1. Lake Ontario Grants No. 0528674 (NSF) and NA06OAR4170017 (NOAA) Created by: Helen Domske, NY Sea Grant

2. Lake Ontario Lake Ontario is ranked as the 12 th largest lake in the world. Lake Ontario’s surface area of 7,340 square miles (18,960 sq km) makes it the smallest of the Great Lakes. Credit: GL Fisheries Commission

3. Bathymetry of Lake Ontario NOAA GLERL

4. The eastern outlet basin of the lake is much shallower and smaller than the main basin. However, with many embayments and peninsulas, the eastern outlet basin accounts for more than 50% of the lake's shoreline. The lake's drainage area is dominated by forests (49%) and agriculture (39%). A total of 7% of the basin is urbanized. Lake Ontario Facts Credit: GL Fisheries Commission Average Depth 283 feet 86 meters Land Drainage Area 24,720 sq. mi. 64,030 sq. km. Maximum Depth 802 feet 244 meters Shoreline Length 712 mi. 1,146 km. Volume 393 cu. mi. 1,640 cu. km. Population US (2000); Can (2001) 9,751,655 Water Area 7,340 sq. mi. 18,960 sq. km. Retention Time6 years

5. Lake Ontario's current nutrient levels are characteristic of an oligotrophic (low productivity) system. A total of 86% of inflows comes from the upper Great Lakes and Lake Erie through the Niagara River. Water quality is affected by upstream sources and inputs from local industry, urban development, agriculture, and landfills. Lake Ontario Facts Credit: GL Fisheries Commission

6.  About 93% of the water in Lake Ontario flows out to the St. Lawrence River; the remaining 7% leaves through evaporation. Source: USEPA

7. From: A LaMP-based Biodiversity Conservation Strategy for Lake Ontario

8. Native Migratory Fishes  Lake-tributary fishes: Lake sturgeon, Atlantic salmon, suckers, redhorse, walleye, brook trout  Lake-ocean fishes: American eel  Wetland spawners: Northern pike, muskellunge, and yellow perch From: A LaMP-based Biodiversity Conservation Strategy for Lake Ontario

9. The Welland Canal connects Lake Erie and Lake Ontario Photos: H. Domske

10. From: http://www.wellandcanal.com

11. Welland Canal Facts 1st 2nd 3rd 4th (1829) (1845) (1887) (1932) Number Of Locks 40 27 26 8 Width Of Locks 6.7m 8.1m 13.7m 24.4m Length Of Locks 33.5m 45.7m 82.3m 261.8m Depth Of Canal 2.4m 2.7m 4.3m 8.2m The building of the canal was a labor intensive venture. Construction crews\ made up of European immigrants had very few tools to work with other than picks and shovels. The men on these crews were paid about a half a dollar for a day's work. The operation of the canal also required a great deal of physical labor as horses and oxen were used to tow the ships (schooners) from one lock to another on paths that still exist today as streets by the name of towpath. The total cost of the canal was 8 million dollars and the man responsible for initiating the project was a young entrepreneur by the name of William Hamilton Merritt. He would later become known as the founding father of the Welland Canal. From: http://www.wellandcanal.com

12. Lock doors closing…

13. Lake water levels are influenced by dams and locks in the St. Lawrence River.

14. Ecosystem Restructuring: The Culprits – Zebra & Quagga Mussels Photos: DFO Credit: SOLEC 2011

15. In Lake Ontario the dominant attached alga is Cladophora. In the 1960s and 1970s this alga caused serious problems in the near shore zone. It had explosive growth, which detached and fouled local beaches at the peak of the summer recreational season. Research at that time showed that Lake Ontario was receiving an excess of phosphorus, which normally limits Cladophora growth in the shallow, well- illuminated near shore zone. Credit: Ontario Water Works Research Consortium

16. Cladophora

17. Nearshore Zone Food Web and Fisheries Highlights   Although zebra mussels once dominated the nearshore zone, they are now found primarily in water less than 10 feet deep. Quagga mussels now dominate the lake bottom from the water's edge to depths beyond 400 feet.   At the base of the food web, the abundance of green algae (phytoplankton) is lower than what would be expected for the current level of phosphorus (plant nutrient) in the water due to the effects of zebra and quagga mussels.   Spring abundance of diatoms, a microscopic algae that is an important food source for zooplankton and opossum shrimp (Mysis), has declined in the Eastern Basin since the establishment of zebra and quagga mussels. Source: NYS Department of Environmental Conservation Mysis shrimp

18. Early Commercial Pressures   Commercial fishing practices are also partially to blame for the demise of Atlantic salmon in Lake Ontario.   Spawning salmon were captured or hindered by pound nets and weirs.

