Sunday, October 19, 2008

Songbird season totals (& raptor update)

We finished up the songbird migration season on Wednesday, October 15 and I just finished tallying up the #s. We captured a total of 5,158 birds of 56 species. Though this is certainly an impressive number, it's actually our lowest capture total since 2003 and the capture rate (birds per netting effort) is a bit lower than the long-term average. Much of this can be attributed to lower-than-average seasons for Ruby-crowned Kinglet and Dark-eyed Junco - our two most frequently-captured species over the duration of the migration study. On the other hand, we experienced a HUGE year for Yellow-rumped Warblers (more than double the long-term average and, by far, a new record) that included a record 9 of the 'Myrtle' subspecies (we had never caught more than 2 in a season before!).

Our top ten were:
  • 1) Ruby-crowned Kinglet 797
  • 2) Yellow-rumped Warbler 632
  • 3) White-crowned Sparrow 458
  • 4) Dark-eyed Junco 334
  • 5) MacGillivray's Warbler 274
  • 6) Dusky Flycatcher 254
  • 6) Nashville Warbler 254
  • 8) Western Tanager 253
  • 9) Chipping Sparrow 245
  • 10) Yellow Warbler 221

The only new species to grace our nets this year was a Varied Thrush captured on October 13. This is a species that I observe one or a few of in most years at Lucky Peak during late September and/or early October but we just hadn't caught one before. Given that Varied Thrushes are known to consume fruit and our nets are placed among fruiting shrubs, I've been a little surprised to have not caught one yet. On the other hand, our nets are more designed for the smaller songbirds and many robin-sized birds likely escape ....

Immature male Varied Thrush (photo by Kaia Colestock)

Other highlights from the season included a Blackburnian Warbler (Sept 2 - our 3rd ever at Lucky Peak and a 6th state record), an American Redstart (Sept 14), a Magnolia Warbler (Sept 21 - only our second at Lucky Peak), 2 Golden-crowned Sparrows, and 2 Broad-tailed Hummingbirds (only the 2nd & 3rd we've ever caught).

On October 9 we captured our second Savannah Sparrow of the season (and only our 9th in 12 years - see below). It looks like one of the darkest subspecies and, in some ways, resembles a Lincoln's Sparrow.

Savannah Sparrow on 10-9-08 (photo by Mike McDonald)

In contrast, check out the Savannah Sparrow we captured on 9-18-08 (photo by Jake Schas) - note that the lighting is different in each photo but, notwithstanding, there is a noticeable difference in coloration (& if you click on each photo, you can get a better look at each bird)

In other news, the diurnal raptor flight has really slowed down since the big storm of Oct 10-11. Even though the raptor #s tend to be lower from Oct 10 on in each season, we usually see some decent flights (50-100 birds/day) on good weather days and the numbers this year are much lower than usual for this time of year. That said, this is the time of year when we see some 'sexy' species or subspecies including Rough-legged Hawks, Harlan's race of Red-tailed Hawk, Northern Goshawk, and Merlin.

The owl crew is still catching a handful of Northern Saw-whet Owls and we did have a record year for Flammulated Owls (at least 60).

I will post final tallies for the raptors after the season finishes on Oct 31.



Saturday, October 11, 2008


My apologies for the long delay between posts ... migration has continued in full swing for songbirds, owls, and hawks and I'll try to post more details soon.

BUT, the big news is that today during hawk-trapping, I was fortunate enough to capture and band an immature gray phase Gyrfalcon at Lucky Peak. This is the first we have ever seen or captured during the 14+ seasons of raptor monitoring in the Boise Foothills. Thus, it was a pretty special experience to watch the bird for a few minutes as it worked through the trapping station before finally getting captured! The early date is also amazing as it seems that late October/early November are when migrants tend to arrive to this region. Presumably the strong cold front (see snow in background) has something to do with it.

The bird was in fantastic shape (weighed over 1600 grams) and was last seen flying W over Boise so keep your eyes peeled!

In other news, winter finches are around in big #s - esp. including Evening Grosbeaks and, lately, Red Crossbills. There have even been a couple sightings of apparent Common Redpolls (seems early too) that I have yet to see or hear ... hopefully soon.

OK, more soon ... enjoy the few pics below .... (in case you're wondering, the blood on my finger is mine - not the bird's - from where it punctured my finger with it's very sharp bill!).



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