By Jon Fisher

For The Western Tanager, July/August 2017

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As we head into mid-June, as always it seems spring migration has ended all too soon.  Yet it’s hard to complain about brevity when it spans nearly half the year. 

A good number of rarities appeared this spring, with an increase in late May and June fitting the classic pattern of late season vagrancy in passerines.  As it often is, San Clemente Island was impressive when it came to producing good birds.

The appearance of several southeastern passerines–Yellow-throated Vireo, White-eyed Vireo, Hooded Warbler and Northern Parula–mirrored to a lesser extent the record year of 1992 when well above average numbers of these vagrants reached California.  Yet the reason for their occurrence, both then and now, remains a mystery.

Late April illustrated just how many passerines traverse the area, with a surprisingly large movement of birds noted at Hansen Dam and lesser numbers at other locations contemporaneously.  Significant northerly winds appeared to be largely responsible for the orientation and numbers of these birds, and weather clearly plays a substantial role in migration.  This is especially true on the deserts, but its effect elsewhere sometimes appears inconsistent. 

Following our first wet winter since 2010-2011, some interesting discoveries foreshadowed the potential of the San Gabriel Mountains.  Between the Station Fire in 2008 and subsequent years of drought, birdlife in the mountains has truly been challenged.  Habitat has been radically altered and degraded.  Thankfully both have benefitted greatly from last winter’s rains.    

Birds face a litany of threats.  Fortunately Domoic acid is not often a significant one.  This spring however, this toxin was present in increased levels, primarily due to warmer than normal ocean temperatures and intensified by nutrient rich urban/suburban runoff which spurs the growth of the algae that produces it.  Though the acid doesn’t affect birds directly, it accumulates in the fish on which they feed.  It caused a number of seabird and mammal deaths.  Hundreds of loons, grebes, murres, and others were found deceased or captured and treated, which indicates that thousands of birds that were never found must have been sickened or died.

On a more positive note, our America’s Birdiest County event took place from April 28-30.  This year’s total was 264 species, less than our better years but about in line with the long term average and an impressive variety for three days of coverage.

Waterfowl of note during the period included a lone Brant at Quail Lake on May 7 (Kimball Garrett) and two rather late Greater Scaup at Bonelli Regional Park in San Dimas on May 7 (Tom Benson, Brittany O’Connor), with one still there on May 11.

Inland Red-breasted Mergansers were at Bonelli Regional Park on May 8 (K.D.), at the Piute Ponds on Edwards AFB on May 21 (David Bell) and at the Earvin Magic Johnson Recreation Area in Willowbrook on June 1 (Chris Dean).

White-winged Doves were near Llano in the southern Antelope Valley on April 21 (Ruth Gravance), at Cressa Park in Long Beach on April 24 (Elias Zuniga), at Pt. Fermin Park in San Pedro on June 2 (David Ellsworth) and at Apollo Park near Lancaster on June 3 (Andrew Lee).

A few Inca Doves persist at Col. Leon H. Washington Park in Los Angeles, with at least one reported there through May 19.

Common Ground-Doves continued along the San Gabriel River in the Bellflower/Cerritos area through May 29, with up to three there on April 16 (Becky Turley).  Another was at Peck Road Water Conservation Park in Arcadia on April 25 (Michelle Kwan) and up to three were at the Linden H. Chandler Preserve in Rolling Hills Estates with one present through June 13. 

Three Black Swifts were at the usually reliable spot above Claremont–Cobal Canyon and Claremont Wilderness Park–from May 19–June 13 (Tom Miko).

Way out of season was a Mountain Plover at the Piute Ponds on May 23 (Jon Feenstra).

Remarkably, for the first time in seventy years, Snowy Plovers are breeding on LA County beaches, albeit in very small numbers.  Santa Monica Beach, Dockweiler and Malibu Lagoon all had active nests this spring.  More aggressive protection of potential nesting sites seems to have paid dividends.  With persistence and a bit of luck- on the part of both the birds and humans- this small start could result in the re-establishment of coastal breeding colonies. 

