Date: 6/16/19 6:48 pm
From: <clearwater...>
Subject: [obol] Comment on eRBA for Multnomah Co. Vesper Sparrow
First, thanks to the Multnomah County eBird reviewer for setting the filters so that reports of Vesper Sparrows get flagged for details. Due to the arguably Threatened/Endangered status of the subspecies that nests in western Oregon, "Oregon" Vesper Sparrow (ORVESP), it's important to make sure that "false positives" (reports of this species that may have been something else) don't end up in the database.

In the case of the June 14th report that showed up in today's compendium of recent eRBAs, the identification seems to have been based on observation of a "[s]parrow with distinct white outer tail feathers." I'm not familiar with the Portland Japanese Garden, but when I think of Japanese gardens, that image doesn't bring to mind Vesper Sparrow habitat. I note that Oregon Juncos have been reported at this site through the nesting season. At this time of year, juvenile juncos are easily confused with Vesper Sparrows as both are have streaky brownish heads and distinct white outer rectrices.

This prompted me to check what other reports of Vesper Sparrows have gone under the radar in the Willamette Valley so far since the beginning of May (i.e., the nesting season, by which time it's safe to assume that migrants have moved on).

Lane County has 5 reports, none of which contain any details about how the birds were identified (even whether seen or heard). Two independent reports from Fern Ridge (Royal Ave) in early June are especially interesting -- there is suitable habitat there and it would be good to know if Vespers are nesting there this year. Another at Lane Memorial Gardens on 5/21 seems more like a wandering type of situation, certainly not the type of habitat where I'd expect a Vesper Sparrow to stick around.

Clackamas County has a cluster of about a dozen reports, mainly by an observer who I know has been carefully monitoring this species one a particular farm that seems to still have a small nesting population, year after year.

Linn County has a cluster of 7 reports in the Belts Rd. area, three of them with good photos (two good enough to see that these were unbanded birds). This has long been a good place to find these birds.

Marion County has 1 report, which I just added today. I included a brief note on how I identified this bird (heard only).

Benton County has 9 reports, only 2 of which have any documentation. Most of these reports are clustered either around Christmas tree farms along Bellfountain Rd. or Bald Hill Natural Area/farm where we know there are populations, so I'm not worried about those.

A single report from 5/9 at the North Prairie on Finley NWR is interesting, since we have no recent evidence of nesting on any of the mid-Willamette Valley refuges in recent years/decades. Unfortunately this report gives no details, not even a mention of whether the bird was seen or heard.

There is also a 5/4 report from a student apartment complex in the middle of Corvallis, just south of Corvallis. That one does contain a photo and this description: "I heard the call and saw it high in a tree. Was able to use camera to see defining feature like it's beak and underbelly" (sic).

The photos shows an underside view of a drab brown streaky bird with a short tail, sitting on a wire. I'm not sure what kind of bird this is -- maybe a female House Finch? It might make a good bird ID puzzle, for folks who enjoy trying to identify birds from marginal photos. But it's certainly not a Vesper Sparrow. Yet it shows up in the database alongside of the more credible reports.

Bottom line, I appreciate that the Multnomah County reviewer has tightened up the standards for accepting Vesper Sparrow reports. It doesn't do any good for conservation efforts, to have false positives going into the database without any kind of review. I encourage the other county reviewers in the Willamette Valley region (and also in the Umpqua, Rogue and South Coast regions) to tighten things up. At a minimum, we should expect a basic note on whether a reported Vesper Sparrow was seen or heard, or both. At locations away from known nesting sites, there should be enough information to be sure that other common suspects such as Song Sparrow, Bewick's Wren, and juvenile juncos have been ruled out.


Joel Geier
Camp Adair area north of Corvallis

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