Oliver,

In May 1917, all British trawlers still under civilian control were taken into the Fishery Reserve. This made them HM vessels of a sort, though they continued to fish with their same crews for their owners as before. A portion were to be defensively armed though. Of course, such a defensively-armed trawler could easily have been described as a “Bewacher.”

Will add this incident into the database with Strathearn listed as "trawler" not a "navy trawler"

Joe -- thaks for the link, saves me from having to dig out the information on this vessel.

Best wishes,
Michael