2008 Lake System

Health Monitoring

Program

Data Report

February 2009

Prepared by The District Municipality of Muskoka

Planning and Economic Development Department

With Technical Support from the Dorset Environmental Science Centre, Ministry of the Environment

2008 Lake System Health Monitoring Program Data Report

Table of Contents

Purpose ...... 2

Contents ...... 2

Table 1: 2008 Total Phosphorus Data ...... 3

Table 2: 2008 Secchi Depth Measurements ...... 4

Sample Lake Data Sheet ...... 5

2008 Lake Data Sheets ...... 6

2008 Lake Joseph Monitoring Data ...... 90

2008 Land Use Survey Data Tables...... 99

2008 Aquatic Invertebrate Data Sheets ...... 102

2008 Terrestrial Plot Monitoring Summary Tables ...... 124

Appendix 1 Interpretation of water quality data ...... 126

Appendix 2 Interpretation of aquatic invertebrate monitoring results...... 129

1 2008 Lake System Health Monitoring Program Data Report

Purpose

This data report contains the data collected during the 2008 Lake System Health Monitoring Program. The 2008 Lake System Health Monitoring Program Year End Report contains information on monitoring parameters and sampling procedures.

Contents

1. 2008 Phosphorus Data Table 2. 2008 Secchi Depth Measurements Table 3. 2008 Lake Data Sheets 4. 2008 Lake Joseph Monitoring Data 5. 2008 Land Use Survey Data Tables 6. 2008 Aquatic Invertebrate Data Sheets 7. 2008 Terrestrial Plot Monitoring Summary Table

2 2008 Lake System Health Monitoring Program Data Report

Table 1: 2008 Total Phosphorus Data

TP1 TP2 Ave TP TP1 TP2 Ave TP Lake Name Lake Name (µg/L) (µg/L) (µg/L) (µg/L) (µg/L) (µg/L) Axle 7.8 7.2 7.5 Mirror 6.8 6.6 6.7 Baxter 12.4 9.4 10.9 Moot 10.4 10.4 10.4 Bella 10.2 8.8 9.5 Muskoka - Bala Bay 6.8 6.2 6.5 Bird 12.6 12.2 12.4 Muskoka - Dudley Bay 7.0 7.2 7.1 Brandy 20.4 20.6 20.5 Muskoka - Main 5.6 5.6 5.6 Buck HTE 16.2 13.6 14.9 Muskoka - Muskoka Bay 12.6 11.8 12.2 Buck LOB 6.6 6.6 6.6 Muskoka - Whiteside Bay 6.8 6.2 6.5 Cassidy 10.0 12.4 11.2 Neilson 12.2 11.6 11.9 Chub HTE 8.0 8.2 8.1 North Bay 10.8 10.8 10.8 Chub LOB 6.6 7.2 6.9 North Muldrew 10.0 8.8 9.4 Clear (Torrance) 6.4 6.6 6.5 Penfold 18.0 17.4 17.7 Clearwater GR 5.6 6.6 6.1 Peninsula - East 12.2 11.4 11.8 Clearwater HTE 8.2 6.4 7.3 Peninsula - West 12.2 12.6 12.4 Cornall 9.2 9.2 9.2 Pigeon 8.8 8.4 8.6 Crosson 9.0 10.2 9.6 Porcupine 6.2 6.6 6.4 Fairy - Main 10.0 9.4 9.7 Rebecca 7.0 5.8 6.4 Fairy - NMRB 12.8 12.2 12.5 Ril 8.0 - 8.0 Fifteen Mile 6.0 6.0 6.0 Rosseau - Brackenrig Bay 10.2 10.0 10.1 Foote 9.4 8.0 8.7 Rosseau - E. Portage Bay 7.8 7.8 7.8 Go Home 7.4 - 7.4 Rosseau - Main 6.2 6.0 6.1 Grandview 4.4 4.8 4.6 Rosseau - North 6.6 7.0 6.8 Gull 6.0 7.6 6.8 Rosseau - Skeleton Bay 6.8 7.0 6.9 Gullfeather 9.2 9.6 9.4 Sixteen Mile 9.0 9.4 9.2 Hardup 9.4 9.8 9.6 Skeleton 7.8 6.6 7.2 High 5.8 - 5.8 South Bay 14.2 20.0 17.1 Joseph - Cox Bay 6.6 - 6.6 South Muldrew 9.0 8.4 8.7 Joseph - Hamer Bay 3.8 4.4 4.1 South Nelson 9.0 10.0 9.5 Joseph - Joseph River 6.8 7.4 7.1 Sparrow 15.0 11.8 13.4 Joseph – L. Lake Joseph 7.0 6.6 6.8 Spring 6.0 5.6 5.8 Joseph - Main 4.8 4.6 4.7 Stewart 6.4 6.8 6.6 Joseph - North 4.8 4.6 4.7 Stoneleigh 11.8 11.4 11.6 Joseph - South 4.4 5.4 4.9 Tackaberry 5.0 5.6 5.3 Kahshe - Grant's Bay 10.0 11.2 10.6 Three Mile - Hammel's Bay 15.4 14.6 15.0 Kahshe - Main 11.8 11.4 11.6 Three Mile - Main 26.6 26.6 26.6 Leech 10.8 10.6 10.7 Three Mile GR 7.0 7.0 7.0 Little Long 7.6 7.2 7.4 Tooke 7.0 6.8 6.9 Long 7.4 6.6 7.0 Twelve Mile Bay - East 11.0 15.0 13.0 Long's 8.4 8.4 8.4 Twelve Mile Bay - West 5.2 5.4 5.3 Loon 19.4 20.6 20.0 Vernon - Hunter's Bay 10.8 11.4 11.1 McCrae 11.2 9.4 10.3 Vernon - Main 10.0 9.6 9.8 McDonald 10.8 11.0 10.9 Vernon - North Bay 10.2 11.4 10.8 McKay 7.4 7.8 7.6 Walker 4.8 5.0 4.9 Medora 6.8 7.4 7.1 Young 10.4 6.8 8.6

