Lake Ontario

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Lake Ontario
Grants No. 0528674 (NSF) and NA06OAR4170017 (NOAA)
Created by Helen Domske, NY Sea Grant
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Lake Ontario
Lake Ontario is ranked as the 12th largest lake
in the world. Lake Ontarios surface area of
7,340 square miles (18,960 sq km) makes it the
smallest of the Great Lakes.
Credit GL Fisheries Commission
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Bathymetry of Lake Ontario
NOAA GLERL
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Lake Ontario Facts
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.
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 Time 6 years
Credit GL Fisheries Commission
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Lake Ontario Facts
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.
Credit GL Fisheries Commission
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• About 93 of the water in Lake Ontario flows out
  to the St. Lawrence River the remaining 7
  leaves through evaporation.

Source USEPA
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From A LaMP-based Biodiversity Conservation
Strategy for Lake Ontario
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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
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Photos H. Domske
The Welland Canal connects Lake Erie and Lake
Ontario
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From http//www.wellandcanal.com
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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
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Lock doors closing
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• Lake water levels are influenced by dams and
  locks in the
• St. Lawrence River.

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Ecosystem Restructuring The Culprits Zebra
Quagga Mussels
Photos DFO
Credit SOLEC 2011
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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
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Cladophora
Credit Ontario Water Works Research Consortium
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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.

Mysis shrimp
Source NYS Department of Environmental
Conservation
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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.

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Native Lake Ontario Fishes 100 Years Ago
Whitefish
Lake Trout
Lake Herring
Atlantic Salmon
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The Historic Fish Community in Lake Ontario
Emerald shiner
Atlantic salmon
Lake whitefish
Planktivores
Lake trout
Blue pike
Bloater
Lake herring
Walleye
Burbot
Predators
Yellow perch
White bass
Lake sturgeon
American eel
Deep-water sculpin
Benthic
Bullheads/Catfish
Bowfin
Smallmouth bass
Slimy sculpin
Credit Dave McNeill, NYSG
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The Present Lake Ontario Fish Community
Alewife
Sea lamprey
Non-native fish species
Native abundant
Rainbow smelt
Blueback herring
Round goby
Common carp
White perch
Brown trout
Atlantic salmon
Chinook salmon
Lake trout
Native reduced
Coho salmon
Intentionally stocked
Rainbow trout
Credit Dave MacNeill, NYSG
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Enter the Evil Alewife a Paradox
It looks benign, but it has been a serious
nuisance species and a benefit!?
Mass die-offs
Credit Dave MacNeill, NYSG
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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
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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
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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
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The Niagara River is the connecting channel
between Lake Erie and Lake Ontario and a major
source of hydroelectrical generation.
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Wetlands are important habitats on Lake Ontario
and serve as spawning areas for a number of fish
species.
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Tourism plays an important role in the economy
around Lake Ontario. The Seaway Trail National
Scenic Byway brings tourists to the area.
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Double-Crested Cormorants
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 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.
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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
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Cormorant Prey Species
Connie Adams, NYSDEC
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Bald Eagle

• Indicator Species
• Nesting Habitat Restoration Efforts
• 43 prime nesting sites identified in Ontario and
  New York
• Eight nesting platforms constructed

Photo OMNR