This is simply sabotage using disposable ships and sacrificeable seamen. The defense against that is not naval presence. In large we already have all the military equipment needed in forms of radar, underwater surveillance, satellites, and detection system in cables. Combined they will say exactly when the sabotage occurred, where and by which ship.
The problem is that of diplomacy. A major cause of the sabotage is to generate political support within Russia. When a ship is being arrested they will generate support around how evil west countries are boarding and stealing Russian ship and arresting innocent Russian citizens.
In term of countering this, the west has a problem of presenting evidence to the public since most of the surveillance is of military nature and thus secret. The historical/current method is to do it discreetly and simply send military ship to the offender and give a stern look that says that we know what you did. Then you send in the diplomats. We might see an escalation now since two ships has gotten boarded in very recent time.
The problem is that of diplomacy. A major cause of the sabotage is to generate political support within Russia. When a ship is being arrested they will generate support around how evil west countries are boarding and stealing Russian ship and arresting innocent Russian citizens.
In term of countering this, the west has a problem of presenting evidence to the public since most of the surveillance is of military nature and thus secret. The historical/current method is to do it discreetly and simply send military ship to the offender and give a stern look that says that we know what you did. Then you send in the diplomats. We might see an escalation now since two ships has gotten boarded in very recent time.