One of the major players is Suncor in Fort McMurray. In recent years it has built up a fleet of its own in addition to several boats it has chartered in, including conventional tugs and multicats to support work barges and cutter suction dredges.
The tugs are generally under 15 gross tons, and thus are only registered by official number, despite carrying a name.
Quebec City based Groupe Ocean has been providing various of the craft some chartered and some for purchase, which can be transported to Alberta over the road and assembled on site.
The latest appears to be a twin screw icebreaking tug/ workboat, built at
I always welcome corrections from readers, so wish to thank those who pointed out some mistakes in the orginal post:
Revision: In fact Suncor 11 was built by Industrie Océan at Ile-aux-Coudres, QC. It was transported to the Quebec City facility for adjustments prior to beginning its long road trip. It is powered by a pair of 500 bhp Volvo Penta engines.