3 2008 Lake System Health Monitoring Program Data Report

Table 2: 2008 Secchi Depth Measurements

May Aug Ave May Aug Ave Lake Name Secchi Secchi Secchi Lake Name Secchi Secchi Secchi (m) (m) (m) (m) (m) (m) Axle 5.2 5.3 5.3 Mirror 3.8 4.3 4.1 Baxter 4.1 5.0 4.6 Moot 1.9 1.1 1.5 Bella 3.0 4.0 3.5 Muskoka - Bala Bay 3.9 4.2 4.1 Bird 2.3 2.9 2.6 Muskoka - Dudley Bay 3.5 3.9 3.7 Brandy 1.1 1.7 1.4 Muskoka - Main 3.5 4.0 3.8 Buck HTE 1.7 1.2 1.5 Muskoka - Muskoka Bay 2.6 3.6 3.1 Buck LOB 4.7 5.1 4.9 Muskoka - Whiteside Bay 4.0 3.9 4.0 Cassidy 3.0 2.7 2.9 Neilson 2.3 2.2 2.3 Chub HTE 2.3 2.8 2.6 North Bay 3.3 3.3 3.3 Chub LOB 2.3 2.6 2.5 North Muldrew 2.1 3.3 2.7 Clear (Torrance) 5.1 5.5 5.3 Penfold 2.0 0.8 1.4 Clearwater GR 3.5 6.2 4.9 Peninsula - East 3.1 3.2 3.2 Clearwater HTE 4.2 3.0 3.6 Peninsula - West 3.2 4.0 3.6 Cornall 3.1 2.4 2.8 Pigeon 3.9 4.0 4.0 Crosson 3.0 2.9 3.0 Porcupine 2.8 2.8 2.8 Fairy - Main 2.9 2.7 2.8 Rebecca 3.9 3.9 3.9 Fairy - NMRB 2.6 3.0 2.8 Ril 2.0 2.5 2.3 Fifteen Mile 6.9 3.4 5.2 Rosseau - Brackenrig Bay 2.1 2.9 2.5 Foote 2.1 2.0 2.1 Rosseau – E. Portage Bay 4.0 5.5 4.8 Go Home 2.0 3.0 2.5 Rosseau - Main 6.4 5.4 5.9 Grandview 7.1 7.3 7.2 Rosseau - North 5.1 5.1 5.1 Gull 2.2 2.7 2.5 Rosseau - Skeleton Bay 3.7 5.2 4.5 Gullfeather 2.2 2.0 2.1 Sixteen Mile 4.0 2.9 3.5 Hardup 4.6 4.1 4.4 Skeleton 8.1 8.5 8.3 High 5.4 5.4 5.4 South Bay 3.1 4.9 4.0 Joseph - Cox Bay 3.9 6.2 5.1 South Muldrew 2.6 3.0 2.8 Joseph - Hamer Bay 6.1 5.9 6.0 South Nelson 3.0 2.4 2.7 Joseph - Joseph River 3.0 4.0 3.5 Sparrow 3.8 4.2 4.0 Joseph – L. Lake Joseph 3.5 4.8 4.2 Spring 4.4 4.0 4.2 Joseph - Main 4.0 6.1 5.1 Stewart 2.8 4.0 3.4 Joseph - North 6.0 5.8 5.9 Stoneleigh 1.8 1.3 1.6 Joseph - South 5.0 5.9 5.5 Tackaberry 4.7 5.0 4.9 Kahshe - Grant's Bay 2.9 2.3 2.6 Three Mile - Hammel's Bay 3.1 2.1 2.6 Kahshe - Main 3.0 2.8 2.9 Three Mile - Main 0.5 1.4 1.0 Leech 2.7 2.9 2.8 Three Mile GR 6.8 4.1 5.5 Little Long 2.9 3.7 3.3 Tooke 5.4 4.8 5.1 Long 4.5 4.9 4.7 Twelve Mile Bay - East 1.6 3.9 2.8 Long's 1.9 1.6 1.8 Twelve Mile Bay - West 9.4 7.3 8.4 Loon 2.4 2.9 2.7 Vernon - Hunter's Bay 2.6 2.5 2.6 McCrae 3.9 4.3 4.1 Vernon - Main 2.2 2.7 2.5 McDonald 4.0 4.1 4.1 Vernon - North Bay 2.0 2.7 2.4 McKay 2.9 1.9 2.4 Walker 5.5 4.9 5.2 Medora 4.7 3.8 4.3 Young 2.9 5.2 4.1

4 2008 Lake System Health Monitoring Program Data Report

Sample Lake Data Sheet

A cold water fishery is a lake that is Current 10- managed by year average the Ministry of for phosphorus. Natural This value Resources for should remain Lake trout below the habitat. Threshold Value shown Sensitivity of the lake to phosphorus based on the graph on the lake’s responsiveness to phosphorus below. inputs and the mobility of phosphorus within the watershed.

Thermocline – where the water temperature drops quickly.

Threshold = background level of phosphorus + 50%. A lake is considered “over threshold” (OT) if the measured long term average and modeled phosphorus concentration are both above this value. An OT lake can be de-listed after 3 consecutive phosphorus measurements are below its threshold value.

Background = the estimated Phosphorus and Secchi concentration of phosphorus depth measurements over from natural sources i.e. the time. An increase in concentration of phosphorus phosphorus usually results in present if there was no a decrease in Secchi depth development on the lake. and vice versa.

5 2008 Lake System Health Monitoring Program Data Report

2008 Lake Data Sheets

The District Municipality of Muskoka

6 2008 Lake System Health Monitoring Program Data Report

Axle Lake

Municipality: Lake of Bays Watershed: Lake of Bays 2 2 Surface Area: 0.20 km Watershed Area (excluding lake): 0.39 km Maximum Depth: 10 m Cold Water Fishery? No Wetland Area: 15 % Secchi Depth (10-year average): 6.0 m Phosphorus (10-year average 1999-2008): 8.5 g/L Sensitivity: Moderate

May 2008 August 2008

0 5 10 15 20 0 5 10 15 20 25 0 0 1 1 2 2 3 3 4 4

5 5 Depth (m) Depth Depth (m) Depth 6 6 7 7 8 8 9 9

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

7 2008 Lake System Health Monitoring Program Data Report

Baxter Lake

Municipality: Georgian Bay Watershed: West 2 2 Surface Area: 0.45 km Watershed Area (excluding lake): 2.3 km Maximum Depth: 16 m Cold Water Fishery? No Wetland Area: 4.13 % Secchi Depth (10-year average): 4.7 m Phosphorus (10-year average 1999-2008): 9.7 g/L Sensitivity: Moderate (OT)

