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T h e L a k e o f t h e W o o d sT h e L a k e o f t h e W o o d s
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Home to species that are absent/rare in the rest of Ontario, Canada, and the world.
White-tailed Jack Rabbit
Franklins Squirrel American White Pelican Piping Plover
Green-faced clubtail dragonfly
Some examples include:
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LoW remnant of glacial Lake Agassiz- largest lake in N. America
during the last deglaciation
Mud Portage petroglyphs: evidence for 1st inhabitants, late Paleoor Plano people ~9,300 yr BP
~2,200 yr BP: arrival of Early Woodland people including
the Laurel people
harvested, cooked & stored wild rice
~AD 1688 first European to sight LoW: Jacques De Noyen
18th & 19th centuries: LoW a hub for fur traders and missionaries
1850: Gold discovered
Source: Windows to the Universe, at http://www.windows.ucar.edu/
Source: Robertson and McCracken 2003
Source: Robertson and McCracken 2003
Lake of the Woods
Lake Agassiz
http://www.windows.ucar.edu/http://www.windows.ucar.edu/7/31/2019 Intro to the LoW
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~1877: Canadian Pacific Railway in the region
Late 1800s early 1900s- Rat Portage (now Kenora)
major lumber industry centre
1872: 1st steamship on the LoW
~1887 to ~1900: dams built at northern outlets to the Winnipeg R. average water level rises by ~2m
~1890-1900: Sturgeon fishing frenzy: caviar
within a decade unregulated sturgeon fishery went fromboom (350,000 kilos/year) to bust
Today LoW is still a major tourist attraction
Source: Robertson and McCracken 2003
Source: Robertson and McCracken 2003
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-96
-96
-95
-95
-94
-94
-93
-93
49 49
50 50
0510
km
OntarioManitob
a
Minnesota
Kenora
-95
-95
-90
-90
-85
-85
-80
-80
-75
-75
45 45
50 50
55 55
Man
itoba
Ontario
Minnesota
One of Ontarios largest inland lakes: ~385,000 ha (excluding Shoal Lake)
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Numerous depositional basins Hundreds of inlets and bays >14,500 islands
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Large drainage basin 69,750 km2
Low lake to drainage basin area ratio Highly susceptible to activities in its catchment
Map by Gartner Lee Ltd.
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BigTraverseBay
Kenora
Modified from Robertson & McCracken 2003
RainyRiver
Rainy Riverprovides ~70% of
inflow through LoW
Water flowsnorthward through
main channel
Major outlet isWinnipeg R. in the
north
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Site
PP-12
PP-13
PP-14PP
-6
PP-15PP
-5PP
-4PP
-7PP
-3PP
-2PP
-8PP
-1PP
-9
PP-11
PP-18
PP-10
PP-17
PP-19
PP-20
PP-16
Totalphosphorus
(
gL-1)
5
10
15
20
25
30
Whitefish Bay
PP-1
Bigstone Bay
Results of this initiative published inJ. Great Lakes Res. Pla et al. 200531:253-266
Long-term monitoring has shown LoW experiences significant inter-annual andspatial variability in nutrients with highest concentrations in late summer
Strong TP gradient tracks direction of flow from the Rainy River (Pla et al. 2005) Higher TP concentrations along main channel and in the south end
Summer total phosphorus (TP) measurements
Low Medium High
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August 31st
July 18th
June 19th
(Terra MODIS images G. McCullough, U. of Winnipeg)
Typically blooms occur in mid summer in the south end of the lakeand in late summer to early fall, at the north end.
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There is a perception that water quality in the LoW has deteriorated inrecent years due to a reported increase in the frequency and intensity ofcyanobacterial algal blooms.
Interest in determining if this is true
Interest in understanding why
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Total phosphorus (TP) important, limiting nutrient for algal growth Much interest in determining whether TP has changed historically
Has TP been historically high in LoW?
Has TP increased recently?
Historical documents back to early 1820s describe algal blooms
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The islands were numerous and crowded, the water shoaland foul, frequently with a green scum of vegetable matter
- Major Joseph Delafield, July 30th, 1823
the water became tinged with green, derived from aminute vegetable growth
- S. J. Dawson, Summer 1857
deposits of green vegetable matter in thelakes bays during the summer.
- objection to a proposal to use LOW to supply clean
water to Winnipeg 1883
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Although historical reports give important insights into past environmentalconditions, they cannot provide us with answers to key lake managementquestions
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1) What is the natural or baseline condition of the lake?
2) Has the water quality changed since pre-development (orpre-industrial) times?
3) If so, when did these changes occur?
4) What is the direction and magnitude of this change?
5) What are the possible reasons for this change?
Answers to these questions can provide evidence for possible mechanisms
underlying these changes.
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Our research on the Lake of the Woods examines the remains of biologicalassemblages preserved in lake sediments as a key to past environmental conditions.
To learn more aboutPaleolimnologyand our work on the Lake of the Woods,
visit our slideshow Spotlight on Paleolimnology featured on our HomePage.
Some examples of remains preserved in lake sediments:
Diatoms: siliceous algae Chironomids: non-biting midges Cladocerans: water fleas