Of note at the Piute Ponds was a late Semipalmated Plover from June 9–10, a Whimbrel on June 13 (both John Birsner) and a Pectoral Sandpiper from June 2–5 (Jon Feenstra).

A rare spring Ruff was discovered on the beach at Pt. Dume in Malibu on May 6 (Devon DeRaad)

An injured Guadalupe Murrelet was by the Cabrillo Beach Fishing Pier on May 26 (David Ellsworth).

Lingering late were two Glaucous-winged Gulls at Lake Balboa in Van Nuys from May 5–June 14 (Mike Stensvold).  An Elegant Tern at the Piute Ponds on May 2 was an unprecedented desert record away from the Salton Sea (Darren Dowell).

Though a few summer along the coast, a Common Loon at Bonelli Regional Park in San Dimas from May 13–19 was late inland (Chuck Burt).

Magnificent Frigatebirds included one off Cabrillo Beach in San Pedro on April 25 (fide Bernardo Alps) and another just outside Long Beach Harbor on May 27 (Alex Cruz Jr.).

A Neotropic Cormorant continued at Bonelli Regional Park in San Dimas through May 18, with two birds confirmed there on May 16 (Rod Higbie, Tom Miko).  Rare inland was a Brown Pelican also at Bonelli from May 31-June 10 (Rod Higbie).

A Yellow-crowned Night-Heron was at El Dorado Park in Long Beach on April 19, with a pair building a nest observed there on April 30 (Cindy Crawford).  Sightings continued through May 30 when one was rescued after becoming entangled in fishing line.  This marks the first known breeding attempt for the county.  Another bird continued in the Ballona Wetlands area through May 19 and an equivocal but likely Yellow-crowned was at Apollo Park near Lancaster during the latter half of May (Steve Bernal).  This species is clearly increasing in the county and additional breeding should be watched for.

Scarce in the county was an American Bittern at the Ballona Freshwater Marsh near Playa Vista on April 15 (Ron Cyger).

Quite late for a spring migrant was a Swainson’s Hawk at Colorado Lagoon in Long Beach on May 27 (Tracy Drake).

A very late spring Lewis’s Woodpecker was at Charlton Flat in the San Gabriel Mountains on June 3 (Larry Schmahl).  This species is typically an irruptive and irregular fall and winter visitor with numbers varying from year to year, but a June record is exceptional. 

The Least Flycatcher at the Rio Hondo Flood Basin continued through April 15.  Coastal slope Vermilion Flycatchers were at Madrona Marsh in Torrance from April 14-15, while elsewhere a few continued at Oakdale Memorial Park in Glendora and at the Castaic Sports Complex.

Plumbeous Vireos found along the Santa Clara River in Valencia on April 21 (Dan Maxwell), in the east Antelope Valley on April 28 (Andrew Lee), at Bixby Marshland on May 6 (Philip Carnehl) and at Guffy Campground near Big Pines on May 21 (Matthew Schmahl) were all presumably spring migrants.

Yellow-throated Vireos, the first of the moderate wave of southeastern vagrants, were at Rocky Oaks Park in Malibu from April 22–23 (Kimball Garrett), at Sycamore Canyon in Whittier on May 16 (Brittany O’Connor) and on San Clemente Island on June 2 (Nicole Desnoyers).

Far rarer but fitting the same pattern was a White-eyed Vireo found along the Playa Vista Riparian Corridor on May 30 and remaining through June 11 (Don Sterba).  This was the first found in the county since 2012.

Purple Martins included three at the Piute Ponds on Edwards AFB on April 25 (Jon Feenstra), five at Hansen Dam from April 27-28 (Kimball Garrett) and two at Peck Road Water Conservation Park in Arcadia on May 29 (Larry Schmahl).