May 2008 August 2008 0 5 10 15 20 0 5 10 15 20 25 0 0

5 5

10 10

15 15 Depth (m) Depth Depth (m)Depth

20 20

25 25

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

8 2008 Lake System Health Monitoring Program Data Report

Bella Lake

Municipality: Lake of Bays Watershed: Lake Vernon 2 2 Surface Area: 3.45 km Watershed Area (excluding lake): 11.65 km Maximum Depth: 35 m Cold Water Fishery? Yes Wetland Area: 25 % Secchi Depth (10-year average): 4.6 m Phosphorus (10-year average 1999-2008): 7.9 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25

0 0 5 5 10 10 15 15 20 20

Depth (m)Depth 25

Depth (m) Depth 25 30 30 35 35 40 40

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

9 2008 Lake System Health Monitoring Program Data Report

Bird Lake

Municipality: Bracebridge Watershed: Muskoka River 2 2 Surface Area: 0.64 km Watershed Area (excluding lake): 6.21 km Maximum Depth: 5 m Cold Water Fishery? No Wetland Area: 10 % Secchi Depth (10-year average): 3.0 m Phosphorus (10-year average 1999-2008): 11.0 g/L Sensitivity: Moderate (OT)

May 2008 August 2008

0 2 4 6 8 10 12 0 5 10 15 20 25 0 0

1 1

2 2

3 3

Depth (m) Depth 4 (m) Depth 4

5 5

6 6

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

10 2008 Lake System Health Monitoring Program Data Report

Brandy Lake

Municipality: Muskoka Lakes Watershed: Lake Muskoka 2 2 Surface Area: 1.15 km Watershed Area (excluding lake): 39.85 km Maximum Depth: 8 m Cold Water Fishery? No Wetland Area: 14 % Secchi Depth (10-year average): 1.3 m Phosphorus (10-year average 1999-2008): 28.4 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 20 0 5 10 15 20 25 30 0 0 1 1 2 2 3 3 4 4 5 5 Depth (m)Depth Depth (m) Depth 6 6 7 7 8 8 9 9

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

11 2008 Lake System Health Monitoring Program Data Report

Buck Lake

Municipality: Huntsville Watershed: Lake Vernon 2 2 Surface Area: 2.5 km Watershed Area (excluding lake): 73.25 km Maximum Depth: 25 m Cold Water Fishery? No Wetland Area: 2 % Secchi Depth (10-year average): 1.6 m Phosphorus (10-year average 1999-2008): 12.5 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0

5 5

10 10

15 15

Depth (m) Depth Depth (m)Depth

20 20

25 25

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

12 2008 Lake System Health Monitoring Program Data Report

Buck Lake

Municipality: Lake of Bays Watershed: Dwight Bay 2 2 Surface Area: 0.41 km Watershed Area (excluding lake): 1.57 km Maximum Depth: 32 m Cold Water Fishery? Yes Wetland Area: 20 % Secchi Depth (10-year average): 5.5 m Phosphorus (10-year average 1999-2008): 7.6 g/L Sensitivity: Moderate

May 2008 August 2008

0 5 10 15 0 5 10 15 20 25 0 0

5 5

10 10

15 15 Depth (m)Depth 20 (m)Depth 20

25 25

30 30

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

13 2008 Lake System Health Monitoring Program Data Report

Cassidy Lake

Municipality: Muskoka Lakes Watershed: Moon River 2 2 Surface Area: 0.55 km Watershed Area (excluding lake): 7.4 km Maximum Depth: 8 m Cold Water Fishery? No Wetland Area: 8.86 % Secchi Depth (10-year average): 3.1 m Phosphorus (10-year average 1999-2008): 11.4 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0 1 1 2 2 3 3 4 4 5 5

Depth (m)Depth 6 (m)Depth 6 7 7 8 8 9 9

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

14 2008 Lake System Health Monitoring Program Data Report

Chub Lake

Municipality: Huntsville Watershed: Mary Lake 2 2 Surface Area: 0.27 km Watershed Area (excluding lake): 0.85 km Maximum Depth: 12 m Cold Water Fishery? No Wetland Area: 20 % Secchi Depth (10-year average): 2.9 m Phosphorus (10-year average 1999-2008): 9.3 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 20 0 5 10 15 20 25 0 0

2 2

4 4

6 6

8 8 Depth (m) Depth Depth (m) Depth 10 10

12 12

14 14

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

15 2008 Lake System Health Monitoring Program Data Report

Chub Lake

Municipality: Lake of Bays Watershed: Muskoka River 2 2 Surface Area: 0.34 km Watershed Area (excluding lake): 2.68 km Maximum Depth: 27 m Cold Water Fishery? No Wetland Area: 15 % Secchi Depth (10-year average): 2.7 m Phosphorus (10-year average 1999-2008): 8.6 g/L Sensitivity: Moderate

May 2008 August 2008

0 5 10 15 0 5 10 15 20 25 0 0

2 2

4 4

6 6

8 8 Depth (m)Depth Depth (m) Depth 10 10

12 12

14 14

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

16 2008 Lake System Health Monitoring Program Data Report

Clear (Torrance) Lake

Municipality: Muskoka Lakes Watershed: Lake Muskoka 2 2 Surface Area: 1.52 km Watershed Area (excluding lake): 0.84 km Maximum Depth: 16 m Cold Water Fishery? No Wetland Area: 0 % Secchi Depth (10-year average): 7.4 m Phosphorus (10-year average 1999-2008): 6.0 g/L Sensitivity: Moderate (OT)

May 2008 August 2008 0 5 10 15 20 0 5 10 15 20 25 0 0 2 2 4 4 6 6 8 8 10 10 12 12 Depth (m) Depth (m) Depth 14 14 16 16 18 18 20 20

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

17 2008 Lake System Health Monitoring Program Data Report

Clearwater Lake

Municipality: Gravenhurst Watershed: Sparrow Lake 2 2 Surface Area: 0.7 km Watershed Area (excluding lake): 0.88 km Maximum Depth: 29 m Cold Water Fishery? Yes Wetland Area: 15 % Secchi Depth (10-year average): 5.4 m Phosphorus (10-year average 1999-2008): 6.3 g/L Sensitivity: Moderate (OT)

May 2008 August 2008

0 5 10 15 20 0 5 10 15 20 25 0 0

5 5

10 10

15 15

Depth (m) Depth 20 (m) Depth 20

25 25

30 30

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

18 2008 Lake System Health Monitoring Program Data Report

Clearwater Lake

Municipality: Huntsville Watershed: Muskoka River 2 2 Surface Area: 0.85 km Watershed Area (excluding lake): 2.29 km Maximum Depth: 8 m Cold Water Fishery? No Wetland Area: 10 % Secchi Depth (10-year average): 5.0 m Phosphorus (10-year average 1999-2008): 11.5 g/L Sensitivity: Moderate (OT)

