Sightings:
- Slaty-backed Gull (3rd cycle type). Sitka County, Alaska. 02 September 2020.
- Black-legged Kittiwake (2nd cycle). Huron County, Ontario. 02 September 2020.
- Glaucous Gull (2nd cycle). Glynn County, Georgia. 04 September 2020.
- Continuing from June 2020.
- Franklin's Gull (2nd cycle). Prince County, Prince Edward Island. 04 September 2020.
- Continuing from July 2020.
- Black-headed Gull (adult). Lane County, Oregon. 06 September 2020.
- Little Gull (2 - 1st cycles). Cook County, Illinois. 07 September 2020.
- Little Gull (1st cycle). Inyo County, California. 09 September 2020.
- 2nd County Record.
- Little Gull (1st cycle). Jefferson County, Colorado. 11 September 2020.
- Sabine's Gull (juvenile). Pictou County, Nova Scotia. 15 September 2020.
- Sabine's Gull (7 - juveniles). Bay County, Michigan. 16 September 2020.
- Black-headed Gull (1st cycle). Norfolk County, Ontario. 16 September 2020.
- Slaty-backed Gull (2nd cycle). Mendocino County, California. 16 September 2020.
- Franklin's Gull (1st cycle). Juneau County, Alaska. 16 September 2020.
- Little Gull (adult). Johnson County, Iowa. 19 September 2020.
- Slaty-backed Gull (adult). Mississauga, Ontario. 21 September 2020.
- 1st September Record locally, and for the entire Great Lakes region.
- Laughing Gull (2nd cycle). Maricopa County, Arizona. 20 September 2020.
- Great Black-backed Gull (adult type). Keith County, Nebraska. 20 September 2020.
- Lesser Black-backed Gull (2nd cycle). Pierce County, Washington. 24 September 2020.
- Lesser Black-backed Gull (adult). San Miguel County, Colorado. 24 September 2020.
- 1st County Record.
- Lesser Black-backed Gull (adult). Yavapai County, Arizona. 24 September 2020.
- 1st County Record.
- Laughing Gull (adult). Douglas County, Wisconsin. 26 September 2020.
- Red-legged Kittiwake (2nd cycle type). Nanaimo District, British Columbia. 27 September 2020.