
Inter-agency Patrols
- Largest system of fresh water in the world
- 20% of the world's supply of fresh surface water
- 11 million Ontario residents (30% of all Canada)
- 30 million USA residents (10% of all USA)
- Major ecological, recreational, commercial and economic benefits for Ontario
Recreation and development demands on these resources are extremely high.
Great Lakes Conservation Officer's primary duties are split between commercial and sport fishing enforcement.
Lake Ontario
The Lake Ontario Enforcement Unit's jurisdiction crosses three MNR administrative Districts, Kemptville, Peterborough and Aurora and enters into a fourth; Guelph.
- 1,146 km shoreline (50% in Ontario)
- Population over 2.8 million people
- Ontario portion of the lake is 10,000 square km
- Maximum depth of 802ft. / average depth 286 ft.
- Four conservation officers, one Intelligence and Investigations Officer and one Enforcement Manager are responsible for the enforcement of sport fishing, commercial fishing, wholesale and the live food fish markets in the GTA.
- 175 Ontario Commercial Fishing Licences (harvest primarily with gill, trap and hoop nets)

Lake Erie
- 900 km of shoreline
- 13,500 sq km of surface area
- 4 Conservation Officers,
- I Enforcement Manager
- 1 Intelligence and Investigations Officer
- 183 gill /trawl and trap net licences
- 17 hoop net licences in Long Point Bay
Upper Great Lakes (Lake Superior and Lake Huron)
The Upper Great Lakes Enforcement Unit is the largest geographic enforcement unit within the province. It includes the main basin of Lake Huron, Georgian Bay, North Channel, St. Marys River and Lake Superior. The Unit is divided into six patrol areas with officers working from; Thunder Bay, Sault Ste. Marie, Espanola, Parry Sound, Midland and Owen Sound and an Enforcement Manager based out of the Owen Sound office.

- 64,750 sq. kms surface area (Canadian waters) and 7,400 kms of shoreline
- Over 120 Commercial Fishing Licenses
- One First Nation fishing agreement
- 6 Aboriginal Communal Fishing Licenses
- Total harvested under these licences averages over 4,500,000 kg annually, landed value over $7,500,000
- Sport fishing industry $176,000,000 annually
- 6 Conservation Officers, 1 Intelligence and Investigations Officer, and an Enforcement Manager
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| Officer inspecting nets used to commercially harvest fish. Conservation officers board commercial fishing tugs to inspect their harvest and bi-catch measure nets and to ensure proper fishing locations as per their food fishing licence. |
Commercial Fishery Enforcement
Monitoring and enforcing regulations and licence conditions associated with the commercial fishery is a high priority for the Ministry of Natural Resources Great Lakes Enforcement Units.
In 2008 approximately 31 million pounds of fish were commercially harvested from all of the Great Lakes. A landed value of approximately 27.4 million dollars was declared. (These numbers are based on quotas and market values which have been in the 30 million dollar range in recent years.)
Species fished commercially on the Great Lakes include; walleye, yellow perch, white perch, white bass, smelt, whitefish, lake trout, as well as a large number of coarse fish.
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| A typical day's commercial harvest on Lake Erie, approximately 3,000 lbs of yellow perch. |
Fines under the Fisheries Act can be as high as 1 million dollars.

Fish Markets & the Live Food Fishery
- Many communities in the GTA prefer to purchase live fish
- A substantial live food fishery has evolved in the Golden Horseshoe
- Most live fish species are native to Ontario waters and harvested legally by fishing methods under commercial fishing licences
- The live food fishery also includes import of species that do not exist in Ontario waters
- Directed inspections identify new species of interest for the live food fishery
The sale of angler caught fish is a growing area of concern for enforcement (pdf)
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Recreational Sport Fishery
The Great Lakes offer anglers a world class sport fishery for walleye, musky, yellow perch, as well as fishing opportunities for smallmouth bass, largemouth bass, pike, salmon and lake trout.
Conservation officers make thousands of angler contacts each year.
Conservation officer inspecting bass anglers on opening day in Long Point Bay |
Boating Safety Enforcement
Conservation officers also enforce boating safety, checking that required safety equipment is on board and that anglers and boaters are in compliance with the Liquor Licence Act. |
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Enforcing the Endangered Species Act on the Great Lakes

Conservation officers enforce the Endangered Species Act to protect species at risk in the Great Lakes basin such as the Lake Sturgeon and Atlantic Salmon.
The Upper Great Lakes/St. Lawrence population of Lake Sturgeon has been listed as threatened. There is a zero quota for these Lake Sturgeon. They can not be harvested and must be returned to the water immediately if caught.
Specialized Training for Marine Patrol

Conservation officers working in the Great Lakes environment must be able to operate a variety of different classes of vessels. To ensure adequate competency of these operators and to provide the officers with the required Transport Canada marine documents, the officers are required to complete the following courses;
- Marine Operators Course - to operate vessel up to 26 feet
- Large Launch Operators Course -to operate a launch class vessel over 28' with twin engines
- On water daily operation of vessels and learning patrol areas
The Early Days of Enforcement on the Great Lakes

In 1892 the province of Ontario took responsibility for managing and protected its resources through the formation of the Game and Fish Commission. The same year a large patrol vessel, the "Gilphie" (left), was purchased to patrol the vast waters of Lake Huron.
By 1910, the Ontario Game and Fish Commission had 13 steam, gas or sail powered vessels in its fleet to patrol the waters of the Great lakes. The Ministry of Natural Resources conservation officers have been involved in marine enforcement duties for over 100 years.

Prior to 1991 the Ministry of Natural Resources was divided into 49 administrative districts. There were 14 administrative districts that all bordered on the Great Lakes and most had Commercial Food Fishing Licences that were issued by the district.
In 1992 the creation of the Great Lakes Management Units and the transfer of dedicated enforcement positions signalled a need for dedicated resources to enforce commercial and sport fishing legislation on the Great Lakes.



To learn more about the history of patrolling the Great Lakes and the history of resource protection in Ontario visit the Ontario Archives online.
Great Lakes Enforcement Units Are Located At:
Lake Ontario - Picton with officers based out of Aurora & Vineland
Lake Erie - Wheatley with an officer based out of Aylmer
Upper Great Lakes - Owen Sound with officers based out of Parry Sound, Midland, Espanola, Sault Ste Marie & Thunder Bay