19. Native Lake Ontario Fishes: 100 Years Ago Whitefish Lake Herring Lake Trout Atlantic Salmon

20. The Historic Fish Community in Lake Ontario Bloater Lake troutBlue pike Smallmouth bass Bowfin Burbot Walleye White bass Yellow perch Emerald shiner Bullheads/Catfish American eel Lake whitefish Deep-water sculpin Slimy sculpin Lake sturgeon Lake herring Predators Planktivores Benthic Atlantic salmon Credit: Dave McNeill, NYSG

21. The Present Lake Ontario Fish Community Native: abundant Intentionally stocked Non-native fish species Alewife Sea lamprey Rainbow smelt White perch Blueback herring Common carp Round goby Lake trout* Chinook salmon Brown trout Coho salmon Native: reduced Rainbow trout Atlantic salmon* Credit: Dave MacNeill, NYSG

22. Enter the “Evil Alewife”: a Paradox Mass die-offs It looks benign, but it has been a serious nuisance species and a benefit!? Credit: Dave MacNeill, NYSG

23. Important Time Periods for Lake Ontario Fisheries:  Early-late 1800s: Welland Canal system, lamprey enter, watershed changes: deforestation, damming, siltation, unregulated salmon fishing, alewives introduced, salmon collapse and extirpated.  1920s and 1930s: Sea lamprey predation, highly-prized fish populations collapse, increased harvest on alternative fish species, introduction of smelt and double-crested cormorant, smelt and alewife dominate offshore, alewife die-offs, human population growth, industry, nutrient inputs.  1950s and 1960s: Population collapses of many native species, severe decline of lake trout/burbot, St. Lawrence Seaway opens, TFM used for sea lamprey control, massive alewife die-offs, contaminant loadings, hydroelectric power use, successful stocking, concern for nutrient loading, double-crested cormorants decline. Credit: Dave MacNeill, NYSG

24. Important Time Periods for Lake Ontario Fisheries:  1970s and 1980s: Beginning/expansion of stocking efforts, sportfishery worth millions of dollars, alewives and smelt under some control, invasive species introductions by ballast water, nutrient/toxic abatement, signs of successful lake rehabilitation.  1990s and early 2000s: Stocking rates/sportfisheries peak & decline, more ballast invasions with negative impacts on fish/ecosystems, double-crtested cormorant populations explode, alewife/smelt decline, signs of successful lake trout reproduction, fisheries sustainability? Credit: Dave MacNeill, NYSG

25. Results of Human Impacts on Lake Ontario Fish Communities:  A shift from dominant species that are large and long- lived (i.e. lake trout, Atlantic salmon, lake sturgeon) to smaller, short-lived fish species.  A shift in populations with relatively stable populations (numbers and age) to unstable populations that fluctuate considerably (numbers/ages).  A shift from populations with diverse habitat preferences and diverse physical characteristics to populations that thrive only in narrow range of habitats.  A shift in abundance of highly-prized, commercial fish species for human food, to species to fish species that are of little or no commercial value. Credit: Dave MacNeill, NYSG

26. The Niagara River is the connecting channel between Lake Erie and Lake Ontario and a major source of hydroelectrical generation.

27. Wetlands are important habitats on Lake Ontario and serve as spawning areas for a number of fish species.

28. Tourism plays an important role in the economy around Lake Ontario. The Seaway Trail National Scenic Byway brings tourists to the area.

29. Double crested cormorants can have negative impacts on islands and other habitats where they nest. Their excretions and nesting activities destroy ground vegetation and trees around nest, eliminating habitat for other birds and animals. There are reported cases where cormorants have displaced other colonial nesting species such as great blue herons, common terns and black-crowned night herons from their nesting sites. New York State used "oiling" of cormorant eggs to prevent their hatching. DEC also destroys nests and "hazes" nesting areas in spring and fall to try to prevent the birds from feeding on fish. Double-Crested Cormorants

30. One of 6 cormorant species native to North America, 35 worldwide, only species typically found inland. First nested in Eastern Lake Ontario in 1945. Populations grew, by 1970 was 125 pairs in all the Great Lakes and at one point reached 750,000. Connie Adams, NYSDEC

31. Cormorant Prey Species Connie Adams, NYSDEC

32. Bald Eagle Photo: OMNR Indicator Species Indicator Species Nesting Habitat Restoration Efforts Nesting Habitat Restoration Efforts 43 prime nesting sites identified in Ontario and New York 43 prime nesting sites identified in Ontario and New York Eight nesting platforms constructed Eight nesting platforms constructed