Point Blue's Palomarin Blog

Taking the Long View: An inside look at the goings-on at the longest running avian ecology field station west of the Mississippi.

Monthly Banding Summary, July 2015

09.15.15
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This summary was compiled by Palomarin banding interns Robert Snowden and Hannah Conley with help from Renée Cormier, Banding Supervisor.

Exciting Captures and Observations:

The long summer days persist—breeding season winds down and a lot of unbanded juveniles show up. Activity is notably slower and quieter by the end of month, and the summer season draws to a close.

While much of the July persisted with a steady influx of young birds of local breeding species, it started off with a bang—our first capture of the month was an adult Varied Thrush, caught early in the morning at Palomarin on July 1st. This was a rather surprising bird for the middle of the summer—while the species is common in the region during the winter, it spends its summer much further north in the Pacific Northwest and typically does not return until later in the fall. Our individual was the first of its species ever caught at Palomarin between the months of June and August. This sudden appearance prompted some speculation—perhaps its breeding attempt failed and it was heading back early to its nonbreeding grounds.

Adult male Varied thrush caught at Palomarin in July. Photo by Tyler Winter.

One noticeable trend we observed this month was a change in proportion of new, unbanded birds caught relative to previously banded ‘recaptured’ birds. Across our sites in July, we captured twice as many new birds as we did recaptured birds; while from March to June, the ratio of new birds to recaptures was about even. Such a marked change in that ratio can be expected in the late summer, when recently-fledged juvenile birds are abundant and beginning to disperse from the grounds where they hatched. We expect to catch a lot more of these young birds in the coming months.

Other noteworthy captures this month included a Belted Kingfisher, Western Tanager, and Blue-gray Gnatcatcher all at Palomarin, and a Marsh Wren at Pine Gulch.

Adult female Belted Kingfisher caught at Palomarin. Photo by Hannah Conley.

Let’s Do the Numbers:

In 26 days (2881.90 net hours) of mist-netting at Palomarin in July, we captured 93 new birds and recaptured 83 previously banded birds. A total of 176 birds of 32 species were caught this month. Approximately 7 birds were caught per banding day.

At our other West Marin banding sites, we captured 355 new birds and recaptured 141 previously banded birds. A total of 496 birds of 34 species were caught over 16 banding days this month (913.26 net hours), an average of approximately 31 birds per day.

Adult female Western Tanager caught at Palomarin. Photo by Robert Snowden.

The highest capture rates at Palomarin and our other West Marin banding sites were on July 11th at Palomarin with 13 birds and July 1st at Pine Gulch with 72 birds.

At Palomarin the highest numbers were captured for the following species: Wrentit (49), Swainson’s Thrush (29), Wilson’s Warbler (11), Brown Creeper (11), and Anna’s Hummingbird (10).

Across all off-sites, the highest numbers of captures by species were: Swainson’s Thrush (133), Song Sparrow (114), Wilson’s Warbler (67), Wrentit (33), and Allen’s Hummingbird (23).

First-year Blue-gray Gnatcatcher caught at Palomarin. Photo by Hannah Conley.

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.

First-year Marsh Wren caught at Pine Gulch, on the Marin County Open Space District's Bolinas Lagoon Preserve.

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