Actions undertaken by the northern fleets were sporadic and depended on the whether there were pressing threats to the frontier. For example, there were significant actions from 20 B.C. to 10 A.D. under Augustus when he was trying to establish provinces in the Balkans, but peacetime idled the navy from 15-69 A.D. After 85 A.D, the Dacian Wars occupied the fleets of the lower Danube for twenty years.
There are no real descriptions of the northern fleets in battle, only their support of the efforts of the army. Lack of historical detail and the fact that the indigenous people lacked navies, leads one to believe there few independent actions that one could label noteworthy.