If they were Atlantics they may have been fish farm escapees. Although the Lamprey river was one of the focal points of Coho stocking during the 1970's I believe that the run was declared *extinct* long ago. The only Pacific salmon reports I've heard of in the last 20 years have been either fish farm escapees, or migrants out of the Great Lakes (the latter being relatively common in Nova Scotia). Sea run Browns and Atlantics look very similar. The best way to tell the difference is to look for the pronounced *V* in the tail of an Atlantic. Once you key in on this trait it is very easy to differentiate Salmon from brown trout at any size.
Regards,
Eric