- Slaty-backed Gull (adult). San Mateo County, California. 01 March 2018.
- Mew Gull (adult). Kings County, New York. 02 March 2018.
- Thayer's Gull (adult). Yarmouth County, Nova Scotia. 03 March 2018.
- Continuing from previous month.
- Black-legged Kittiwake (1st cycle). Douglas County, Kansas. 04 March 2018.
- Continuing from previous month.
- Laughing Gull (1st cycle). Mohave County, Arizona. 04 March 2018.
- Continuing from January 2018.
- Black-tailed Gull (adult). Del Norte County, California. 05 March 2018.
- Continuing from previous month.
- Kumlien's Gull (1st cycle). Harrison County, Mississippi. 07 March 2018.
- Lesser Black-backed Gull (adult). San Diego County, California. 08 March 2018.
- California Gull (adult). Cuyahoga County, Ohio. 08 March 2018.
- Slaty-backed Gull (3rd cycle). Pierce County, Washington. 09 March 2018.
- Mew Gull (adult). Plymouth County, Massachusetts. 09 March 2018.
- Mew Gull (adult). Lancaster County, Nebraska. 11 March 2018.
- Mew Gull (adult). Mohave County, Arizona. 11 March 2018.
- Black-legged Kittiwake (1st cycle). Chatham County, Georgia. 14 March 2018.
- Black-legged Kittiwake (1st cycle). Plaquemines County, Louisiana. 16 March 2018.
- Slaty-backed Gull (2nd cycle). Santa Clara County, California. 17 March 2018.
- Black-headed Gull (adult). Baltimore County, Maryland. 17 March 2018.
- Slaty-backed Gull (2nd cycle). Monterey County, California. 18 March 2018.
- Sabine's Gull (adult). Los Angeles County, California. 23 March 2018.
- Sabine's Gull (adult). Marion County, Oregon. 25 March 2018.
- Kamchatka Gull (adult). Digby County, Nova Scotia. 25 March 2018.
- Continuing from previous month.
- Great Black-backed Gull (adult). Mobile County, Alabama. 28 March 2018.
- Franklin's Gull (1st cycle). Union County, Pennsylvania. 31 March 2018.
Miscellaneous Notes
- An assembly of Heermann's Gulls (~100) appear to be preparing for nesting in Seaside, California.