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0 1 1 2 2 3 3 4 4 5 5 Depth (m)Depth 6 (m) Depth 6 7 7 8 8 9 9

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

19 2008 Lake System Health Monitoring Program Data Report

Cornall Lake

Municipality: Gravenhurst Watershed: Sparrow Lake 2 2 Surface Area: 0.25 km Watershed Area (excluding lake): 7.25 km Maximum Depth: 10 m Cold Water Fishery? No Wetland Area: 4.44 % Secchi Depth (10-year average): 3.0 m Phosphorus (10-year average 1999-2008): 13.0 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 20 0 5 10 15 20 25 0 0

2 2

4 4

6 6 Depth (m) Depth Depth (m) Depth 8 8

10 10

12 12

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

20 2008 Lake System Health Monitoring Program Data Report

Crosson Lake

Municipality: Bracebridge Watershed: Black River 2 2 Surface Area: 0.57 km Watershed Area (excluding lake): 4.44 km Maximum Depth: 26 m Cold Water Fishery? No Wetland Area: 20 % Secchi Depth (10-year average): 3.2 m Phosphorus (10-year average 1999-2008): 10.1 g/L Sensitivity: Moderate

May 2008 August 2008 0 2 4 6 8 10 12 0 5 10 15 20 25 0 0

5 5

10 10

15 15 Depth (m) Depth (m) Depth

20 20

25 25

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

21 2008 Lake System Health Monitoring Program Data Report

Fairy Lake – Main

Municipality: Huntsville Watershed: Mary Lake 2 2 Surface Area: 6.9 km Watershed Area (excluding lake): 39.9 km Maximum Depth: 60 m Cold Water Fishery? Yes Wetland Area: 2.43 % Secchi Depth (10-year average): 3.1 m Phosphorus (10-year average 1999-2008): 9.3 g/L Sensitivity: Moderate

May 2008 August 2008

0 5 10 15 0 5 10 15 20 25 0 0

10 10

20 20

30 30

40 40

Depth (m) Depth Depth (m) Depth 50 50

60 60

70 70

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

22 2008 Lake System Health Monitoring Program Data Report

Fairy Lake – North Muskoka River Bay

Municipality: Huntsville Watershed: Mary Lake 2 2 Surface Area: 0.49 km Watershed Area (excluding lake): 3.55 km Maximum Depth: 10 m Cold Water Fishery? Yes Wetland Area: 0 % Secchi Depth (10-year average): 3.1 m Phosphorus (10-year average 1999-2008): 9.0 g/L Sensitivity: Moderate

May 2008 August 2008 0 2 4 6 8 10 12 0 5 10 15 20 25 0 0

2 2

4 4

6 6

8 8 Depth (m) Depth (m) Depth 10 10

12 12

14 14

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

23 2008 Lake System Health Monitoring Program Data Report

Fifteen Mile Lake

Municipality: Lake of Bays Watershed: Dwight Bay 2 2 Surface Area: 0.81 km Watershed Area (excluding lake): 3.24 km Maximum Depth: 28 m Cold Water Fishery? Yes Wetland Area: 2.78 % Secchi Depth (10-year average): 5.8 m Phosphorus (10-year average 1999-2008): 6.9 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 20 0 5 10 15 20 25 0 0

5 5

10 10

15 15

20 20 Depth (m)Depth Depth (m) Depth 25 25

30 30

35 35

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

24 2008 Lake System Health Monitoring Program Data Report

Foote Lake

Municipality: Lake of Bays Watershed: Lake Vernon 2 2 Surface Area: 1.25 km Watershed Area (excluding lake): 9.4 km Maximum Depth: 11 m Cold Water Fishery? No Wetland Area: 9.29 % Secchi Depth (10-year average): 2.5 m Phosphorus (10-year average 1999-2008): 8.9 g/L Sensitivity: Moderate

May 2008 August 2008

0 5 10 15 20 0 5 10 15 20 25 0 0 2 2

4 4

6 6 Depth (m) Depth 8 (m) Depth 8

10 10

12 12

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

25 2008 Lake System Health Monitoring Program Data Report

Go Home Lake

Municipality: Georgian Bay Watershed: Musquash River 2 2 Surface Area: 6.7 km Watershed Area (excluding lake): 23 km Maximum Depth: 32 m Cold Water Fishery? No Wetland Area: 20 % Secchi Depth (10-year average): 4.0 m Phosphorus (10-year average 1999-2008): 8.7 g/L Sensitivity: Moderate (OT)

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 30 0 0

5 5

10 10

15 15

20 20

Depth (m)Depth Depth (m) Depth 25 25

30 30

35 35

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

26 2008 Lake System Health Monitoring Program Data Report

Grandview Lake

Municipality: Lake of Bays Watershed: Muskoka River 2 2 Surface Area: 0.75 km Watershed Area (excluding lake): 1.56 km Maximum Depth: 26 m Cold Water Fishery? No Wetland Area: 15 % Secchi Depth (10-year average): 5.7 m Phosphorus (10-year average 1999-2008): 7.3 g/L Sensitivity: Moderate

May 2008 August 2008

0 2 4 6 8 10 12 0 5 10 15 20 25 0 0

5 5

10 10

15 15 Depth (m) Depth Depth (m) Depth

20 20

25 25

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

27 2008 Lake System Health Monitoring Program Data Report

Gull Lake

Municipality: Gravenhurst Watershed: Lake Muskoka 2 2 Surface Area: 1.35 km Watershed Area (excluding lake): 3.6 km Maximum Depth: 7 m Cold Water Fishery? No Wetland Area: 5 % Secchi Depth (10-year average): 3.3 m Phosphorus (10-year average 1999-2008): 6.3 g/L Sensitivity: Moderate

May 2008 August 2008 10 10.2 10.4 10.6 10.8 11 11.2 11.4 0 5 10 15 20 25 0 0 1 1 2 2 3 3 4 4

Depth (m) Depth 5 (m) Depth 5 6 6 7 7 8 8

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

28 2008 Lake System Health Monitoring Program Data Report

Gullfeather Lake

Municipality: Bracebridge Watershed: Black River 2 2 Surface Area: 0.67 km Watershed Area (excluding lake): 9.93 km Maximum Depth: 11 m Cold Water Fishery? No Wetland Area: 9 % Secchi Depth (10-year average): 1.9 m Phosphorus (10-year average 1999-2008): 10.6 g/L Sensitivity: Moderate

