Canadian Subs Protect Fisheries

By Sean M. Maloney

The primary Canadian enforcement agency for fisheries is the Department of Fisheries and Oceans (DFO). DFO maintains five armed offshore 70-meter patrol vessels, six 40-meter near shore patrol vessels, and 56 inshore vessels 20 meters long. DFO also operates a number of chartered patrol aircraft that sometimes are supplemented by MARCOM patrol aircraft. Given the 240,000 kilometers of coastline that must be covered, however, DFO is incapable of maintaining constant surveillance. At times, MARCOM can be called upon to assist DFO.

The use of Canada's maritime forces to support DFO is not new. The 1970 White Paper on Defense stated the two main priorities were to foster economic growth and to safeguard sovereignty and independence. Canadian forces were expected to participate in monitoring the EFZ. The 1994 Defense White Paper , the most recent expression of Canadian defense policy, includes "securing our borders against illegal activities" and "fisheries protection" as the third and fourth items under the first main priority, "Providing for the Defense of Canada and Canadian Sovereignty." The 1994 White Paper notes that Canadian policy will be to extend naval and fisheries operations beyond the EFZ to confront "predatory foreign fishing on Canada's continental shelf outside of our 200-mile exclusive fishing zone . . . while it is the Government's policy to avoid engaging in enforcement action beyond 200 miles unless absolutely necessary to protect a vital natural resource, the Canadian Forces must be capable of taking such action." This enforcement policy was carried out in April 1995 when a Canadian vessel fired on, boarded, and seized the Spanish trawler Estai . The Estai , though operating outside of the EFZ, was seen by undisclosed Canadian surveillance methods to be using a type of drag-net fishing equipment that is illegal under international law.

Maritime Command's publication Adjusting Course: A Naval Strategy for Canada , reconfirms that the first priority of Canadian national operations is "naval presence," which requires "naval forces capable of the full range of operations [that have] the capability required to assist in constabulary activities, normally the prime responsibility of other government departments . . . possession of naval forces capable of conducting operations from naval presence through sea control provides Canada with the ability to indicate convincingly its sovereign intentions to govern its claimed maritime areas of responsibility."

Legally, MARCOM can be asked to assist other government departments in what are called "Aid to the Civil Authority" operations. MARCOM is empowered to negotiate memoranda of understanding with other government departments as to the nature and extent of naval support that will be provided and operations are carried out as required. Operation Ambuscade marked the first time a Canadian submarine was used in resource-protection operations.

Planning Operation Ambuscade

Discussions between MARCOM and DFO in 1992 produced a formal request from DFO to National Defense for the use of a submarine in surveillance trials. The request was approved, and HMCS Ojibwa was made available in March 1993.

Then commanded by Lieutenant Commander Dean Marsaw, HMCS Ojibwa is a 90-meter, 2,410-ton (submerged) Oberon -class submarine built in Britain and launched in February 1964. Named after a native Canadian tribe, the Ojibwa is diesel-electric propelled. Her main armament consists of six torpedo tubes capable of firing Mark 48 wire-guided torpedoes. At the time of the operation, she was equipped with narrow- and broad-band sonar, low-light television (LLTV), 35mm photographic capability, VHS video capability, image intensification, and radar.

The "enemy forces" for Operation Ambuscade were U.S. scallop draggers who deliberately crossed the Hague Line into the Canadian zone and fished illegally. The scallop beds on the U.S. side of the Hague Line were unregulated and had become severely depleted by overfishing, making the Canadian side—regulated and thus prosperous—a lucrative target. The U.S. draggers would go "into Canadian water under cover of night or fog ... They gather approximately 5,000 pounds of scallop [and] return to the U.S. side of the Hague Line at sunrise to process the catch during the day. In a few days they can have a catch worth approximately $100,000...." Without adequate enforcement, DFO intelligence estimates indicated that poachers would stray deeper and deeper into Canadian waters "with the eventual possibility of ruining the Canadian scallop fisheries on the Georges Bank."

DFO's solution was to deter poachers. Commander Marsaw's orders were to conduct a patrol with a DFO officer on board. The Ojibwa's primary missions were to detect, track, identify, and initiate the apprehension of violators. Her secondary missions were to produce photographic, acoustic, and electronic information. Some of this would be used as evidence, and some for intelligence purposes. The priority was in gathering evidence. The friendly forces included a CH-124 Sea King helicopter equipped with forward-looking infrared radar (FLIR); a CP-140 Aurora long-range maritime patrol aircraft (also equipped with FLIR); additional DFO chartered surveillance aircraft, and DFO patrol vessels. U.S. Coast Guard vessels would participate on the U.S. side of the Hague Line. The DFO surveillance aircraft would proceed to the target area 24 hours before the Ojibwa departed to identify potential violators. If additional information was necessary after departure, the Aurora and Sea King would acquire it and transmit to the submarine using secure communications.

