult male SUMMER TANAGER found at a ranch east of Cayucos on 4 May (TM) is presumed to be an early spring migrant. WESTERN TANAGER is a rare breeder in SLO County that seems to occur with some regularity in summer at Cerro Alto; a pair was observed copulating in the campground on 29 May (MLS). An adult ROSE-BREASTED GROSBEAK was at the PSBOC 18-20 May (TS).Two unusually large fl ocks of TRICOLORED BLACKBIRDS along the north coast may pertain to the same birds with 700 along Santa Rosa Creek Road on 10 May (SF) and 1,200 along Hwy 1 near Hwy 46 on 20 May (TME). Fourteen YELLOW- HEADED BLACKBIRDS were reported from 3-15 May with a high count of 12 at OFL on 3 May (MLS). Following on last month’s SCOTT’S ORIOLE reports from Quail Springs, two males on 26 May included one at Quail Springs and another a little north of there (PAG,WK).

OBSERVERS: Thanks to everyone who report their sightings, primarily via the yahoo “slocobirding” listserv and eBird, including those cited above: Mick Bondello, Tom M. Edell, Sam Fitton, Peter A. Gaede, Jessica Griffi ths, Jodi Isaacs, Peter Kaestner, Will Knowlton, Paul E. Lehman, Dave M. Lawrence, Tom Maloney, Richard Norton, Kaaren L. Perry, Jim S. Royer, Brad K. Schram, Steve C. Schubert, Tom Slater, Gregory P. Smith, Maggie L. Smith, Dave Wilson, 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