May 2008 August 2008 0 2 4 6 8 10 12 0 5 10 15 20 25 30 0 0

2 2

4 4

6 6 Depth (m)Depth 8 (m) Depth 8

10 10

12 12

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

29 2008 Lake System Health Monitoring Program Data Report

Hardup Lake

Municipality: Lake of Bays Watershed: Dwight Bay 2 2 Surface Area: 0.22 km Watershed Area (excluding lake): 0.72 km Maximum Depth: 16 m Cold Water Fishery? No Wetland Area: 18 % Secchi Depth (10-year average): 4.5 m Phosphorus (10-year average 1999-2008): 8.3 g/L Sensitivity: Moderate

May 2008 August 2008

0 5 10 15 20 0 5 10 15 20 25 0 0

5 5

10 10

15 15 Depth (m) Depth Depth (m) Depth

20 20

25 25

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

30 2008 Lake System Health Monitoring Program Data Report

High Lake

Municipality: Muskoka Lakes Watershed: Lake Rosseau 2 2 Surface Area: 0.64 km Watershed Area (excluding lake): 1.63 km Maximum Depth: 15 m Cold Water Fishery? No Wetland Area: 15 % Secchi Depth (10-year average): 7.1 m Phosphorus (10-year average 1999-2008): 6.3 g/L Sensitivity: Moderate (OT)

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0 2 2 4 4 6 6 8 8

Depth (m) Depth 10

Depth (m) Depth 10 12 12 14 14 16 16

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

31 2008 Lake System Health Monitoring Program Data Report

Lake Joseph – Cox Bay

Municipality: Muskoka Lakes Watershed: Lake Joseph/Lake Rosseau 2 2 Surface Area: 1.84 km Watershed Area (excluding lake): 4.6 km Maximum Depth: 12 m Cold Water Fishery? Yes Wetland Area: 4.07 % Secchi Depth (10-year average): 5.5 m Phosphorus (10-year average 1999-2008): 5.5 g/L Sensitivity: Moderate (OT)

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0

2 2

4 4

6 6

8 8 Depth (m) Depth (m) Depth 10 10

12 12

14 14

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

32 2008 Lake System Health Monitoring Program Data Report

Lake Joseph – Joseph River

Municipality: Muskoka Lakes Watershed: Lake Joseph/Lake Rosseau 2 2 Surface Area: 1.37 km Watershed Area (excluding lake): 7.93 km Maximum Depth: 8 m Cold Water Fishery? Yes Wetland Area: 5.73 % Secchi Depth (10-year average): 3.8 m Phosphorus (10-year average 1999-2008): 8.5 g/L Sensitivity: Moderate

May 2008 August 2008

0 2 4 6 8 10 12 0 5 10 15 20 25 0 0 1 1 2 2 3 3 4 4 5 5

Depth (m) Depth 6 (m) Depth 6 7 7 8 8 9 9

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

33 2008 Lake System Health Monitoring Program Data Report

Lake Joseph – Little Lake Joseph

Municipality: Seguin Watershed: Lake Joseph 2 2 Surface Area: 2.8 km Watershed Area (excluding lake): 6.5 km Maximum Depth: 40 m Cold Water Fishery? Yes Wetland Area: 4.96 % Secchi Depth (10-year average): 4.9 m Phosphorus (10-year average 1999-2008): 5.9 g/L Sensitivity: Moderate

May 2008 August 2008

0 2 4 6 8 10 12 0 5 10 15 20 25 0 0 5 5 10 10 15 15 20 20

Depth (m)Depth 25

Depth (m) Depth 25 30 30 35 35 40 40

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

34 2008 Lake System Health Monitoring Program Data Report

Lake Joseph – Main

Municipality: Muskoka Lakes Watershed: Lake Joseph 2 2 Surface Area: 50.89 km Watershed Area (excluding lake): 55.0 km Maximum Depth: 60 m Cold Water Fishery? Yes Wetland Area: 5 % Secchi Depth (10-year average): 6.5 m Phosphorus (10-year average 1999-2008): 4.9 g/L Sensitivity: High

May 2008 August 2008

0 5 10 15 0 5 10 15 20 25 0 0 10 10

20 20

30 30

40 40 Depth (m) Depth Depth (m) Depth 50 50

60 60

70 70

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

35 2008 Lake System Health Monitoring Program Data Report

Kahshe Lake – Grant’s Bay

Municipality: Gravenhurst Watershed: Sparrow Lake 2 2 Surface Area: 8.3 km Watershed Area (excluding lake): 32.7 km Maximum Depth: 20 m Cold Water Fishery? No Wetland Area: 5 % Secchi Depth (10-year average): 2.9 m Phosphorus (10-year average 1999-2008): 17.0 g/L Sensitivity: Moderate

May 2008 August 2008

0 5 10 15 20 0 5 10 15 20 25 0 0 1 1 2 2 3 3 4 4 5 5 6 6 Depth (m) Depth Depth (m)Depth 7 7 8 8 9 9 10 10

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

36 2008 Lake System Health Monitoring Program Data Report

Kahshe Lake – Main

Municipality: Gravenhurst Watershed: Sparrow Lake 2 2 Surface Area: 8.3 km Watershed Area (excluding lake): 32.7 km Maximum Depth: 20 m Cold Water Fishery? No Wetland Area: 5 % Secchi Depth (10-year average): 2.9 m Phosphorus (10-year average 1999-2008): 13.0 g/L Sensitivity: Moderate

May 2008 August 2008

0 5 10 15 20 0 5 10 15 20 25 30 0 0

5 5

10 10

15 15 Depth (m) Depth Depth (m) Depth

20 20

25 25

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

37 2008 Lake System Health Monitoring Program Data Report

Leech Lake

Municipality: Bracebridge Watershed: Muskoka River 2 2 Surface Area: 0.81 km Watershed Area (excluding lake): 3.41 km Maximum Depth: 13 m Cold Water Fishery? No Wetland Area: 10 % Secchi Depth (10-year average): 3.3 m Phosphorus (10-year average 1999-2008): 9.3 g/L Sensitivity: Moderate (OT)

