San Diego Natural History Museum--Your Nature Connection[San Diego County Bird Atlas Project]

WRENDERINGS
Notable Observations
Summer 1998

March brought to San Diego County's coast a rush of northern seabirds including the Black-legged Kittiwake, Northern Fulmar, Ancient Murrelet, and Rhinoceros Auklet. Thanks to Meryl Faulkner and Project Wildlife for supplying the Museum with some specimens that didn't make it through rehabilitation, documenting this incursion.

After a 2-year hiatus, Western and Clark's Grebes are again nesting at their traditional site, Sweetwater Reservoir. On 8 May in square S13, Pete Famolaro found at least 20 nests, most with eggs, some still under construction, and estimated from the number of birds that the number of nests could be twice this high. He confirmed four nests belonging to the Western, one to Clark's, and estimated that the ratio between the species was about 3 Western to 1 Clark's.

Also at the east end of Sweetwater Reservoir in S13, Pete discovered a second San Diego County colony of the Double-crested Cormorant (the other is in the salt works at the south end of San Diego Bay). Occupying a single tree in 1995 and 1996, the colony has now spread to nine trees, with 28 active nests on 8 May.

Suzanne Bond informs us that three pairs of Little Blue Herons are nesting this year on the grounds of Sea World (R8), up from two last year, among 19 pairs of Snowy Egrets.

Ospreys continue to make slow progress in their recolonization of San Diego County. Robert Patton found a pair building a nest on floodlights near Pepper Park in National City (T10), but the birds later abandoned it. Grady Perkins has been monitoring the pair on North Island Naval Air Station (S8), which reused its nest on the floodlights for a ball field. The first clutch apparently suffered predation; a gardener found an eggshell with a hole punched in one end below the nest. But the birds are making a second attempt. Paul and Barbara Zepf followed up a report in a community newspaper of a pair of "goshawks" nesting on the floodlights for the ball field at Scripps Ranch High School (N10)—not surprisingly, they turned out to be another pair of Ospreys. But this nest too was abandoned, and the latest news from David Bainbridge is that the pair is now beginning another nest on a cell-phone tower next to basketball courts on the campus of USIU (O10).

Remarkably late sightings of an immature Bald Eagle were made by Barbara Moore near the Chula Vista Nature Center on San Diego Bay (U10).

Also exceptionally late was Claude Edwards' sighting of a Merlin at San Elijo Lagoon (L7) on 26 April.

A few Swainson's Hawks are regularly seen in spring migration in the Anza-Borrego Desert, and observations at Butterfield Ranch (M23) by Charity Hagen and in the Borrego Valley (F25) by Paul Jorgensen fit this pattern. But they are far rarer nearer the coast, making Nicole Perretta's sighting in Santee (P12) especially notable.

The Ring-necked Pheasant is now rarely seen in San Diego County. This winter's only report was by Debi and Dan Bylin just north of Escondido (H10). Two months later George Salter brought to the Museum a male and a female struck by cars in the same area—possibly another step toward this introduced species' dying out of our area.

The most amazing bird seen this spring was the Sandhill Crane at San Elijo Lagoon (L7) found by Mona Baumgartel on 26 April. Even though a flock winters annually in the Imperial Valley, the species hardly ever occurs as a vagrant away from its normal migration route. In 1919, Frank Stephens wrote that flocks of Sandhill Cranes could be seen "passing high overhead" to and from their wintering grounds at the head of the Gulf of California. But since then the only definite report from San Diego County has been of seven at Cuyamaca Lake in September 1977!

The Virginia Rail is one of the more difficult species to confirm breeding, so Ginger Rebstock's observation of a pair copulating, then feeding two downy black chicks at San Elijo Lagoon was a good one.

Nola Lamken managed to see a Killdeer actually lay an egg in the Barona Indian Reservation, (N14). A behavior not anticipated by the codes on the daily field form! Another sensationally rare find was Elizabeth Copper's discovery of a Wilson's Plover among the Snowies on Delta Beach on the Silver Strand on 27 April. This makes only the fourth San Diego County record of this vagrant from Baja California—the previous ones were in 1991, 1918, and 1894!

