Monthly Banding Summary, March 2016
By Palomarin Field Station
This summary was compiled by Palomarin banding interns Anna Kennedy and Garrett Duncan with help from Mark Dettling, Banding Supervisor.
Exciting Captures and Observations:
On March 22nd, we caught our first “Western” Flycatcher of the season at Muddy Hollow (in Point Reyes National Seashore). The “Western” Flycatcher is actually two closely related species, the Pacific-slope Flycatcher and the Cordilleran Flycatcher. In California, the Pacific-slope Flycatcher breeds west of the Sierra Nevada Mountains and Cordilleran Flycatcher to the east. These two species cannot be differentiated in hand by their appearance alone so a series of measurements are taken to help determine the species. Each does have a unique song so identification can be easier in the field than in the hand!
As more spring migrants arrive and the breeding season picks up, our capture rates are increasing from the winter months. Also, we are seeing birds in breeding condition, indicated by the presence of developed brood patches, meaning they are tending to an active nest, or cloacal protuberances in preparation for procreation. Generally, birds with brood patches are females and birds with cloacal protuberances are males, but there are a few exceptions including one of our study species, the Wrentit, which can have both at the same time!
Our first Wilson’s Warbler of the season was caught at the Palomarin Field Station on March 20th! Wilson’s Warblers begin their journeys in the Neotropics and migrate northward each spring. Some will breed here, others may be passing through to breeding grounds further north. The individuals who breed within our study area will be closely scrutinized by our nest searching interns to find and monitor their nests, eggs, and nestlings as they develop.
Other exciting captures included a Red-shafted Flicker at Uppers (an offsite location within the Palomarin study area) and a Sharp-shinned Hawk at Palomarin on March 7th, three Tree Swallows at Pine Gulch (in the Bolinas Lagoon Open Space Preserve) on March 16th, a Red-breasted Nuthatch at Palomarin on March 23rd, a Varied Thrush at Palomarin also on March 23rd, two American Goldfinches at Pine Gulch on March 29th, and a Common Yellowthroat at Muddy Hollow (in the Point Reyes National Seashore) on March 31st.
Let’s Do the Numbers:
In 15 days (1388.49 net hours) of mist-netting at Palomarin in March, we captured 17 new birds and recaptured 18 previously banded birds. A total of 35 birds of 16 species were caught this month. Approximately 3 birds were caught per banding day.
At our other West Marin banding sites, we captured 34 new birds and recaptured 51 previously banded birds. A total of 85 birds of 25 species were caught over 12 banding days this month (583.03 net hours), an average of approximately 8 birds per day.
The highest capture rates at Palomarin and our other West Marin banding sites were on March 30th at Palomarin with 9 birds, and March 16th and March 29th at Pine Gulch tied with 16 birds.
At Palomarin the highest numbers were captured for the following species: Orange-crowned Warbler (7), Chestnut-backed Chickadee (5), Wilson’s Warbler (4), and Oregon Junco (3).
Across all off-sites, the highest numbers of captures by species were: Fox Sparrow (14), Song Sparrow (14), Pacific Wren (8), Wilson’s Warbler (8), and Common Yellowthroat (5).
About these Summaries:
In an effort to share our science with the public, Point Blue interns and staff at our Palomarin Field Station (Palomarin or “Palo”) in Point Reyes National Seashore near Bolinas, CA produce these monthly bird-banding summaries. Our science interns create these summaries as part of their science outreach training.
Our Palomarin Field Station is open to the public. Consider visiting us! Learn how by visiting our mist-netting demonstrations web page.