May 2008 August 2008 0 5 10 15 20 0 5 10 15 20 25 0 0 2 2 4 4 6 6 8 8

Depth (m) Depth 10

Depth (m) Depth 10 12 12 14 14 16 16

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

38 2008 Lake System Health Monitoring Program Data Report

Little Long (Rutter) Lake

Municipality: Muskoka Lakes Watershed: Lake Rosseau 2 2 Surface Area: 0.22 km Watershed Area (excluding lake): 1.14 km Maximum Depth: 14 m Cold Water Fishery? No Wetland Area: 5 % Secchi Depth (10-year average): 4.4 m Phosphorus (10-year average 1999-2008): 7.7 g/L Sensitivity: Moderate (OT)

May 2008 August 2008 0 5 10 15 20 0 5 10 15 20 25 0 0 2 2 4 4 6 6

8 8 Depth (m) Depth 10 (m) Depth 10 12 12 14 14 16 16

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

39 2008 Lake System Health Monitoring Program Data Report

Long Lake

Municipality: Muskoka Lakes Watershed: Lake Muskoka 2 2 Surface Area: 1.31 km Watershed Area (excluding lake): 2.89 km Maximum Depth: 17 m Cold Water Fishery? No Wetland Area: 5.92 % Secchi Depth (10-year average): 4.9 m Phosphorus (10-year average 1999-2008): 6.6 g/L Sensitivity: High (OT)

May 2008 August 2008 0 5 10 15 20 0 5 10 15 20 25 0 0 2 2 4 4 6 6 8 8

Depth (m)Depth 10

Depth (m) Depth 10 12 12 14 14 16 16

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

40 2008 Lake System Health Monitoring Program Data Report

Long’s Lake

Municipality: Huntsville Watershed: Lake Rosseau 2 2 Surface Area: 0.43 km Watershed Area (excluding lake): 12.27 km Maximum Depth: 10 m Cold Water Fishery? No Wetland Area: 5 % Secchi Depth (10-year average): 2.3 m Phosphorus (10-year average 1999-2008): 9.0 g/L Sensitivity: Moderate

May 2008 August 2008

0 5 10 15 20 0 5 10 15 20 25 0 0 1 1 2 2 3 3 4 4 5 5 6 6 Depth (m) Depth (m) Depth 7 7 8 8 9 9 10 10

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

41 2008 Lake System Health Monitoring Program Data Report

Loon Lake

Municipality: Gravenhurst Watershed: Morrison Lake 2 2 Surface Area: 0.82 km Watershed Area (excluding lake): 8.18 km Maximum Depth: 5 m Cold Water Fishery? No Wetland Area: 10 % Secchi Depth (10-year average): 3.1 m Phosphorus (10-year average 1999-2008): 13.0 g/L Sensitivity: Moderate (OT)

May 2008 August 2008 9.8 9.9 10 10.1 10.2 10.3 10.4 10.5 0 5 10 15 20 25 0 0 0.5 0.5 1 1 1.5 1.5 2 2 2.5 2.5

Depth (m) Depth 3 (m) Depth 3 3.5 3.5 4 4 4.5 4.5

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

42 2008 Lake System Health Monitoring Program Data Report

McCrae Lake

Municipality: Georgian Bay Watershed: West 2 2 Surface Area: 2.35 km Watershed Area (excluding lake): 7.85 km Maximum Depth: 16 m Cold Water Fishery? No Wetland Area: 1.92 % Secchi Depth (10-year average): 4.5 m Phosphorus (10-year average 1999-2008): 8.9 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 20 0 5 10 15 20 25 30 0 0 2 2 4 4 6 6 8 8 10 10

Depth (m) Depth 12 (m) Depth 12 14 14 16 16 18 18

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

43 2008 Lake System Health Monitoring Program Data Report

McDonald Lake

Municipality: Georgian Bay Watershed: West 2 2 Surface Area: 0.2 km Watershed Area (excluding lake): 2.76 km Maximum Depth: 16 m Cold Water Fishery? No Wetland Area: 6.09 % Secchi Depth (10-year average): 5.0 m Phosphorus (10-year average 1999-2008): 10.1 g/L Sensitivity: Moderate

May 2008 August 2008

0 5 10 15 20 0 5 10 15 20 25 0 0 2 2 4 4 6 6 8 8

Depth (m) Depth 10 (m) Depth 10 12 12 14 14 16 16

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

44 2008 Lake System Health Monitoring Program Data Report

McKay Lake

Municipality: Bracebridge Watershed: Muskoka River 2 2 Surface Area: 1.34 km Watershed Area (excluding lake): 6.86 km Maximum Depth: 19 m Cold Water Fishery? No Wetland Area: 10 % Secchi Depth (10-year average): 3.2 m Phosphorus (10-year average 1999-2008): 9.3 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0 2 2 4 4 6 6 8 8 10 10 Depth (m) Depth 12 (m) Depth 12 14 14 16 16 18 18

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

45 2008 Lake System Health Monitoring Program Data Report

Medora Lake

Municipality: Muskoka Lakes Watershed: Lake Muskoka 2 2 Surface Area: 0.41 km Watershed Area (excluding lake): 2.25 km Maximum Depth: 9 m Cold Water Fishery? No Wetland Area: 5 % Secchi Depth (10-year average): 3.9 m Phosphorus (10-year average 1999-2008): 8.4 g/L Sensitivity: Moderate (OT)

May 2008 August 2008

0 5 10 15 0 5 10 15 20 25 0 0 1 1 2 2 3 3 4 4 5 5 Depth (m) Depth Depth (m) Depth 6 6 7 7 8 8 9 9

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

46 2008 Lake System Health Monitoring Program Data Report

Mirror Lake

Municipality: Muskoka Lakes Watershed: Lake Muskoka 2 2 Surface Area: 0.46 km Watershed Area (excluding lake): 0.97 km Maximum Depth: 8 m Cold Water Fishery? No Wetland Area: 20 % Secchi Depth (10-year average): 3.6 m Phosphorus (10-year average 1999-2008): 7.3 g/L Sensitivity: Moderate (OT)

May 2008 August 2008

0 5 10 15 0 5 10 15 20 25 0 0 1 1 2 2

3 3

4 4

Depth (m) Depth (m) Depth 5 5

6 6

7 7

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

47 2008 Lake System Health Monitoring Program Data Report

Moot Lake

Municipality: Lake of Bays Watershed: Muskoka River 2 2 Surface Area: 0.49 km Watershed Area (excluding lake): 5.06 km Maximum Depth: 7 m Cold Water Fishery? No Wetland Area: 20 % Secchi Depth (10-year average): 1.7 m Phosphorus (10-year average 1999-2008): 15.5 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 20 0 5 10 15 20 25 0 0

