(Back to front) Long-billed Dowitcher, Dunlin, Least Sandpiper, Jackson Bottom Wetlands Preserve, Hillsboro, Oregon on May 4, 2010 by Greg Gillson.
Wow! This first week of May has certainly been filled with birds! Each showery day with southerly winds brought in more neotropical migrants and shorebirds. This is the peak of spring migration. The 7 days from Friday, April 30 to Thursday, May 6 recorded over 100 species at Jackson Bottom Wetlands Preserve in Hillsboro, Oregon!
The first local BLACK-HEADED GROSBEAKS and WESTERN TANAGERS of spring arrived. The first local GREEN HERONS of spring were spotted on May 2.
This week has seen an increase of migrant shorebirds. Especially noteworthy were the lone SOLITARY SANDPIPERS seen a couple of days. These have a very narrow migration window, approximately April 20 - May 8. They are also not common and hide themselves in the grassy fringes of the marsh in shallow water. Total numbers of shorebirds are low at Jackson Bottom, as mudflats are not extensive. However, the variety has been good. Single LESSER YELLOWLEGS, SEMIPALMATED PLOVERS, and SHORT-BILLED DOWITCHERS (5/5) joined some of the more numerous species.
Warblers were conspicuous migrants this week, with NASHVILLE WARBLER (4/30), MACGILLIVRAY'S WARBLER (up to 4 birds on 5/6; photo above, left), and YELLOW WARBLERS among the normally less-frequently reported warblers of Jackson Bottom that were seen this week. Many migrant WILSON'S WARBLERS (photo above, right) were along the Tualatin River this week. Hundreds of YELLOW-RUMPED WARBLERS continue to be found.
Nearly 1,000 VAUX'S SWIFTS were over the wetlands amid the showers of May 3. CLIFF SWALLOW numbers were in the several hundreds on a couple of days. A rather locally rare pair of PURPLE MARTINS (photo, right) were present most of the week. They could remain to nest, or move on--we'll have to wait and see. A HERMIT THRUSH showed itself on 5/6 (photo, left).
A first record for the Preserve, and only the 7th record for Washington County, a DUSKY FLYCATCHER was present on May 5.
Here is the list of the bird species seen this week.
Greater White-fronted Goose
Great Blue Heron
Northern Rough-winged Swallow
Black-throated Gray Warbler