Monday, February 22, 2010

2010 IOS Gull Frolic

Gulls, gulls, gulls and more gulls.  That's what this past Sat (Feb 20th) was about.  It was the Illinois Ornithological Society's (IOS) annual Gull Frolic field trip.  This trip has been going on for quite a number of years and has changed over the years to become almost a one day Gull festival rather than a just field trip.  Complete with food, drinks, tons of people and even a speaker for the day, this is definitely one of the best Gull-watching events in the country. 

This year, the festivities had record attendance.  Mostly of people, but thousands of gulls also received the memo about the day and arrived right on schedule.   
There was no way to count the total number of gulls that covered the harbor and left little room for the ice. Estimates ranged anywhere from 6 to 10,000 birds.  
This year, gulls of seven different species were in attendance.  As always, Herring Gull was present in the highest numbers with Ring-billed being a close two.  It was difficult to say who was in third place though. Thayer's Gulls probably took that spot due to the 8-12 individuals that were flying around.  
Third place was Glaucous Gull at at least 5-7 individuals floating around the harbor. Iceland Gull was a close fourth though with at least 4 birds present.  Three Lesser Black-backed Gulls hovered around with at least two giving excellent looks.  Great Black-backed Gulls weren't quite as cooperative. The only individuals present coming only as close as the breakwater. 

Chumming was the order of the day.  Don't know what Chumming is?  That's why I'm here. 
Chumming is essentially baiting the birds to get them to come in closer and create a flock that helps draw in other birds.  The word comes from the Virginia Algonquin Indians from a word that they used for the practice of baiting fish.  It is done most effectively during pelagic trips where Popcorn, fish scraps, fish oil, blood and anything else edible is tossed into the wake of the boat where the ever hungry gulls come to get it. The feeding flock eventually attracts other opportunistic scavengers such as Petrels, Shearwaters and Albatross.  In this case, since we were inland and had no seabirds to attract, the bread we threw out served only to draw the birds closer for better photo ops and ID looks at birds such as this winter adult American Herring Gull: 

Iceland Gull was a favorite of the day, though no L.g. glaucoides subspecies could be identified out of the flock.  All of the individuals seen were the Larus glaucoides kumlien's subspecies like this 1st cycle "Kumlien's" Iceland Gull:

Glaucous Gull was easily one of the larger gulls to attend. This bird is easily distinguished from the Iceland above by it's very pale, bleached, almost white feathers, pinkish bill with a black tip and massive size.  These birds are almost as big as Great Black-backed Gulls, just to give you an idea of how big they are. 

This guy was also a bit of a bully: 

This Lesser Black-backed Gull was highly cooperative and gave me a chance to get some decent shots for once.  Lesser Black-backed is a relatively easy gull to identify. The darker back, streaked head (though lightly on this bird) Herring Gull sized bill and distinctly yellow legs make this gull stand out quite well in a flock: 

Thayer's Gulls are not quite as obvious at first.  The adults of this species look almost exactly like adult Herring Gulls but with a few differences.  The bird below is a classic adult Thayer's Gull.  
Lack of black on the primaries, heavily streaked head, smaller bill and head, almost "daintier" structure, dark eye, etc. 

As I noted above, Thayer's Gulls can be quite tricky to ID.  Here is one such example.  
The bird below is a Thayer's Gull (Larus thayerii).  In naming some of the field marks of the bird above, I named the dark eye as one of the primary ones.  The dark eye can be quite useful in picking out adult Thayer's Gulls out of a flock. However, the bird below is proof that this ID mark is not always reliable. 
This Thayer's Gull has a yellow eye.  Every other ID mark fits, except the eye.  Although, the bill is slightly more yellowish as well. Also note that the inner webs of the primaries are darker black than you'd normally expect and there is little streaking on the head. Sometimes makes me wonder if these birds are actually hybrids with Herring Gull or not.  At any rate, the current accepted ID for these birds is and remains Thayer's. 

Anywho, I will be dealing with more details of Gull identification in a later post.   My next post will be my favorite photos from the day and then my Gull ID post so watch for that soon!

The Gull frolic was an awesome experience and if you haven't been, I would highly recommend attending at least once, if not multiple times.  It's always on the same weekend every year so mark your calendars!!
Many thanks go out to the members of the IOS Gull Frolic committee who went to great lengths to organize this year's festivities and entice Gull expert Alvaro Jaramillo to come all the way from his home in Half Moon Bay, California to the icy Midwest to give his excellent presentation on Slaty-backed Gull ID (which I will partly touch on in my gull ID post and in the next post as well.)

So til next time,
Happy Birding!


Dawn Fine said...

Great post..I cant even begin to ID gulls like you do...maybe someday!

Andrea said...

Looks like it was a lot of fun! Great post and fantastic birds. :D

Jochen said...

About the gull on your last pic:

As far as I know, Sibley notes in his guide(s) that a small percentage of winter Herring Gulls in the East show a wing tip pattern similar to Thayers. To me, the gull looks suspiciously like a Herring, although of course the wing tip pattern says Thayers.
I have seen one of these birds in Michigan in winter and have tentatively called it a Herring (so Thayer's remains off my life list).
In Europe, we have a comparable situation: in harsh winters, a few of the Herring Gulls (different species though) we see in central Europe show a very limited amount of black on their wing tips and these birds presumably are from the northern-most parts of their European breeding range.

Well, as the other Thayer's in your post is a definite Thayer's, it won't matter as much to you as for me (lifer pending), but you might be interrested in investigating further...

Cheers, happy birding trails

Anonymous said...

Yes, the last photo in this post is most definitely of an adult (American) Herring Gull. The facial expression is entirely different from a Thayer's and the structure is not supportive of a Thayer's ID.

troutbirder said...

Wow that's a lot of gulls. I'm a second year but mature birder who has a lot to learn in general about birding and in particular about gulls. Am familiar with Sax Zim area as one of my favorite fishing lakes is near Melrude.

Anonymous said...

Thayerthz arethz impothzziblze tewthz identhurfeethzz