1 1

2 2

3 3

4 4 Depth (m)Depth Depth (m) Depth 5 5

6 6

7 7

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

48 2008 Lake System Health Monitoring Program Data Report

Lake Muskoka – Bala Bay

Municipality: Muskoka Lakes Watershed: Lake Muskoka 2 2 Surface Area: 4.3 km Watershed Area (excluding lake): 4.85 km Maximum Depth: 38 m Cold Water Fishery? Yes Wetland Area: 10.87 % Secchi Depth (10-year average): 4.2 m Phosphorus (10-year average 1999-2008): 6.1 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0 5 5 10 10 15 15 20 20

Depth (m)Depth 25

Depth (m) Depth 25 30 30 35 35 40 40

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

49 2008 Lake System Health Monitoring Program Data Report

Lake Muskoka – Dudley Bay

Municipality: Muskoka Lakes Watershed: Lake Muskoka 2 2 Surface Area: 3.6 km Watershed Area (excluding lake): 12.6 km Maximum Depth: 20 m Cold Water Fishery? Yes Wetland Area: 5 % Secchi Depth (10-year average): 4.1 m Phosphorus (10-year average 1999-2008): 6.1 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0 2 2 4 4 6 6 8 8

10 10 Depth (m) Depth 12 (m) Depth 12 14 14 16 16 18 18

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

50 2008 Lake System Health Monitoring Program Data Report

Lake Muskoka – Main

Municipality: Muskoka Lakes Watershed: Lake Muskoka 2 2 Surface Area: 62 km Watershed Area (excluding lake): 73 km Maximum Depth: 47 m Cold Water Fishery? Yes Wetland Area: 10 % Secchi Depth (10-year average): 4.2 m Phosphorus (10-year average 1999-2008): 5.6 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0

10 10

20 20

30 30

40 40

Depth (m)Depth Depth (m) Depth 50 50

60 60

70 70

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

51 2008 Lake System Health Monitoring Program Data Report

Lake Muskoka – Muskoka Bay

Municipality: Gravenhurst Watershed: Lake Muskoka 2 2 Surface Area: 4.1 km Watershed Area (excluding lake): 20.4 km Maximum Depth: 14 m Cold Water Fishery? Yes Wetland Area: 9.41 % Secchi Depth (10-year average): 3.3 m Phosphorus (10-year average 1999-2008): 11.7 g/L Sensitivity: Moderate (OT)

May 2008 August 2008

0 5 10 15 20 0 5 10 15 20 25 0 0 2 2 4 4 6 6 8 8

Depth (m) Depth 10 (m) Depth 10 12 12 14 14 16 16

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

52 2008 Lake System Health Monitoring Program Data Report

Lake Muskoka – Whiteside Bay

Municipality: Muskoka Lakes Watershed: Lake Muskoka 2 2 Surface Area: 1.14 km Watershed Area (excluding lake): 7.46 km Maximum Depth: 18 m Cold Water Fishery? Yes Wetland Area: 16.74 % Secchi Depth (10-year average): 4.3 m Phosphorus (10-year average 1999-2008): 6.1 g/L Sensitivity: Low

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0 2 2 4 4 6 6 8 8

Depth (m) Depth 10 (m) Depth 10 12 12 14 14 16 16

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

53 2008 Lake System Health Monitoring Program Data Report

Neilson Lake

Municipality: Muskoka Lakes Watershed: Lake Muskoka 2 2 Surface Area: 0.17 km Watershed Area (excluding lake): 6.23 km Maximum Depth: 10 m Cold Water Fishery? No Wetland Area: 20 % Secchi Depth (10-year average): 2.4 m Phosphorus (10-year average 1999-2008): 14.8 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 20 0 5 10 15 20 25 0 0

2 2

4 4

6 6

Depth (m) Depth 8 (m) Depth 8

10 10

12 12

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

54 2008 Lake System Health Monitoring Program Data Report

North Bay

Municipality: Georgian Bay Watershed: West 2 2 Surface Area: 2 km Watershed Area (excluding lake): 9 km Maximum Depth: 19 m Cold Water Fishery? Yes Wetland Area: 22 % Secchi Depth (10-year average): 3.2 m Phosphorus (10-year average 1999-2008): 11.9 g/L Sensitivity: Low

May 2008 August 2008 0 5 10 15 20 0 5 10 15 20 25 30 0 0 2 2 4 4 6 6 8 8 10 10 12 12 Depth (m) Depth (m) Depth 14 14 16 16 18 18 20 20

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

55 2008 Lake System Health Monitoring Program Data Report

North Muldrew Lake

Municipality: Gravenhurst Watershed: Morrison Lake 2 2 Surface Area: 1.52 km Watershed Area (excluding lake): 13.28 km Maximum Depth: 16 m Cold Water Fishery? No Wetland Area: 8 % Secchi Depth (10-year average): 2.8 m Phosphorus (10-year average 1999-2008): 10.6 g/L Sensitivity: Moderate

May 2008 August 2008 0 2 4 6 8 10 12 0 5 10 15 20 25 0 0 2 2 4 4 6 6 8 8

Depth (m) Depth 10 (m) Depth 10 12 12 14 14 16 16

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

56 2008 Lake System Health Monitoring Program Data Report

Penfold Lake

Municipality: Huntsville Watershed: Mary Lake 2 2 Surface Area: 0.34 km Watershed Area (excluding lake): 7.06 km Maximum Depth: 3 m Cold Water Fishery? No Wetland Area: 33 % Secchi Depth (10-year average): 1.8 m Phosphorus (10-year average 1999-2008): 16.9 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 20 0 5 10 15 20 25 0 0

0.5 0.5

1 1

1.5 1.5 Depth (m) Depth (m) Depth

2 2

2.5 2.5

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

57 2008 Lake System Health Monitoring Program Data Report

Peninsula Lake – East

Municipality: Lake of Bays Watershed: Mary Lake 2 2 Surface Area: 8.53 km Watershed Area (excluding lake): 35.17 km Maximum Depth: 32 m Cold Water Fishery? Yes Wetland Area: 15 % Secchi Depth (10-year average): 4.3 m Phosphorus (10-year average 1999-2008): 11.4 g/L Sensitivity: Moderate

