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August 2010


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Dennis and Barbara Martin <[log in to unmask]>
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Dennis and Barbara Martin <[log in to unmask]>
Sun, 8 Aug 2010 00:29:30 -0600
text/plain (148 lines)
Thanks to Peder for getting the earlier message out.  Hopefully the advance 
notice of our message tonight will allow some of you the opportunity to try 
and look for this bird.  The best time is not until midday as you will be 
looking generally east and the sun will be a problem early in the day.  You 
will need a scope.

We are well aware how hard it is to differentiate subadult Franklin's and 
Laughing gulls.  In fact it may not be possible without a better (and closer 
look) than we had today.  Nevertheless, we believe that this is probably a 
Laughing Gull because of several factors.  All these points refer to a 
standing and preening gull.  We were never able to see it in flight.  The 
dark gray back clearly points to one of these two species.  Black-headed 
Gull, while having a darker head, is eliminated because of its' lighter back 

Some of the coverts and tertials appeard to have substantial remnants of 
juvenile or first winter plumage.  This generally brown plumage is present 
in this area in a first winter Franklin's Gull or a first summer Laughing 
Gull according to Olson and Larsson (Gulls of North America, Europe, and 
Asia.)  This is August so a first winter plumage would have to be really 
severely retarded by nearly six months or so and we don't believe that this 
is realistic.  We should add that when we first saw this bird we suspected 
Laughing Gull because we have never seen a Franklin's that looked like this 
anywhere near this time of year.  It just didn't look right for a Franklin's 
at all.

The tips of the tertials appeared to display no white edging.  Franklin's 
Gulls tend to show some very minimal white as early as first winter and in 
first summer they show extensive white edging to the tertials.  Laughing 
Gulls tend to not show white edging to the tertials until the second winter 
phase.  In first summer and first winter white edging is very minimal.  Even 
accounting for the distance that we were viewing this bird, we believe that 
we would have been able to see white edging if it was more than very 
minimal.  By the way we were viewing this bird with the bright sun behind us 
(occasionally behind light clouds) and with enough of a breeze that we 
experienced no heat waves through our 50 power scopes.

The folded wing tips did not show any white spotting.  Franklin's Gulls 
shows white spotting (from the wing tips) as early as first summer while 
Laughing Gull does not show much white spotting till the adult plumage.  One 
of us got a good long look at the top of a raised wing (while the bird was 
preening) and no white was evident between the black tips and the dark gray 
top area of the wing.  David Sibley in his guide (the only one we had with 
us at the time) shows some white in this raised wing area as early as first 
summer for Franklin's and basically never in Laughing Gull.

From looking at the Sibley Guide today, and Olson and Larsson tonight, it 
appears that the bottom of the wing is somewhat diagnostic in 
differentiating these two species.  As I said we were unable to see this 
bird in flight.  One of us got a short look at the bottom of one wing while 
it was preeening and felt that the wing showed a lot of darkness as compared 
to what you would see in a Franklin's Gull.  Franklin's tend to be very 
white in the underwing area except for the black tip while Laughing tends to 
show more extensive dark areas.  Clearly we probably did not get a good 
enough look at this underwing area.

Laughing Gull has a longer bill than a Franklin's Gull.  We were not able to 
tell anything with the distant study we had of this bird.  With no 
comparison the length seemed to be of no help to us in figuring this out.

The bird did not have the typical dark head of these species in adult 
plumage but it did show extensive shading of black throughout the head. 
Generally summer subadult Franklin's have their black primarily on the back 
half of the head.  Laughing tends to have black in more extensive areas of 
the head although not the deep black of adults.  We definitely felt this 
favored Laughing Gull.

Similar to this is the fact that Franklin's Gull from first winter on shows 
a very clean white neck, chest, and side of chest while Laughing Gull shows 
some smudging in these areas.  Depending on which book you look at you get a 
different idea of how much smudging is on the Laughing Gull but both books 
show this very clearly until they reach adult plumage.  The bird today had 
smudging on the neck and the sides of the chest.  It didn't appear to have 
much in the center of the chest but it was very clearly on the sides and 

We should add that we looked at this bird for well over and hour and a half, 
during which time the bird did little except walk around along the edge of 
one of the islands that the gulls were on.  When we looked away for a short 
time one of the numerous eagles or the locally persistent Peregrine Falcon 
flew low over the gulls and they shuffled their position.  We were unable to 
refind the gull after that point.  We do not believe that it left the area. 
It probably just shuffled to the back of the flock or the back of the island 
and we were blocked from seeing it.  In future days it may take more than 
one stop at this place to find it.

Something to consider is what species is more likely in this area at this 
time of year.  We believe that the closest nesting area for Franklin's Gull 
would be Agassiz NWR although nonbreeding birds are seen further south off 
and on in western MN.  We haven't looked this up but suspect based on our 
experience that nearly all of these sightings of these nonbreeding birds are 
in the northwestern quarter of MN this time of year.  Laughing Gulls are 
regularly reported in Missouri and we think occasionally in southern Iowa 
along the Mississippi River.  We have not researched this so somebody may 
want to correct or expand on this info.  So Houston County is kind of in the 
middle between these two regions.  Remember that last summer Chris Wood 
documented an adult Laughing Gull from this area of MN about this same time.

More research is to be done.  Hopefully somebody will find this bird and be 
able to digiscope it.  We took a couple of very long shots today but 
remember that we use film so don't expect the photos to be of much help.  A 
good digiscoper would have done well today.  And a last note.  We have very 
little experience with Laughing Gull and very extensive experience with 
Franklin's Gull.  This whole thing started because this bird did not look 
right for Franklin's Gull.

Dennis and Barbara Martin
Shorewood, MN
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----- Original Message ----- 
From: "Peder Svingen" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Saturday, August 07, 2010 6:54 PM
Subject: [mou-net] possible Laughing Gull, Houston County

> Dennis Martin just called and asked me to post his sighting of a possible 
> first-cycle Laughing Gull in Houston County. The bird is sitting on an 
> island in the river (the same island where an avocet was seen last week) 
> about a quarter mile east of the wooden viewing platform along highway 26, 
> approximately 4 miles south of Brownsville. Due to the distance he has 
> been unable to evaluate bill size or shape, and he has not seen the bird 
> in flight. The bird is amongst a flock of several hundred Ring-billed 
> Gulls and looks smaller than all of the adjacent Ring-billeds. Dennis 
> stated that the folded primaries are solidly black and that its back is 
> clearly darker gray than the Ring-billeds, with brownish tertials. 
> Although the bird has extended its wings while preening, he has not been 
> able to see the ventral surface of its remiges and he has not seen its 
> tail pattern.
> Dennis is keenly aware of how difficult it can be to distinguish 
> Franklin's and Laughing gulls and hopes that other birders are able to 
> refind this bird. In addition to Gulls of the Americas (Howell and Dunn) 
> and other books specifically addressing gull identification, birders may 
> wish to consult Kenn Kaufman's Advanced Birding field guide for further 
> guidance.
> Thanks to Dennis for his timely report.
> --
> Peder H. Svingen
> Duluth, MN 

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