Lake Ontario

Grants No. 0528674 (NSF) and NA06OAR4170017 (NOAA)

Created by: Helen Domske, NY Sea Grant

Lake OntarioLake Ontario is ranked as the 12th 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

Bathymetry of Lake Ontario

NOAA GLERL

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 Depth283 feet

86 metersLand Drainage Area

24,720 sq. mi.64,030 sq. km.

Maximum Depth802 feet

244 metersShoreline Length

712 mi.1,146 km.

Volume393 cu. mi.

1,640 cu. km.Population

US (2000); Can (2001)9,751,655

Water Area7,340 sq. mi.

18,960 sq. km.Retention Time 6 years

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

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

Source: USEPA

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

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

The Welland Canal connects Lake Erie and Lake Ontario

Photos: H. Domske

From: http://www.wellandcanal.com

Welland Canal Facts1st 2nd 3rd 4th (1829) (1845) (1887)

(1932)

Number Of Locks 40 27 26 8Width Of Locks 6.7m 8.1m 13.7m 24.4mLength Of Locks 33.5m 45.7m 82.3m 261.8mDepth 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 thanpicks and shovels. The men on these crews were paid about a half a dollarfor a day's work. The operation of the canal also required a great deal ofphysical 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 thename of towpath. The total cost of the canal was 8 million dollars and theman responsible for initiating the project was a young entrepreneur by thename of William Hamilton Merritt. He would later become known as thefounding father of the Welland Canal. From: http://www.wellandcanal.com

Lock doors closing…

Lake water levels are influenced by dams and locks in the

St. Lawrence River.

Ecosystem Restructuring: The Culprits – Zebra & Quagga Mussels

Wet

Bio

mas

s g

/m2

+sh

ells

Total non-Dreissena Benthos & Dreissena Biomass ineast basin Lake Ontario (Station 81)

Fisheries and Oceans CanadaPêches et Océans Canada

Year

Dreissena

wet

Bio

mas

s g

/m2

+sh

ells

1 9 9 0 1 9 9 2 1 9 9 4 1 9 9 6 1 9 9 8 2 0 0 0 2 0 0 2 2 0 0 4 2 0 0 6 2 0 0 8 2 0 1 01

2

3

4

5

6

7

8

9

0

1 0 0

2 0 0

3 0 0

4 0 0

5 0 0

6 0 0

7 0 0

8 0 0

* * *

*

*

**

*

*

*

*

*Q Q

Q

Q

Q

Q

Q

D re issenanon-D re issena

Q*

.

Photos: D

FO

Credit: SOLEC 2011

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

Cladophora

Credit: Ontario Water Works Research Consortium

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

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.

Native Lake Ontario Fishes: 100 Years Ago

Whitefish

Lake Herring

Lake Trout

Atlantic Salmon

The Historic Fish Community in Lake Ontario

Bloater

Lake trout Blue 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

The Present Lake Ontario Fish Community

Native: abundant

Inte

ntio

nally

stoc

ked

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

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

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

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

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

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

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

Tourism plays an important role in the economy around Lake Ontario.

The Seaway Trail National Scenic Byway brings tourists to the area.

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

Double-Crested Cormorants

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

Cormorant Prey Species

Connie Adams, NYSDEC

Bald Eagle

Photo: OMNR

• Indicator Species• Nesting Habitat

Restoration Efforts• 43 prime nesting sites

identified in Ontario and New York

• Eight nesting platforms constructed