Thursday, October 2, 2014

First half of fall migration

August has been an exceptionally busy month compared to previous years with productivity of some species such as Gray Catbirds, Yellow Warblers, Song Sparrows, and Downy Woodpeckers being quite a bit above average. The majority of these birds were not migrants but began their life on Wing Island.

Eastern Phoebes began showing up at the end of July and we banded 28 young birds in August. The cinnamon-edged coverts are present in young birds (shown below) before their preformative molt. After molting the edging will be a dingy gray color and the light colored breast will be more yellow.

Bander assistant Ron Kielb was excited to band his 1,000th bird, a Northern Waterthrush!

Numerous flycatchers were banded in August and September- Yellow-bellied, Acadian,but mainly Traill's (shown below).

We banded two Mourning Warblers in August, the first being on 16 Aug. This one was a puzzle as it had such a wide, almost complete eye ring, but it was really too small to be a Connecticut Warbler and it had an interrupted breast band. MacGillvray's Warbler has a wide eye ring but it too is partial. Any thoughts are greatly appreciated.

Pictured below is another Mourning Warbler with an eye ring more typical to the species, broken and thinner.

We banded 4 American Redstarts in August with the first showing up on the 16th, all HY (hatch year) birds. 

The 18th brought our first of only two Ovenbirds. We typically band more of these birds in fairly good numbers. 

Occasionally when I'm home trapping hummingbirds in my yard I get other visitors including Baltimore Orioles like this adult male and female that were coming into feed on the sugar water.

Hatch year Black-and-white Warblers can be tricky sometimes to sex. We captured this female on the 20th. Both males and females can have white throats but usually males have darker streaking to the sides as opposed to the dull-colored streaking of this female. Her flanks and cheeks showed some buff coloration also.

We also captured a HY Saltmarsh Sparrow, maybe an offspring of the male we caught in July, 

and a Warbling Vireo with the rather indistinct facial pattern.  

The cardinal pictured below was suffering from a bad case of head lice or mites but I thought it showed a good picture of what birds' ears look like.

In the fall it is easy to tell young Red-eyed Vireos from the adults because their eyes are still brown. Shown first is the adult with the HY bird below.

The Brown Thrasher is another species that we can age by eye color. We were fortunate to have them breeding on Wing Island this year possibly due to the growth of the meadow that hasn't been mowed in a few years. They like to breed in thickets. The young have a grayish eye color

that becomes yellow as an adult like this female that we recaptured on 29 Sep. She was the same one we banded in July with a full brood patch. 

Adults can also have a pseudolimit in their greater coverts making them sometimes difficult to age in the spring. They have both white and buff-edged greater coverts.

As juveniles, Northern Mockingbirds will also start out with grayish eyes

that will become a dull yellow as they molt into preformative plumage and 

change to a brighter yellow as an adult. 

We heard very few kingbirds vocalizing this summer so we were happy to finally capture one on the 30 Aug. The young don't have the orange crown like the adults do.

We had our busiest day so far of the season on 31 August with 148 birds netted, half being Gray Catbirds of course! We also captured a young Marsh Wren still undergoing a preformative molt, our earliest ever for this species during fall migration.

August was quite a busy month with 1260 birds netted of 38 species. September then waned with numbers and variety of warblers and other species quite low possibly due to the many days of NE winds and quite breezy. We had our 2nd Acadian Flycatcher on the 3rd 

along with a Blackpoll Warbler (not shown), our first of two HY male Black-throated Green Warblers

and our one and only (so far) Black-throated Blue Warbler, a HY male, of the fall season.

Note the green-edged 2nd alula feather (A2) that had not been molted giving us a clear molt limit. 

7 September brought in two more firsts for the season, a HY female Yellow-breasted Chat

and a HY Veery of unknown sex. 

We had both male and female Wilson's Warblers, a female on the 8th with a very drab cap

and a male with a partial black that will fill in as he ages. 

A Nashville Warbler arrived in the middle of September, a HY male

as did a Western PalmWarbler, note the very drab coloration of the face,  

and a species we rarely get on the island, a Purple Finch!  We were unable to sex this HY bird at this time. 

Purple finches don't have the streaking on the undertail coverts 

like House Finches do.

I had to take a number of days off away from the station so we probably missed a number of nice species but I thought my son's wedding was a bit more important! Happily we were greeted to a nice Lincoln's Sparrow on the 23rd

and our first Brown Creeper for the season on the 24th. 

Our first of hundreds of Yellow-rumped Warblers (subspecies Myrtle) arrived on the 29th, we banded six that day and shown is a HY male.

Other special birds of the day was a HY female Indigo Bunting, 

a HY Savannah Sparrow 

and an adult female Prairie Warbler. I know, I know it looks like a male and fools us every year but she is now aged as an A5Y meaning that she was born sometime  in 2008 or before. We first captured her in May of 2010 as an adult (ASY) with an egg and have captured her many times in years hence with a full brood patch. Just when you think you know a lot, birds throw you a wrench.

On the 30th we captured a very late and quite dull Yellow Warbler, possibly a western race,

Many thanks to all the volunteers who helped out at the station during August and September, it is much appreciated- Jo-Anna Ghadban, Ron Kielb, Gretchen Putonen, Rose Scavotto, Megan Nepshinsky, Catie Porro, Judith Bruce, Claire Revekant, and many others who helped out for a day or two. I am now posting all our sightings on ebird so for further information on numbers, etc visit ebird- Brewster Wing Island.