Thayer's Gull has been seen by:
| Birder | Location | Town | County | Date |
|---|---|---|---|---|
| Dylan Pedro | Coxes Ledge | Pelagic | Offshore | 20-Dec-2014 |
| Carlos Pedro | Coxes Ledge-Lady Frances | Pelagic | Offshore | 20-Dec-2014 |
| Cathy Gim | Cox's Ledge | Pelagic | Offshore | 20-Dec-2014 |
| Janaehesser | Offshore | Pelagic | Offshore | 20-Dec-2014 |
| Barbara Sherman | Lady Frances | Pelagic | Offshore | 20-Dec-2014 |
| Jan St.Jean | Pelagic | South Kingstown | Washington | 20-Dec-2014 |
| DAVID WALLIS | Pelagic | Offshore | 20-Dec-2014 |