Fisheries Officer Bernard Sullivan accompanied the Ojibwa to provide legal eyewitness for when the Ojibwa's crew established the violator's geographic position and identity and to act as a professional witness in court if necessary. Sullivan would determine whether the violator was conducting illegal dragging activity or using illegal methods. Evidence gathered would be critical if any court cases developed from the operation. Only a law-enforcement officer could perform this task.

Marsaw was allowed several options to confirm the target's identity. He could track and observe by stealth and call in DFO aerial assets to track and board violators; he could track and observe, then pass the information on to DFO, who would arrange a U.S. Coast Guard intercept; or he could surface the Ojibwa and illuminate and identify the violator. There was, however, some concern that "this option risk[ed] retaliation by the target." No matter what option was selected, the Ojibwa was to maintain continuous contact with a violator.

Execution of the Operation

After a 20-hour transit from Halifax, Nova Scotia, the Ojibwa reached the operating area on 6 March 1993 and submerged. At 2010, the crew visually identified its first ship and attempted passive acoustic tracking. Marsaw initially wanted to keep the Ojibwa at least 4,000 yards away so that his tracking team could sort out the plot. Working a substantial group of fishing vessels was quite different from tracking ASW destroyers, and the crew had to take some time to adapt to the acoustical and other environmental operating conditions. This shake-down period was successful.

At 0815, the Ojibwa identified a Canadian fishing vessel. Marsaw intercepted it to develop his tracking team's proficiency. He also wanted to find out how close he would have to take the Ojibwa to get visual identification of a ship's name and nationality. The Ojibwa was able to get close enough to even identify the type of fishing equipment the target was carrying, while the sonar team was easily able to identify trawl noise and recovery sounds. Target vessels generally operated at speeds of four to six knots while fishing, making the tracking of individual ships easier.

This trial run completed, the Ojibwa moved closer to the Hague Line and intercepted a U.S. scallop dragger, which was two miles to the west on the U.S. side of the line, traveling at seven knots. Some fishing equipment can extend up to two miles underwater, so it is possible that ships in the U.S. zone can use their nets in the Canadian zone. By nightfall, the target moved right up to the line but did not cross it. Marsaw used this intercept to use the satellite navigation system to take navigational fixes. He also tested his backup locating systems (periscope bearing and radar ranging), so that he could be sure of the exact location if the dragger crossed into Canadian waters.

At 0237 hours on 8 March, the U.S. dragger crossed the Hague Line, and the Ojibwa intercepted her at 0400. The sonar operators informed the captain that the rake was being winched in, confirmed by a periscope shot. Unfortunately, the lowlight television (LLTV) had sustained damage, possibly during snorting, and the Loran C navigation station at Cape Race was out of service. With these systems in question, it was determined that enough evidence for court purposes was not available. Sullivan thought in retrospect that a DFO helicopter should have been called in at this point to apprehend the violator.

At around 1200, the crew visually identified another U.S. fishing vessel close to the Hague Line. Marsaw, however, wanted to replace the LLTV and move the Loran receiver from the radar mast to the communications mast. This ensured that the Ojibwa could use her radar while repairing the Loran receiver instead of losing both systems. The LLTV repairs were successful. Then the radar went down and it had to be repaired. The Ojibwa moved away from the target area into deeper water to conduct the repairs. Marsaw noted that Loran "was virtually useless, as even occasional mast wash-over caused chain slippage that would then require a SatNav fix or correction."

The repairs were completed at 2240, and the Ojibwa moved to intercept three U.S. vessels located within a mile of the Hague Line in the U.S. zone. The Ojibwa had to reestablish the identity of the three ships. The situation was further confused by two Canadian fishing vessels on the Canadian side of the line near the U.S. ships. By 0013 on 9 March, however, Marsaw and his crew identified two U.S. vessels holding position right on the Hague Line. The officer of the watch was instructed to take Loran fixes every 15 minutes and to check the bearing and range to the targets immediately afterwards to avoid the problems encountered previously. Marsaw then moved the Ojibwa two miles into the U.S. zone. His plan was to follow U.S. violators into the Canadian zone and be in a position to observe the sterns of the violators as the rakes were recovered. This also put the Ojibwa in a better tactical position, because she would be between the violator and the Hague Line and thus could respond to their movements.

The Canadian vessels inadvertently complicated the tracking problems. The fishing activity produced acoustic noise that sometimes masked similar sounds from the U.S. ships. Consequently, the Ojibwa moved away from the area to change her sonar arcs so that they paralleled the Hague Line. Marsaw noted that he "lacked faith" in the SatNav and Loran navigation systems and would have preferred GPS. The Ojibwa tracked one dragger, but it turned around before reaching the Line. The original target of 8 March was still hanging around the area, and a careful eye was kept on her. By this point. the sonar team had by this point set up a system to compare LOFAR-grams of the target vessels and identified this vessel from such a comparison.

