A slow, yet surprising September
September 29, 2019
Over the last four weeks, unfavorable wind and visibility have greatly diminished the ability of western migrants and eastern vagrants to arrive on Southeast Farallon Island this fall. Warbler, vireo, and flycatcher diversity and numbers are particularly low: 12 species of warblers, 0 species of vireos, and 5 species of flycatchers have been observed so far. Despite dismal migration conditions, we’ve had great fortune during our daily seawatches! Great numbers of ARCTIC TERNS were observed flying by the island in early September, including a flock of 100 individuals on the evening of the 3rd. Frequent sightings of Arctic Terns this year parallel general trends along coastal California this fall. It’s also been an exceptional year for LONG-TAILED JAEGER; six individuals have been seen so far this season, including four in one evening. The crew has had fantastic luck with SABINE’S GULL, too!
Though “wave days” have been nearly non-existent, several exceptional birds have delighted us. Beginning on the 3rd, the earliest TOWNSEND’S SOLITAIRE in the island history was spotted in Owl Chute.
The next day, the 4th, Jim woke everyone up at 0700 via radio when he discovered a CASSIN’S SPARROW at the lighthouse. After an exhausting climb up the hill, only a few of us got the briefest of views before it dove down the hill. Luckily, it was rediscovered the next day near the burning bush and gave every stellar looks.
Over a week passed before the next great birds showed up. On the 12th, Amanda discovered a BANK SWALLOW flying around the lighthouse with a Barn Swallow, the first record since 2005. Unfortunately this one was too quick for photos. Later that day, an undetected PAINTED BUNTING was captured while mist netting. The lack of wing wars and bright green formative feathers on the back is diagnostic for this species. Painted Bunting had not been detected since 2014.
Continuing on the vagrant vibe, the next day, the 13th, another surprise individual was captured while mist netting. After several grueling minutes of wing morphology measurements, we realized we were holding a YELLOW-BELLIED FLYCATCHER. This is another species not detected since 2014.
An Olive-backed SWAINSON’S THRUSH was also captured that day, a race not readily encountered in California despite breeding in the eastern Sierra.
On the 15th, John discovered a BLACK-THROATED SPARROW bopping around in Owl Chute, another great species not seen on the island since 2016.
Owl Chute delivered again on the 18th when Kurt spotted a HAMMOND’s FLYCATCHER flitting about the rocks. This empid can be difficult to separate from Dusky in the field, but we were lucky enough to capture it minutes later. Great identification, another great bird for 2019!
Another one for the 18th, Amanda found a WHITE-WINGED DOVE at the saddle, sitting long enough for everyone to see it.
The next surprise happened on the 21st when four WHITE-THROATED SWIFTS made a brief lap around Lighthouse Hill during Amanda’s shark watch. And our most recent, tasty birds arrived on the 26th when seven WHITE-FACED IBIS were spotted flying in and around Maintop Bay, another one spotted during an Amanda shark watch session.
Stay tuned to hear about more late September surprises, including a recent “wave day” with nice warbler and vireo diversity and the start of our annual Farallonathon!
BTSP, CASP, HAFL, WWDO, PABU, SWTH, and YBFL photos by John Garrett, 2019.
TOSO photo by Amanda Spears, 2019.