Lake Ontario, the smallest of North America’s Great Lakes by surface area, is a significant aquatic ecosystem supporting a wide variety of fish species. Its deep, cool waters create diverse habitats, making it a crucial environment for both native populations and those introduced over time. This lake’s rich biodiversity underpins a robust recreational fishery and contributes to the region’s natural heritage.
Native Fish Species
Historically, Lake Ontario was home to numerous fish species that adapted to its unique conditions before substantial human impact. These native populations form the foundation of the lake’s ecological balance. Lake Trout, for example, were once the largest native salmonid in Lake Ontario, with some specimens exceeding 40 pounds and three feet in length. They are a cold-water species, found in cool, deep waters.
Lake Whitefish and various Cisco species were also native inhabitants, serving as important prey for larger predators. Lake Whitefish are bottom feeders, and now feed on invasive zebra and quagga mussels. Burbot, a freshwater cod, is another native species.
Yellow Perch and Smallmouth Bass are also indigenous to Lake Ontario, with Yellow Perch found near shore in shallower depths and Smallmouth Bass sensitive to pollution. Lake Sturgeon, though once nearly eradicated due to overfishing, habitat degradation, and invasive species, are gradually recovering with conservation efforts.
Introduced and Invasive Species
Human activities have led to the introduction of many fish species into Lake Ontario, some intentionally for sport fishing and others unintentionally, becoming invasive. Pacific Salmon, such as Chinook (King) and Coho, were introduced in the 1960s and 1970s and have established a sport fishery. Chinook salmon, the largest of the Pacific salmon in Lake Ontario, can reach over 30 pounds and are heavily stocked annually by New York State, with approximately 1.7 million Chinook and 250,000 Coho salmon stocked. Rainbow Trout, often referred to as Steelhead when migratory, and Brown Trout were also introduced, providing additional angling opportunities. Brown Trout, introduced from Europe, are primarily found along shorelines and in tributaries. Walleye have also made a notable comeback in recent years, contributing to the lake’s diverse fish community.
Invasive species, however, threaten the lake’s ecosystem. Alewife, a small, silvery fish, arrived in Lake Ontario in 1873, likely via canals. They became numerous, competing with native species like Cisco and Lake Whitefish, although they also serve as a food source for introduced salmon and trout. The Round Goby, from Eastern Europe, arrived via ballast water around 1990 and are bottom dwellers that compete with and prey on native fish. Sea Lamprey, a parasitic species, have impacted native fish populations, particularly Lake Trout, and are controlled annually. Zebra and Quagga mussels, though not fish, are invasive filter feeders that reduce plankton, affecting food sources.
Fishing in Lake Ontario
Lake Ontario offers diverse recreational fishing opportunities throughout the year, attracting anglers seeking various species. Trolling is a common angling method for targeting species across the vast lake, using multiple lines and specialized gear.
Chinook and Coho salmon are popular, with peak fishing seasons from late summer into fall. Brown Trout fishing is popular along the shorelines, and Lake Trout are targeted in deeper, cooler waters. Rainbow Trout, or Steelhead, are also a favorite when they run into tributaries. Beyond salmon and trout, Lake Ontario supports fishing for Smallmouth Bass, Largemouth Bass, Northern Pike, Yellow Perch, and Walleye.
Conservation and Management Efforts
Protecting Lake Ontario’s fish populations involves conservation and management strategies. These efforts address challenges such as habitat degradation, pollution, and invasive species. Stocking programs are a tool, with salmon and trout released annually to support recreational fisheries.
Fishing regulations are implemented to manage fish stocks and ensure sustainable harvesting. Habitat restoration projects, like spawning beds, aim to support native fish recovery, including Lake Sturgeon and Lake Whitefish. International cooperation, often coordinated through bodies like the Great Lakes Fishery Commission, is also crucial for managing shared resources and controlling invasive species like the Sea Lamprey. These efforts maintain a healthy and diverse fish community for future generations.