On 10 March, the Ojibwa maintained sonar contact with two target vessels, including the 8 March violator. Both vessels moved parallel to the Hague Line and later strayed into the Canadian zone. Officer Sullivan got on the radio and informed the captains of the two U.S. ships that he was a Canadian DFO officer on board a Canadian submarine, that they had been tracked for two days, and that if they crossed again, they would be apprehended and charged. Canadian signals intelligence assets monitored the U.S. vessels' communications to gauge the reaction. Within hours, all U.S. fishing vessels operating in the area were informed by the two violators that a Canadian submarine was conducting a surveillance mission on the Georges Bank region and that perhaps they should not conduct poaching operations.

The next day, the Ojibwa surfaced for a photo near a Canadian fishing vessel. The captain was "very pleased to find DFO was using a submarine as a patrol platform," as an estimated $1 million of revenue was being lost each month, and the fish stocks were unable to replenish themselves if not regulated-which would in turn put him and other Canadian fishermen out of a job.


The lessons learned from Operation Ambuscade fall into two categories: operational and strategic. The primary problem encountered during the operation was the stringent navigational fix requirements necessary for a legal case. The solution, suggested by the Ojibwa's captain, is to have a GPS receiver attached to a mast so that an instantaneous fix can be taken once a target vessel is determined to have broken the line. Further upgrades to Canada's submarines after Operation Ambuscade include differential GPS and laser range-finding equipment. A target's position now can be established within 15 seconds.

Fisheries Officer Sullivan noted in his after-action report that there were problems in relaying area intelligence from DFO aircraft via MARCOM to the submarine because of a lack of interoperability in the communications system. DFO had daily reconnaissance flights over the operating area, but this information rarely was relayed to the Ojibwa . Intelligence had to flow from the aircraft, to DFO headquarters, to MARCOM headquarters, to a MARCOM communications site capable of communicating with the submarine. Operation Ambuscade was not treated as a joint operation. Perhaps Joint Task Force techniques should be established between law-enforcement departments and MARCOM for FishPat operations. This applies to both the format of the intelligence and the means used to transmit it.

On a lighter note, the DFO after action report noted that submarine accommodation apparently "is below standards for sea-going fishery officers and one could understand if there were simply no volunteers for future submarine trips." Sullivan was distressed by the facts that 80% of the 75-man crew smoked, the two heads were always busy, and the crew wore the same clothes all the time.

In its analysis, DFO compared the use of the submarine to its more conventional methods. Helicopters had some "covert capability" but had limited range and endurance and were weather dependent. Patrol vessels could stay on station, maneuver, and send out boarding parties—but they were not covert, and again, there were weather limitations. Though submarines had limitations—for example, their primary strength precluded them from apprehension—DFO concluded that "no other DFO platform has the ability to covertly track, locate, identify, and monitor vessels in fog." In addition, DFO did not have the capability to "obtain the distinctive acoustic signatures of fishing vessels." There were, however, concerns that "hostile fishermen could fire weapons at or attempt to ram a submarine" and that nets and other fishing gear complicated the problems of submerged movement in a high-density fishing area.

Submarines, therefore, are not completely effective enforcement instruments when operating alone. It is not surprising, then, that DFO recommended that a concept similar to a `sub-air barrier' be introduced along the Hague Line.

In the strategic realm, MARCOM and DFO held a press conference after the operation to describe what had occurred. The story was picked up by Canadian and U.S. media. In conjunction to the level of communication among the U.S. poachers during the operation, this made the fact the Canada operates submarines to support DFO in the area common knowledge, and provides a deterrent effect. The value of even one patrol was so high in that it was cost effective, and it provided excellent training in addition to the deterrent value afforded by twice-yearly irregular patrols. The number of U.S. violations of the Hague Line dropped from 33 in 1993, to 6 in 1994, to 1 in 1995.

Operation Ambuscade is a unique example of the supplementary uses of naval forces in general and of diesel submarines in particular. More importantly, the operation demonstrated that warfighting skills also apply in constabulary situations, and that alternative missions have important training value and contribute to the execution of peacetime national policy.

Dr. Maloney is a Canadian military historian who is currently working on an analysis of Canadian forces, joint operations, and crisis response.


Sean M. Maloney is the Historical Advisor to the Chief of the Land Staff and is an Associate Professor of History at Royal Military College of Canada. He served in Germany as the historian for 4 Canadian Mechanized Brigade, Canada’s Cold War NATO commitment in Europe. He is the author of nine books, including the controversial Canada and UN Peacekeeping: Cold War by Other Means and Learning to Love the Bomb: Canadian Nuclear Weapons and the Cold War. Dr. Maloney also has extensive research experience in the Balkans, Middle East, and particularly in Afghanistan where he has observed counterinsurgency operations in the field since 2003. He lives in Kingston, Ontario, Canada

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