Thursday, August 06, 2009

The 2009 migration season begins!

After winding up various summer field studies (including Long-billed Curlews, Flammulated Owls, and songbird counts all over south-central Idaho, we began our annual Lucky Peak fall songbird (and hummingbirds/woodpeckers too) migration study on July 16. On day 1, we captured 114 new birds plus 16 'recaptures' (birds already wearing bands - all placed there by us in this case) and were thus off to the races. We haven't equaled that total since but we've managed to keep 4 to 5 of us quite busy most days.

As usual, we have a great crew of full-time field assistants and part-time volunteers and here's a great example:
The crew on Wed, July 29 (includes several dedicated volunteers), from left: Gary, Dave, Carol, Heidi, Rob, Stephanie, Jack, Melody, and Jay

From July 16 to July 31, we captured 1,049 individuals of 31 different species. The top ten most abundant species were:
  1. Yellow-rumped Warbler (Audubon' subspecies): 129
  2. Dusky Flycatcher: 110
  3. MacGillivray's Warbler: 100
  4. Yellow Warbler: 88
  5. Nashville Warbler: 79
  6. Chipping Sparrow: 71
  7. Ruby-crowned Kinglet: 64
  8. Lazuli Bunting: 53
  9. Spotted Towhee: 42
  10. Hammond's Flycatcher: 39
#11 on the abundance ranking is the Calliope Hummingbird, with 38 individuals captured in July - already the 3rd highest season total in 13 seasons of this study! We've also captured a record 13 Black-chinned Hummingbirds so far (5 of them since July 31) and this represents our highest season total to date. Thus, it seems its been a good year for the nectarivores!

Up close and personal with an immature male Calliope Hummingbird
Other highlights so far include a juvenile-plumaged Green-tailed Towhee on July 29th - only the 5th we've ever captured at Lucky Peak (too sneaky for a photo ;-).

As usual, the bulk of early-season captures include locally-dispersing juveniles and some molting adults but we've also had a slow but steady push of southward migrants all along, especially including the hummingbirds plus adults of Dusky Flycatchers, Western Tanagers, Black-headed Grosbeaks, and Warbling Vireos.
4 juvenile Dusky Flycatchers (all caught in the same net) on their way back to their capture location - photo by Heidi Ware

Then, during the first few days of August, we started to catch the 2nd wave of migrants, including our first 'Western' Flycatcher and Wilson's Warbler on Aug 1, Gray Flycatcher and Western Wood-pewee on Aug 2, and Townsend's Warbler on Aug 3. Also, in the last few days, immature Yellow Warblers (usually our earliest warbler to push southward) have started putting on big fat stores (migratory fuel)!
Adult 'Western' Flycatcher (likely Cordilleran by range) - photo by Jack Stenger

Adult Gray Flycatcher

Immature Western Wood-pewee

We usually experience a bit of a lull in #s during early August (but still great diversity) as the dispersing young birds molt their body plumage and adults of many species continue molting flight feathers in prep for migration. Then, more species will begin migrating in earnest over the next couple of weeks. Then the raptor excitement begins in late August when we begin hawk counts on Aug 25 and owl netting on Aug 28.

Golden Eagle Audubon has a field trip planned for Sat, Aug 15 and this would be a great time to see many colorful birds up close!

Cheers & happy fall!

Jay

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Mission: to contribute to the conservation of western migratory landbirds through cooperative research and public education