Migration Monitoring Back in Session

The most intense fall landbird migration generally occurs during the last third of September and the first half of October along the Lake Erie coastline. Fall 2013 was shaping up to be one of the best on record as we passed through September. The Navarre Banding Station is located on private property but there is a management agreement with the U.S. Fish and Wildlife Service resulting in closure when the government shutdown on October 1^st. With that went our field work. Sixteen days, of what appeared to be very good bird movement was lost. 

On October 17^th the study site could again be opened. Important data lost was the transition from the September speciation and the mid-October community. Warbler diversity reduced and the Blackpoll changed over to the Myrtle; Swainson’s and Gray-cheeked gave way to Hermit Thrush; Kinglets, Winter Wren, and creepers arrived to replace vireos and the warbler diversity as sub-dominants. When was the change over? What was the volume and how does 2013 compare to normality? In terms of the data, it was a major hit to a long-term study. 

 

Hermit Thrush (HETH) left with reddish wings and less apparent eye ring than the Swainson's Thrush (SWTH) right with buffy obvious eye ring.

HETH Left with brown back and reddish tail and SWTH right with brown back and tail

It is consistency that is the greatest value for migration interpretation.   

Can the loss of days and data be overcome? Those are big questions. We are hoping weather allows for a ten day to two week block of field work to have strong pre and post closure data sets to look at. We will be looking at our satellite stations and maybe turn the table and have them represent the control to assess bird movement this October. Big questions, the long-term data has never been more important and now we have new variables. Stay tuned as we work through these new complications.

Highlights for October 17-20th were seven species of warbler including Black-throated Blue, Myrtle, American Redstart, Tennessee, Nashville, and Blackpoll. 

Male Rusty Blackbird with its "rusty" basic plumage which feathers will wear off "rust" color by spring to leave a nice iridescent black feathered head.

The first appearance of Fox Sparrows arrived at the Navarre Station along with a couple Red-breasted Nuthatches being observed. Look forward to the cold fronts to likely bring the American Tree Sparrow from its northern territory.

Fox Sparrow (FOSP) - note bi-colored bill and distinct spots on breast

Back of FOSP showing the diagnostic "red" tail of Fox Sparrows

Highlights from September 16th- 22nd 2013

"When the gales of November come early." A cold front from the northwest is the favorable direction for good fall migration. A major front with extensive rain arrived Friday night departing just before daybreak Saturday morning. Often migrants "balloon in front of the rain front but just as often they follow right on its heels as if drafting the pressure and precipitation change. This scenario is just what happened Saturday morning; and what a day Saturday was! Untold numbers of warblers and some thrushes could be heard calling the hour before light as they descended to land following the early morning lake crossing.

Blackpoll Warblers (BLPW) were arriving in flocks, and not to be outdone, the Cape May Warblers (CMWA) arrived in numbers we haven't seen for quite a few years. An additional 18 warbler species wee recorded that day or earlier in the week and included: Tennessee (TEWA), Nashville (NAWA), Yellow (YEWA), Chestnut-sided (CSWA), Magnolia (MAWA), Black-throated Blue (BTBW), Myrtle (MYWA), Black-throated Green (BTNW), Blackburnian (BLBW), Bay-breasted (BBWA), Black-and-white (BAWW), American Redstart (AMRE), Ovenbird (OVEN), Northern Waterthrush (NOWA), Connecticut (CONW), Common Yellowthroat (COYE), Wilson's (WIWA), and Canada (CAWA). 

Below is a closer look at the CMWAs from Saturday. There was a boatload (or in this case a sky and shrub load) of them around. This species is highly variable in plumage in fall.

Cape May Warblers: adult male left and adult female right.
Note fine streaks on breast and small pointed bill.

Some highlights from the week:

Blue-headed Vireo

Connecticut Warbler:adult male with complete white eye ring.Two CONWs were captured and banded on 9/21/13

Stay tuned for another week of increasing numbers of Blackpoll Warblers. Keep that dog-eared page of confusing fall warblers handy! Prepare for the October birds: kinglets, sparrows, and blackbirds to start cranking up. 

Please mark your calendar and join us for a free public banding demonstration at BSBO next Saturday from 10:00 AM - 11:30 AM. 

Highlights for the Week of September 9th- 15th

This week saw an increase in bird species and volume from the weeks prior. The presence of a series of cold fronts from the northwest resulted in excellent migration in the Great Lakes. Higher numbers of thrushes, and Blackpolls (BLPW) and Tennessee Warblers (TEWA) headlined along with 21 other species of warblers including: Golden-winged (GWWA), Nashville (NAWA), Chestnut-sided (CSWA), Magnolia (MAWA), Cape May (CMWA), Black-throated Green (BTNW), Black-throated Blue (BTBW), Myrtle (MYWA), Blackburnian (BLBW), Western Palm (WPWA), Bay-breasted (BBWA), Blackpoll (BLPW), Black-and-white (BAWW), American Redstart (AMRE), Ovenbird (OVEN), Northern Watertrhush (NOWA), Connecticut (CONW), Mourning (MOWA), Common Yellowthroat (COYE), Wilson's (WIWA), Brewster's and Canada (CAWA). What a list! It was the first for this fall for the Western Palm, Golden-winged, Brewster's, and Myrtle Warblers. 

As promised from last week, here is a review of Brown Thrush ID for those species at their peak now. Veery (VEER), Swainson's (SWTH) and Gray-cheeked Thrushes (GCTH).

A few key field marks for identifying the brown thrushes are the appearance of eye ring, the spotting on the chest, and the color of the back. 

Left bird has a visible eye ring.  The right bird does not.

Bird on left is the only bird with an eye ring in this photo.
Note the differences in overall color as well. 

Then note the coloration of the head, back, and tail. Is it olive brown or reddish brown?

Back coloration of these birds are both olive brown

Back coloration on these birds are left olive brown and right reddish brown. Notice the markings of the secondary coverts on the bird on the right, this indicates a hatching-year bird and can give the appearance of a wing bar on some individuals.

Compare spotting on these and look for eye rings. Bird in center has blurry spots. Also appears more reddish brown than the other two.
Left to Right: Swainson's Thrush, Veery, and Gray-cheeked Thrush. 

Of the two olive-brown backed thrushes, one has an eye ring and one does not. The one with the eye ring has an "i" in its name: Swainson's. Also a Swainson's has a "buffy " eye ring and buffyness to its chest. The other olive brown thrush with no eye ring is the Gray-cheeked Thrush (GCTH).
Guess which ones are here:

Birds from left to right: SWTH VEER GCTH

For those who would like to see some of these fall migrants up close, we will be holding a free public banding demonstration at the Observatory this weekend, both Saturday and Sunday from 10:00 AM - 11:30 AM in conjunction with Midwest Birding Symposium.

Also check online for the update on the banding totals for this fall.  http://www.bsbo.org/passerine/pdf/passerinebandingfall2013navarre.pdf