30 June 2021

Short-billed Gull - Larus brachyrhynchus

Big news! The Mew Gulls have been split into two species, Larus canus and Larus brachyrhynchus. The proposal, put forth by Pamela C. Rasmussen back in November of 2020, can be found here. Data that bolstered the split comes from a combination of genetic, morphological and vocal differences, in addition to well-established geographic isolation of brachyrhynchus

In the 62nd Supplement to the AOS Check-list of North American Birds, Short-billed Gull is the name "resurrected" for the American taxon, Larus brachyrhynchus (formerly known as Mew Gull to North American observers).

The canus group now includes Old World taxa, Common Gull (nominate L.c. canus) and Kamchatka Gull (L.c. kamtschatschensis). Nominate is rare to Newfoundland, Nova Scotia and Quebec, and casual south of here to NY. Beside being very rare in Alaska, Kamchatka is casual, but increasing, in the Northeast from Atlantic Canada, down to New England. The supplement makes no mention of the less known race, heinei, or Russian Common Gull (L.c heinei), as it is known in Europe and Asia. There are no known reports of heinei in North America, possibly due to an observer bias. Field identification of all four forms -- with helpful notes on vocalizations -- can be found in Adriaens & Gibbins (2016).

The addition of Short-billed Gull puts the number of gull species on the ABA Checklist at 31. 


1st cycle Short-billed Gull (Larus brachyrhynchus) with adult California Gull.
Washington. January. photo: Amar Ayyash.



1st cycle Common Gull (Larus c. canus) with 1st cycle Ring-billed Gull.
New York. December. photo: Andrew Baksh.



1st cycle Kamchatka Gull (Larus c. kamtschatschensis) with adult Vega Gull.
Japan. December. photo: Amar Ayyash

01 June 2021

Monthly Notables May 2021

Sightings:

  • Little Gull (1st cycle). Keweenaw County, Michigan. 01 May 2021.
  • California Gull (adult). Johnson County, Iowa. 02 May 2021.
  • Thayer's Gull (1st cycle). Lewis and Clark County, Montana. 03 May 2021.
  • Lesser Black-backed Gull (2nd cycle). San Francisco County, California. 05 May 2021.
  • Lesser Black-backed Gull (3rd cycle). Grays Harbor County, Washington. 06 May 2021.
  • Kumlien's Gull (1st cycle). Cook County, Illinois. 08 May 2021.
  • Franklin's Gull (adult). Norfolk County, Ontario. 08 May 2021.
  • Lesser Black-backed Gull (adult type). Central Kootenay District, B.C. 08 May 2021.
  • Little Gull (1st cycle). Warren County, Ohio. 10 May 2021.
  • Slaty-backed Gull (2nd cycle). Alameda County, California. 11 May 2021.
  • Franklin's Gull (3; 10 adults). Lincoln County, Oregon. 11 May 2021.
    • Likely a high count for coastal Oregon.
  • Glaucous Gull (1st cycle). Marin County, California. 11 May 2021.
  • Kumlien's Gull (1st cycle). Bucks County, Pennsylvania. 11 May 2021.
  • Heermann's Gull (3rd cycle). Virginia Beach County, Virginia. 11 May 2021.*
    • 2nd State Record. P1 dropped and thus the 3rd prebasic molt has commenced.
  • Laughing Gull (adult). Valdez-Cordova County, Alaska. 12 May 2021.
    • Apparent 7th State Record.
  • Little Gull (1st cycle). Santa Cruz County, California. 13 May 2021.
  • Black-legged Kittiwake (1st cycle). Durham County, Ontario. 13 May 2021.
  • Franklin's Gull (1st cycle). Dare County, North Carolina. 15 May 2021.
  • Ivory Gull (adult). Nome County, Alaska. 20 May 2021.
  • Little Gull (adult). Kings County, California. 22 May 2021.
  • Black-headed Gull (adult). Nome County, Alaska. 24 May 2021.
  • Franklin's Gull (adult). Anchorage County, Alaska. 25 May 2021.
  • Heermann's Gull (3rd cycle). Bristol County, Massachusetts. 27 May 2021. 
    • 1ST STATE RECORD. 3rd generation p1 growing in, p2-p3 dropped.
  • Heermann's Gull (3rd cycle). Newport County, Rhode Island. 27 May 2021.
    • 1ST STATE RECORD. Same individual from VA & MA.
  • Thayer's Gull (1st cycle). San Diego County, California. 28 May 2021.
  • Franklin's Gull (adult). Skagway-Hoonah-Angoon County, Alaska. 29 May 2021.
    • 1st for Gustavus, Alaska.
  • Ivory Gull (2nd cycle). Nome County, Alaska. 29 May 2021.
  • Herrmann's Gull (3rd cycle). Cape May County, New Jersey. 30 May 2021.
    • 1ST STATE RECORD. Same individual from VA, MA, RI. 
    • 3rd generation p1 growing in, p2-p3 dropped.
  • Black-headed Gull (2nd cycle). Cape May County, New Jersey. 30 May 2021.
    • Continuing.

Notes:

* The Heermann's Gull that excited several Northeast Atlantic states this month yielded three 1st state records (MA, RI, NJ) and a 2nd state record (VA) all within 20 days. It is believed this is the same Heermann's first found in Palm Beach County, Florida as a juvenile in August 2019. Age, molt and plumage patterns work out perfectly, as well as its sporadic wanderings. This bird also produced a 1st state record in Georgia back in February-March of 2021. It was last seen in Volusia County, Florida on 23 March 2021 before being spotted in Virginia Beach this month. It's obvious this bird has a faulty compass and is likely to turn up anywhere!


May 2021 Quiz

 

Wisconsin. July. 

Age: Gull identification and aging go hand in hand, with the former often dependent on the latter. As we work on identifying a gull, we should be keen to place it in an age group based on plumage patterns. Age and plumage are discussed below.

Identification: The gray-backed birds on the left and right have slender pinkish-yellow bills with defined black rings. The spotted neck markings and finer streaking on the crown, as well darkish eyes safely relegate them to Ring-billed Gull (2nd cycles). Note the 1st generation outer primaries that are holding on (brown), which is expected at this time of year, with new incoming 2nd generation primaries growing in (black with white apical spots). These one-year old Ring-billeds are starting to show yellowish legs, but it is difficult to appreciate this field mark due to both lighting and a slight delay in bare part color maturation.  

The individual in the center is a black-backed species. It's relatively compact, but the solid dark brown upperparts, slender vent region behind the legs and parallel-edged dark bill all look great for Lesser Black-backed Gull. By direct comparison to the Ring-billeds, it is a notably small Lesser, likely a fm type. This too is a 2nd cycle, retaining old 1st generation primaries while molting the inner primaries.

It should be noted that these birds are undergoing their 2nd complete molt (known as the 2nd prebasic molt). Therefore, they are now 2nd cycle gulls.