Prothero Boat Co.
Seattle WA
The Prothero Boat Company was started in 1870 and closed in 1959. Between 1929 and 1942, the Protheros were joined by Ernest McDonald and the name was changed to Prothero & McDonald Boat Co. The shipyard was on the west side of Lake Union, at 2046 Westlake Drive W., where the Electric Boat Company is today.
| O/N | Name | Customer | Type | GT | LOA | Built | Notes | |
| 229826 | Mickey | trawler | 9 | 33 | 1930 | |||
| 231002 | Allure | recreational | 20 | 42 | 1931 | later Santa Guadalupe, Allure | ||
| 231719 | Sonsie | recreational | 14 | 37 | 1932 | NLD | ||
| 233158 | Trixter | recreational | 14 | 33 | 1934 | |||
| Q-48 | US Army | launch | 1942 | |||||
| Q-51 | US Army | launch | 1942 | |||||
| 274565 | ST-379 | US Army | tugboat | 23 | 52 | June 1943 | later CivAir 21, Skookum | |
| ST-380 | US Army | tugboat | 52 | July 1943 | ||||
| 269022 | ST-388 | US Army | tugboat | 16 | 52 | July 1943 | later Arlington | |
| 246044 | Ursus | trawler | 12 | 32 | 1944 | NLD | ||
| 246195 | Roberta | Irving Stamnes | freighter | 56 | 58 | 1944 | NLD | |
| 248401 | Alrita | trawler | 72 | 63 | 1945 | NLD | ||
| 248589 | Coral Sea | trawler | 35 | 48 | 1945 | later Ginny Lee | ||
| 250226 | Vigorous | trawler | 56 | 58 | 1946 | NLD | ||
| 253755 | Susan H | Halvorson Towing | tugboat | 39 | 55 | 1947 | later Connie, Princess, Kinnickinnic, Yeomalt, Susan H | |
| 261837 | P & T Pioneer | Pope & Talbot | tugboat | 59 | 60 | 1951 | later Pioneer, Pacific Pioneer | |
| 265385 | Sierra Madre | Mick Vodjokovich | trawler | 52 | 50 | 1953 | NLD | |
| 271314 | Alcyone | recreational | 29 | 57 | 1956 | |||
| 271816 | Peniel | recreational | 14 | 40 | 1956 | NLD | ||
| 273547 | Lakesider | Lakeside Gravel | recreational | 12 | 34 | 1957 | later Heron | |
| 276632 | Seven Seas | trawler | 73 | 58 | 1958 | later Sierra Seas, St. Francis |