Fall Season Banding Summary, August-October 2022

December 29, 2022

This summary was compiled by Point Blue’s Palomarin banding apprentices (Sam Rapp, Anna Douglas, Cristobal Castañeda, and Greyson Poutas) with help from Mike Mahoney, Banding Supervisor. 

 

Exciting Captures and Observations:

Between vagrant birds, annual migrants, and the return of winter residents, this has been an eventful fall season at the Palomarin Field Station. In August, the Spring-Summer banding apprentices and summer UC Davis interns assisted with training the newly hired Fall-Winter cohort to collect valuable data during the busy migration season. Additionally, the Fall Season at Palo came with exciting events and celebrations like the 44th annual Bird-a-Thon and our Golden-Crowned Sparrow Party!

The most riveting moment at Palomarin this fall was when a young Wood Thrush was captured during a banding demonstration for other Point Blue staff on October 12, 2022. Wood Thrushes have a distinct orange-brown head and a white chest with bold black spots, and are larger compared to the Hermit Thrushes and Swainson’s Thrushes we normally capture at this time of year. The Wood Thrush’s range is exclusive to eastern North and Central America, and is rare to see in the midwestern United States – let alone on the west coast here in the Point Reyes National Seashore. 

With this in mind, staff biologists knew this was a rare capture, but was it the first Wood Thrush capture at the station? Upon investigation in our long term data set, we discovered the first Wood Thrush was caught on June 18, 1977 – 45 years ago – making this the 2nd Wood Thrush capture at Palomarin! Our excitement sustained throughout the day as we kept an ear out for our beloved Wood Thrush.

 

Palomarin’s “off-site” banding stations around West Marin are also subject to capturing vagrants (migrant birds who are observed outside of their expected range) between August to October. A Tennessee Warbler flew into a net at Redwood Creek – a riparian study site dominated by Arroyo Willows and Red Alders in the Golden Gate National Recreation Area near Muir Woods. Tennessee Warblers are considered to be vagrants in this area of the world, as they spend their summer in Canada and migrate through the East coast, though we expect to see at least one in the field every few years in West Marin. 

Another riparian “off-site” where we band regularly is Muddy Hollow in Point Reyes National Seashore. This fall at Muddy Hollow we caught a Black-throated Gray Warbler, who are distinguished by their black and white striped facial pattern – a regular migrant here and even a breeder elsewhere in Marin County, but always a pleasure to see in the hand. We also caught a Hammond’s Flycatcher, which has a grayer complexion, smaller bill, and differences in wing feather shape and length that are measurable in hand compared to our typically captured and closely related Pacific-slope Flycatchers. Some do migrate along coastal California, but the rarity of their capture makes them fun to see in the nets (they are also fun, and sometimes challenging, to identify). We also enjoyed catching yet another regular migrant that we also do not typically encounter many of in any season: a Cassin’s Vireo, at our riparian banding station at Pine Gulch at the Bolinas Lagoon Open Space Preserve.

 

 

Besides the excitement of vagrancy and annual migrants, fall at Palomarin also means welcoming back species who come and stay here for the winter. Our winter residents include Golden-crowned Sparrows, Fox Sparrows, White-throated Sparrows (uncommon but regular), Lincoln’s Sparrows, Hermit Thrushes, Townsend’s Warblers, and Ruby-crowned Kinglets. We always look forward to capturing our first Golden-crowned Sparrow of the season, and even have an endearing tradition every fall: a party on their behalf celebrated at Palo around the time of their return! The first Golden-Crowned Sparrow was captured this year on September 27 and our staff held a small gathering on October 5th. Wintering birds will stay at Palomarin for the next few months before migrating back up north to their breeding grounds in Alaska in the spring (in fact, check here for where our Golden-crowned Sparrows go, here for where our Fox Sparrows go, and here for where our Hermit Thrushes go!). 

 

 

Let’s Do the Numbers: 

In 86 days (8897.35 net hours) of mist-netting at Palomarin from August to October, we captured 935 new birds and recaptured 417 previously banded birds. A total of 1352 birds of 63 species were caught. Approximately 17 birds were caught per banding day. 

At our four other West Marin banding sites (our “off-sites” mentioned above), we captured 946 new birds and recaptured 419 previously banded birds. A total of 1365 birds of 65 species were caught over 46 banding days in August to October (2456.5 net hours), an average of approximately 30 birds per day.

The highest capture rate at Palomarin was on August 30th with 32 birds. Our other West Marin banding sites saw a high count of 46 birds at Redwood Creek on October 27th.

At Palomarin, the following species were caught in the highest numbers: Hermit Thrush (121), Pacific-slope Flycatcher (65), Wrentit (57), Brown Creeper (56), and Townsend’s Warbler (38).

Across all off-sites, the highest numbers of captures by species were: Song Sparrow (236), Hermit Thrush (80), Wrentit (63), Swainson’s Thrush (60), and Fox Sparrow (46).

 

About these Summaries:

Point Blue apprentices and staff at our Palomarin Field Station share these blog posts in an effort to further engage the public in our science. We are grateful to our partners at the Point Reyes National Seashore, Golden Gate National Recreation Area, and Bolinas Lagoon Open Space Preserve; to our surrounding Bolinas and West Marin community; and to numerous Point Blue and Palomarin supporters, for their support of our work.

 

Our Palomarin Field Station is open to the public. Consider visiting us! Learn how on our “Contact & Visit Us” web page.