The Lesser Yellowlegs is most frequent in fall, generally rare in spring. Robbie Fein and Andy Lazere's eight on 12 April in F5, in the Santa Margarita River valley in Camp Pendleton, were an exceptional concentration.

Roadrunners typically nest in—big surprise—thorny shrubs. But Pat Walsh saw one in the Eastlake area of Chula Vista (T13) coping with urban sprawl invading its habitat by nesting in a pine tree.

Confirmations of breeding can come to us from unexpected sources. In the yard of a resident of Campo (U23), a tree with a nest of Western Screech Owls blew down. The homeowner brought the chicks to the Cleveland National Forest office in Alpine. Forest biologist and atlas participant Kirsten Winter passed the chicks onto the Fund for Animals for rehabilitation and the data onto us.

How do you see Burrowing Owl eggs in their nest? Mike Fugagli, as part of his work for Ogden monitoring road construction, ran a plumber's scope down a burrow and photographed the eggs! Unfortunately, this construction project near the Otay Mesa border crossing (V13) entails the owls' being excluded from their burrows—and ultimately from one of their few remaining sites in San Diego County.

Bill Haas' continuing quest for the Long-eared Owl has disclosed that mysterious species in 15 squares, most recently in Lawson Valley (R17). Extensive undisturbed oak woodland is the key habitat for the Long-eared Owl, revealed by Bill's searches to be far more widespread in San Diego County than anyone guessed before this project began. Phil Nelson saw the species at Tamarisk Grove (I24) on 17 and 18 March but since then they have deserted this traditional site.

Brian Bothner had the Lesser Nighthawk at a site exceptionally near the coast and city: Indian Head Canyon in Leucadia (K7).

Belted Kingfisher nests are a rare find in San Diego County. Margaret and Bert McIntosh had one in an artificial bank near Lake Ramona (M12), but the attempt was abandoned before any young fledged.

This winter's only report of the Yellow-bellied Sapsucker, the eastern representative of the Red-naped and Red-breasted, was by Don Adams from his yard in Tierrasanta (P10).

The Purple Martin has become so rare that any nesting pair is noteworthy. Phoenix von Hendy and Kirsten Winter found one at the Pine Hills Fire Station (L19) on 19 April, and John, Beverly, and Lori Hargrove found another near Magee Road north of Pala (C11).

The Gray Vireo, one of San Diego County's most obscure breeding species, has been reported from two new sites this spring. Dave and Cyndee Batzler found one on the east slope of the Laguna Mountains in Oriflamme Canyon (L22). Kirsten Winter had another in chaparral just northwest of El Capitan Dam (O16), 15 miles west of the closest previously known site on upper Pine Valley Creek, suggesting the species may be substantially more widespread in foothill chaparral than now imagined. When in dry chaparral, listen for a deliberately phrased song like a Black-headed Grosbeak run at half or third speed. But beware the very similar song of Cassin's (Solitary) Vireo.

The Lark Bunting is always a surprise in San Diego County, especially in spring. In the far Anza-Borrego Desert, Charity Hagen had one near Seventeen Palms Spring (F29), and Ginger Rebstock and Karin Forney had a flock of 8 just to the south near Five Palms Spring (G29). Even less expected was one on the coastal side, in Proctor Valley (T14) by Phil Unitt.

A few Green-tailed Towhees were seen during their spring migration in the Anza-Borrego Desert, but only one was reported from near the coast—when it entered one of Jeff Wells and Jennifer Turnbull's cowbird traps in the Tijuana River Valley (W10) on 4 April. Banded and released, it came back for seconds on 8 April! The American Redstart wintering at Guajome Lake stayed at least until 4 April when reported by C. C. Gorman.

The Bronzed Cowbird is gradually becoming more frequent in San Diego County—or is detected more frequently because of widespread cowbird trapping. Paul Jorgensen reports one caught then released from a cowbird trap in the Borrego Valley (G25) on 4 May.

--Philip Unitt

birdatlas@sdnhm.org

Summer 1998 Wrenderings | Wrenderings Archive | Bird Atlas Introduction