Offshore birds made the biggest splash in May. Cruise ships again accounted for the majority of the offshore sightings, but research and container ship reports provided interesting records as well. Three cruise ships sailing through the county waters in early May reported Black-footed Albatross, Pink-footed and Sooty Shearwaters, Pomarine Jaeger, Red Phalarope, and Cassin’s Auklet (many observers=mob). On May 6, an offshore research vessel recorded Cook’s Petrel and a Flesh-footed Shearwater (fide P.Lehman). The most unusual bird though was a Hawfinch (http://goo.gl/1gTlL3) that passed through county waters on 17 May (P.Leahy). This bird was first noticed on a container ship in the western Aleutians and continued with the ship (eating seed provided by the observer) through at least Santa Barbara County waters and likely to the destination port in Los Angeles County. While the method of arrival makes listers uncomfortable, this report clearly shows the potential for ship assisted birds turning up along the coast.
May "bird of the month" honors go to a Magnificent Frigatebird seen over Morro Bay from the north end of Pecho Road on 16 May (J.Royer). This is the first county record since 1998 and also the earliest with previous records spanning from late Jun to mid-Sep. Plumage details indicate this was a female and eliminated both Greater and Lesser Frigatebirds, both of which are both possible in California. There were several other interesting birds at Morro Bay. Two Black Skimmers were there 28-30 May (D.Camilleri, T.Edell). Lingering waterfowl included a Greater White-fronted Goose seen flying over Sweet Springs Nature Preserve on 29 May (J.Carroll), a male Blue-winged Teal in Baywood Cove on 17 May (T.Edell), and a female Greater Scaup still present on 28 May (J.Royer, J.Carroll). Although Bald Eagles are now widespread in the county, two adults perched high in the Morro Bay State Park heron rookery on 17 and 26 May (T.Edell) are the first potential pair present at the bay during the breeding season. The latest dowitcher reports were a Short-billed Dowitcher around the north end of Pecho Road on 28 May (J.Royer) and two Long-billed Dowitchers on 12 May (T.Edell). The number of American White Pelicans shot up from the 7 earlier in the month to 26 on 31 May (T.Edell); May and June increases presumably are the product of failed nesting or sub-adult birds, though where they come from is unknown. A Black-and-white Warbler was seen from the Morro Bay State Park marina boardwalk on 30 May (S.Griffin).
Due to the regular coverage Oso Flaco Lake receives, a female Hooded Merganser there on 30 May (J.Aasen) was new and presumed to be a very late transient. One species drawing a lot of attention there was the pair of Least Bitterns present all month and with two offspring first reported on 12 May (mob). This is a "species of Special Concern" in California and a protected migratory bird and as such visitors should respect its protected status and patiently wait for views rather than playing calls and hoping for a response. State Parks is concerned with the attention this species is receiving and the potential for adverse effects on nesting. Other birds of interest at the lake were a male Hermit/Townsend’s Warbler hybrid (https://goo.gl/OVtGZE) there on 8 May (T.Edell) and a late Hermit Warbler on 22 May (S&L.Terrill). A high count of 10 Yellow-headed Blackbirds was seen on 8 May (T.Edell,M.Smith). Though not seen at the lake, the first Least Tern of the season was noted in the area on 1 May (J.Iwanicha).
A Yellow-breasted Chat continued along the Cottontail Creek drainage at Whale Rock Reservoir through 23 May (T.Edell). This somewhat coastal location is not in the species known nesting range. On the reservoir, a lingering male Greater Scaup on 23 May (T.Edell) may summer there based on past scaup that remained to this date. A female Common Merganser was a bit unusual for this location on 23 May (T.Edell) and a Common Raven heard here on that date (T.Edell) may be resident in the area.
Nearby at Estero Bluffs State Park, a late Ruddy Turnstone was observed on 31 May (D.Keeling) and several Royal Terns lingered into late May with three still present on 22 May (M.Smith). Just south of the park at the Lucerne Drive vista point a White-winged Dove flew north toward the park on 29 May (T.Edell). To the south in Montana de Oro State Park, a Willow Flycatcher at the Islay Creek Campground on 11 May (J.Royer) was the first of five reported during the month. Also found in the campground that day was a male Black-and-white Warbler (J.Royer) that was photographed on 14 May (R.Zachary). A Black-throated Gray Warbler there 11-12 May (J.Royer) provided this year’s the latest spring report.
Birds of interest in the north county were a male Rose-breasted Grosbeak in east Templeton on 6 May (J.Rayner), an adult Chipping Sparrow at Santa Margarita Lake on 1 May (R&R.Zachary), and an American Bittern along Cholame Creek on 12 May (J.Moonjian). Surprisingly, the only Heermann’s Gull reported was one at the Pismo Creek lagoon on 30 May (R.Saval). Other coastal sightings included a late female Common Goldeneye at San Luis Obispo Creek on 12 May (H.Elliott) and a male and female Black-necked Stilt at the mouth of Santa Rosa Creek in Cambria on 5 May (K.Perry). A Common Raven continued along western Turri Road through 30 May (S.Griffin) and 16 Yellow-headed Blackbirds were along the eastern section on 10-11 May (P.Clayton). Three late transients worth noting were a White-throated Sparrow in Nipomo on 5 May (S.Girard), a Red-breasted Nuthatch at Meadow Park in San Luis Obispo on 10 May (T.Edell), and a Audubon’s Yellow-rumped Warbler in Morro Bay on 12 May (K.Perry).
For seasonal status and distribution information about birds mentioned in this report, consult the Morro Coast Audubon publication "The Birds of San Luis Obispo County, California" (available to purchase for $3.00 at MCAS office in Morro Bay), eBird at the following link http://goo.gl/vCBGfy, or contact me at firstname.lastname@example.org. Tom Edell