25 March 2011

Franklin's & Black-legged Kittiwake Day!

The end of March is usually the end of "winter gulling" for me and so I made one last effort today to get out and find a white-winger. Steve Spitzer was having a good week at Loyola Park with Thayer's, Kumlien's and Glaucous Gulls and so I thought I would make my way up north. As I was driving to Loyola, I read a post by Kanae Harabayashi reporting a Black-legged Kittiwake at Montrose Harbor in Chicago. I stopped at Montrose and found the BLKI resting on a dock slip after about 10 minutes of searching. Rob Curtis and I approached the bird from a good angle and fired off some shots:

1st cycle Black-legged Kittiwake. Montrose Harbor. Chicago, IL; 25 MAR 2011.
Black-legged Kittiwake is a rare spring migrant in Illinois and so I have my doubts about this bird being a spring transient. It very well may be one of the several Black-legged Kittiwakes that presumably wintered on lower Lake Michigan this winter. The last such BLKI was seen was on 9 FEB 2011 at Montrose. To read more about this winter's great number of BLKIs, click here: http://anythinglarus.blogspot.com/2011/01/black-legged-kittiwakes-on-southern.html

After scoring the kittiwake, I made the 10 minute drive up to Loyola with Rob. This was my first time birding this location and so it was nice to have someone with me who knew the site. We searched for Steve's white-wingers, and despite getting the Ring-billeds up in the air for some bread, not a single Thayer's, Kumlien's or Glaucous Gull was to be found. We walked north along the beach where I soon spotted a hooded gull. I spent a minute or so trying to decide whether it was a Franklin's or Laughing Gull. We inched up a bit and settled for a Franklin's (Laughing Gull is a rarer gull in Illinois):

Near-adult Franklin's (2nd PA?) with adult Ring-billed. Loyola Park. Chicago, IL; 25 MAR 2011.
 The Franklin's came in for bread a couple of times and was even successful at picking some off the surface of the water in between the lager, ravenous Ring-billeds. As always, the rarer gulls come in briefly and make an abrupt exit.

The pink suffusion on the underparts is very common in Franklin's Gull. One of the first things that I noticed as I made the ID on this individual is the contrasting pink tones to the underparts of the body. I aged this bird as a 2nd cycle, although I do admit that I'm regularly rethinking Franklin's molt strategy - it's not an easy one as this species does all sorts of interesting  things with its two "complete" annual molts.

Franklin's commonly suspends its primary molt. Many times the prealternate molt is NOT complete and several outer primaries are retained for an entire season. To my eyes, it seems that the inner and mid-primaries (P1-P6) have just been renewed. The result is an "incomplete" prealternate molt as the outer primaries (P7-P10) are retained feathers from the previous molt. The big question is whether those outer primaries are retained juvenal feathers or retained 1st alternate. My guess is that they're retained 1st alternate feathers. That would imply that the new inner and mid-primaries are 2nd alternate.

The alternative would be a 1st alternate bird with retained juvenal outer primaries. I think the other features on this bird - all-white tail, extent of black on the hood, and lack of extensive markings on primary coverts - help support 2nd cycle. One thing that is troubling me is the lack of white tongues on any of the outer primaries and the abraded white tips to these same feathers. My only explanation for this is that the first prealternate molt was incomplete, leaving 3-4 old primaries that have by now become worn at the tips. I would approximate the age of this bird to be 18-20 months.