[mou] Slaty-backed Gull at Superior, WI landfill

[Peder Svingen]

Approximately three hours of watching gulls from outside the fence at  
the Superior Landfill today (28 December 2007) revealed the following  
larids:

Herring Gull -- 950 (counted by groups of 50 in flight; this was the  
highest total out of about 15 counts);
Thayer's Gull -- 4 (one first-cycle, one second-cycle, 2 adults);
Glaucous Gull -- 12 (5 first-cycle, 2 second-cycle, 2 third-cycle, 3  
adults);
Great Black-backed Gull -- one first-cycle.

Prior to my arrival, Fr. Tom Margevicius saw a first-cycle Iceland  
Gull. The Slaty-backed Gull (see below) was not refound.

Fr. Tom also mentioned that he found a Northern Hawk Owl yesterday  
along the Admiral Road (St. Louis County Road 788), about a mile north  
of the Sax Road (county road 28) in the Sax-Zim Bog.
--
Peder H. Svingen
Duluth, MN

On Dec 21, 2007, at 5:37 PM, Karl Bardon wrote:

> I watched gulls at the Superior, Wisconsin landfill
> today from approximately 10:00-15:00 and saw the
> following:
>
> At least 680 Herring Gulls, eight Glaucous Gulls (5
> first-cycle, 1 third-cycle, and 2 adults), seven
> Thayer’s Gulls (2 first-cycle, 2 second-cycle, 3
> adults), and three Iceland Gulls (1 first-cycle, 1
> third-cycle, and 1 adult). The number of birds
> (especially Herring Gulls) is likely much greater than
> posted, since there is a constant influx and outflux
> of gulls, and since I only counted the number of each
> age seen at one time, or new individuals that I could
> recognize based on plumage differences. The majority
> of gulls were identified in flight since the landfill
> is closed to the public and viewing can only be done
> from outside the fence.
>
> Also seen and photographed was an adult Slaty-backed
> Gull. The latter was studied off and on for several
> hours both perched and in flight, and showed the
> following: size of large Herring Gull with overall
> bulky structure and large bill, yellow irides, pink
> legs, heavy head streaking that formed a distinct bib,
> broad white tertial crescent, slate gray mantle, and a
> “string of pearls” effect formed by white subapical
> tongue tips on primaries 6-8 (dorsally and ventrally).
> When the bird flew directly overhead, I was able to
> see a large white subapical mirror on primary 10 (the
> outermost), a moderate sized white window on primary
> 9, and subapical white tongue tips on primaries 6-8.
> When the bird was perched with the underside of
> primary 10 showing, this feather appeared medium gray
> except a large white subapical mirror, a narrow
> darksubterminal bar, small white apical spot, and a
> distinctly dark, narrow outer web.
>
> Karl Bardon
>