Spring Banding Summary – March-May 2026
September 23, 2026
This summary was compiled by Point Blue’s Palomarin banding apprentices Peter Budko, Yuna Chita, and Kaia Hilgendorf-Roost with help from banding technicians June Yost and Sarah Needles, and banding supervisor Larissa Babicz.
Exciting Captures and Observations:
Ah, another wonderful spring at Palomarin. Along with an explosion of plant growth that we had to fight back to keep our trails clear, the season brought with it a new batch of apprentices, spring migrants passing through on their way north, and the arrival of summer resident birds ready to produce tons of cute baby birds for us to band.
The Black-headed Grosbeak is a beautiful bird that we rarely catch at Palo but is relatively common at some of our sites, and that we were excited to start catching this spring after their return from the tropics. This species exhibits pronounced sexual dimorphism in its plumage, meaning that adult males and females are easy to tell apart. As is often the case in sexually dimorphic birds, the male’s plumage is brighter and more colorful than the female’s as an indicator of evolutionary fitness. The male’s striking orange body, black wings with pronounced white wing bars, and eponymous black head contrast with the female’s more brown and streaky appearance.
Although we usually only catch songbirds due to the size of the mist nets that we use to capture birds, sometimes the stray raptor wanders into our nets, too! This spring we caught two Sharp-shinned Hawks – one at our site at Muddy Hollow in Point Reyes National Seashore and one at Redwood Creek, a site in the Golden Gate National Recreation Area near Muir Beach. Both were males, the smaller of the sexes. Most raptors show another type of sexual dimorphism where the females are often larger than males. Since smaller birds get caught more easily in our mist nets, most hawks that we catch are males. The hawk caught at Muddy Hollow, depicted below, was a young bird. Characteristics of a young accipiter include a yellow to orange eye and cinnamon-tipped, brown body feathers. Adults have orange to red eyes and slate-gray feathers on their back and wings.
We commonly hear the distinctive Pine Siskin flight calls as they fly over the Palomarin Field Station, but we rarely catch them since they spend much of their time flying overhead and perching high in the conifers. Luckily, one flew low enough to be caught in one of our mist nets! Pine Siskins have a gorgeous yellow bar on their wing and yellow edging on the flight feathers, which you can see especially well when the bird is in flight.
The first Red-breasted Nuthatches of the season were caught in May, and banders were excited to have two on the same day! Banders can determine whether a Red-breasted nuthatch is male or female by looking at the head color. The top of the head (crown) in females is gray, while that of males is black. There are feather characteristics that banders can look for to determine age.
Steller’s Jays are a common species found around the Palomarin Field Station and coastal scrub habitats of Point Reyes National Seashore. A handful are usually caught each year, and two were caught this spring. These birds are easily spotted and heard in the field due to their vivid blue plumage and loud, harsh calls. They are capable of producing an impressive array of different sounds, but their more common calls sound like a harsh “shack-shack-shack”. The blue color of their plumage is produced by the way the light rays reflect on the structure of the feather, rather than by pigments in the feather itself. The same is true for all other birds with blue feathers!
The Black Phoebe – another common species that we infrequently catch – sports a dark plumage with a black to dark gray head, wings, back, and tail, and a contrasting white belly. In May, we caught our first pair of juvenile Black Phoebes! One of the ways we can tell this is a juvenile is by the cinnamon wing bars (seen near the pointer finger in the picture below).
Brown Creepers are small arboreal songbirds with mottled brown backs to help them blend into the bark of trees. They climb up the trunks with ease by using their long claws for grip and their stiff tail for propping themselves against the trunks – much like woodpeckers. They use their decurved bill to eat insects and spiders in the crevices between the bark. We caught our first juvenile Brown Creeper of the season in May. We’ve been hearing them frequently around our net trails singing their song, which sounds like “Trees! Trees! Beautiful trees!”
This April, we caught a bird not commonly seen around Palomarin due to its rather secretive nature. MacGillivray’s Warblers usually hang out and breed in dense undergrowth usually involving riparian thickets of willow or alder, or forests with a moist, dense understory. They have a gray hood and white eye arcs, yellow belly, and olive-colored back and wings. The bird we caught was a female with a brood patch – a bare spot on the abdomen for more efficient heat transfer to her eggs – indicating that she is breeding somewhere nearby.
With the arrival of new spring/summer apprentices, along with migrating birds coming back to nest, the spring season was eventful and full of learning. The apprentices got up to date on Palo protocol and were thrilled to move into the summer season with new and improved banding skills.
Let’s Do the Numbers:
In 62 days (5358.8 net hours) of mist-netting at Palomarin in March, April, and May, we captured 221 new birds and recaptured 236 previously banded birds. A total of 457 birds of 33 species were caught. Approximately 7 birds were caught per banding day.
At our other West Marin banding sites, we captured 292 new birds and recaptured 190 previously banded birds. A total of 482 birds of 34 species were caught over 34 banding days in April (1341 net hours), an average of approximately 14 birds per banding day.
The highest capture rates at Palomarin and our other West Marin banding sites were on May 27th at Palomarin with 16 birds, and May 1st at Muddy Hollow with 32 birds.
At Palomarin, the following species were caught in the highest numbers: Wilson’s Warbler (80), Dark-eyed Junco (60), Song Sparrow (47), Allen’s Hummingbird (38), and Swainson’s Thrush (30).
Across all our other west Marin sites, the highest numbers of captures by species were Song Sparrow (98), Swainson’s Thrush (71), Yellow-rumped Warbler (66), Wilson’s Warbler (49), and Orange-crowned Warbler (16).
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 Marin County Parks, and to our surrounding Bolinas and West Marin County community and our funders for their support of our work.
Early-career bird banders are part of a rigorous training program at Point Blue’s Palomarin Field Station, where they learn to capture birds safely using mist nets and record data on each bird caught. The information collected allows us to better understand how populations of birds are doing and in turn gives us insight into the health of the systems we research. Learn more about our seasonal apprenticeships by visiting the careers page on our website.
All banding, marking, and sampling is being conducted under a federally authorized Bird Banding Permit issued by the U.S. Geological Survey’s Bird Banding Laboratory.
Our Palomarin Field Station is open to the public. Consider visiting us! Learn how on our contact & visit us web page.