Both late and at an unusual location was a Mountain Bluebird at Guffy Campground near Big Pines on May 21 (Matthew Schmahl).

The returning wintering Gray Catbird at Monte Verde Park in Lakewood was reported through April 23.

Late but not entirely unexpected were single Cedar Waxwings in Pasadena on June 12 (John Garrett) and at the Sepulveda Basin in Van Nuys on June 13 (Daniel Tinoco).

Northern Waterthrushes were at Malibu Creek State park on April 29 (Mark Osokow) and at the Piute Ponds on Edwards AFB on May 16 (Darren Dowell).

A Black-and-white Warbler continued at Madrona Marsh in Torrance through April 19.  Others were at Ralph Dills Park in Paramount on April 20 (Chris Dean), at the Piute Ponds on May 18 (Joe Lepisto), on San Clemente Island on May 30 (Johnny Galt) and on June 6 (Justyn Stahl) and at Tierra Bonita Park in Lancaster on June 3 (Andrew Lee).

Tennessee Warblers were found at the Piute Ponds on Edwards AFB on May 14 (Kimball Garrett), at Jesse Brewer Park in Los Angeles on May 24 (Kimball Garrett) and on San Clemente Island on June 2 (Nicole Desnoyers).

A Hooded Warbler, yet another southeastern vagrant, was discovered in Zuma Canyon on May 6 (Devon DeRaad).  Likewise were Northern Parulas recorded at Peck Road Water Conservation Park in Arcadia from April 22–23 (Jon Fisher) at the Village Green Condominiums in Los Angeles on May 20 and on June 10 (both Don Sterba).

An American Restart was at the Village Green on June 11 (Randy Ehler), a Magnolia Warbler was on San Clemente Island on May 26 (Justyn Stahl, Nicole DesNoyers), a Chestnut-sided Warbler was near Big Pines in the eastern San Gabriels on June 2 (Tom Benson) and a Blackpoll Warbler—more expected in fall—was at the Sepulveda Basin on May 20 (Sarah Ngo).

Palm Warblers included one at Banning Park in Wilmington on April 13 and again on April 22 (Philip Carnehl), two at Madrona Marsh first on April 15 and then from May 9–17 (Tracy Drake) and one at South Gate Park in South Gate on April 16 (Richard Barth).

Summer Tanagers were in Pasadena on May 24 (Darren Dowell) and at Apollo Park near Lancaster on May 30 (Wayne Martin).

A previously discovered Clay-colored Sparrow continued at Santa Fe Dam in Irwindale through April 15.

The wintering Harris’s Sparrow near Claremont was reported as late as April 28, while more common were a few continuing White-throated Sparrows with one recorded as late as April 28 at Sand Dune Park in Manhattan Beach.

San Clemente Island produced a Rose-breasted Grosbeak present from June 2–5 (Bernadette Ridgely).  Indigo Buntings included one at Madrona Marsh in Torrance on May 6 (Dinuk Magammana) and three different birds on San Clemente Island from May 29–31 (Justyn Stahl), with two continuing through June 3.

As well-birded as LA County may be, in truth we only scratch the surface of much of its 4,751 square miles.  Coverage is largely concentrated in more productive spots and in more easily accessible ones.  Opportunities for exploration and discovery remain plentiful. 

We all like to go places where we’ll see lots of birds, but areas such as the north slope of the San Gabriels beg for more exploration.  Improved habitat throughout these mountains offers great birding potential, but impacting access to the higher portions are repairs taking place on the Angeles Crest Highway.  The road will be closed from Islip Saddle to Blue Ridge Road until at least early July.  Even so, there are many other places to visit in the mountains and undoubtedly new discoveries to be made.    

Though summer has just begun and there’s plenty to occupy our time, shorebird migration is poised to begin in earnest.  By August southbound passerines will appear.  The lull between northbound and southbound birds is brief indeed.

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