May 2008 August 2008 0 2 4 6 8 10 12 0 5 10 15 20 25 0 0

5 5

10 10

15 15

Depth (m) Depth Depth (m) Depth

20 20

25 25

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

58 2008 Lake System Health Monitoring Program Data Report

Peninsula Lake – West

Municipality: Huntsville Watershed: Mary Lake 2 2 Surface Area: 8.53 km Watershed Area (excluding lake): 35.17 km Maximum Depth: 32 m Cold Water Fishery? Yes Wetland Area: 15 % Secchi Depth (10-year average): 4.4 m Phosphorus (10-year average 1999-2008): 10.6 g/L Sensitivity: Moderate

May 2008 August 2008 0 2 4 6 8 10 12 0 5 10 15 20 25 0 0 5 5 10 10 15 15

20 20 Depth (m) Depth 25 (m) Depth 25 30 30 35 35 40 40

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

59 2008 Lake System Health Monitoring Program Data Report

Pigeon Lake

Municipality: Gravenhurst Watershed: Lake Muskoka 2 2 Surface Area: 0.61 km Watershed Area (excluding lake): 2.19 km Maximum Depth: 6 m Cold Water Fishery? No Wetland Area: 6.16 % Secchi Depth (10-year average): 3.9 m Phosphorus (10-year average 1999-2008): 8.9 g/L Sensitivity: Moderate

May 2008 August 2008

0 5 10 15 20 0 5 10 15 20 25 30 0 0 1 1 2 2 3 3 4 4

Depth (m) Depth 5

Depth (m)Depth 5 6 6 7 7 8 8

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

60 2008 Lake System Health Monitoring Program Data Report

Porcupine Lake

Municipality: Lake of Bays Watershed: Black River 2 2 Surface Area: 0.57 km Watershed Area (excluding lake): 3.18 km Maximum Depth: 20 m Cold Water Fishery? No Wetland Area: 8.57 % Secchi Depth (10-year average): 3.2 m Phosphorus (10-year average 1999-2008): 7.4 g/L Sensitivity: Moderate

May 2008 August 2008

0 5 10 15 0 5 10 15 20 25 0 0

5 5

10 10

15 15 Depth (m)Depth Depth (m) Depth

20 20

25 25

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

61 2008 Lake System Health Monitoring Program Data Report

Rebecca Lake

Municipality: Lake of Bays Watershed: Lake Vernon 2 2 Surface Area: 2.15 km Watershed Area (excluding lake): 9.65 km Maximum Depth: 39 m Cold Water Fishery? Yes Wetland Area: 15 % Secchi Depth (10-year average): 4.2 m Phosphorus (10-year average 1999-2008): 5.7 g/L Sensitivity: Low

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0

5 5

10 10

15 15

Depth (m) Depth 20 (m) Depth 20

25 25

30 30

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

62 2008 Lake System Health Monitoring Program Data Report

Ril Lake

Municipality: Lake of Bays Watershed: Muskoka River 2 2 Surface Area: 1.45 km Watershed Area (excluding lake): 7.85 km Maximum Depth: 10 m Cold Water Fishery? No Wetland Area: 5 % Secchi Depth (10-year average): 3.1 m Phosphorus (10-year average 1999-2008): 10.5 g/L Sensitivity: Moderate (OT)

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0 1 1 2 2 3 3 4 4 5 5

6 6

Depth (m)Depth Depth (m) Depth 7 7 8 8 9 9 10 10

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

63 2008 Lake System Health Monitoring Program Data Report

Lake Rosseau – Brackenrig Bay

Municipality: Muskoka Lakes Watershed: Lake Rosseau 2 2 Surface Area: 0.44 km Watershed Area (excluding lake): 2.16 km Maximum Depth: 4 m Cold Water Fishery? Yes Wetland Area: 0 % Secchi Depth (10-year average): 3.0 m Phosphorus (10-year average 1999-2008): 8.1 g/L Sensitivity: Moderate (OT)

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0 0.5 0.5 1 1 1.5 1.5 2 2 2.5 2.5

Depth (m) Depth 3 (m)Depth 3 3.5 3.5 4 4 4.5 4.5

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

64 2008 Lake System Health Monitoring Program Data Report

Lake Rosseau – East Portage Bay

Municipality: Muskoka Lakes Watershed: Lake Rosseau 2 2 Surface Area: 1.33 km Watershed Area (excluding lake): 3.17 km Maximum Depth: 12 m Cold Water Fishery? Yes Wetland Area: 0 % Secchi Depth (10-year average): 4.6 m Phosphorus (10-year average 1999-2008): 7.1 g/L Sensitivity: High (OT)

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0

2 2

4 4

6 6

8 8 Depth (m) Depth Depth (m)Depth 10 10

12 12

14 14

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

65 2008 Lake System Health Monitoring Program Data Report

Lake Rosseau – Main

Municipality: Muskoka Lakes Watershed: Lake Rosseau 2 2 Surface Area: 55.5 km Watershed Area (excluding lake): 204.5 km Maximum Depth: 60 m Cold Water Fishery? Yes Wetland Area: 5 % Secchi Depth (10-year average): 5.6 m Phosphorus (10-year average 1999-2008): 5.7 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25

0 0 10 5 10 20 15 30 20 40 25 Depth (m) Depth Depth (m) Depth 30 50 35 60 40 70 45

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

66 2008 Lake System Health Monitoring Program Data Report

Lake Rosseau – North

Municipality: Muskoka Lakes/Seguin Watershed: Lake Rosseau 2 2 Surface Area: 55.5 km Watershed Area (excluding lake): 204.5 km Maximum Depth: 75 m Cold Water Fishery? Yes Wetland Area: 5 % Secchi Depth (10-year average): 5.1 m Phosphorus (10-year average 1999-2008): 6.8 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0

10 10

20 20

30 30

40 40 Depth (m) Depth Depth (m) Depth 50 50

60 60

70 70

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

67 2008 Lake System Health Monitoring Program Data Report

Lake Rosseau – Skeleton Bay

Municipality: Muskoka Lakes Watershed: Lake Rosseau 2 2 Surface Area: 1.71 km Watershed Area (excluding lake): 15.89 km Maximum Depth: 20 m Cold Water Fishery? Yes Wetland Area: 3.76 % Secchi Depth (10-year average): 4.8 m Phosphorus (10-year average 1999-2008): 6.5 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0

5 5

10 10

15 15 Depth (m) Depth Depth (m) Depth

20 20

25 25

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

68 2008 Lake System Health Monitoring Program Data Report

Sixteen Mile Lake

Municipality: Lake of Bays Watershed: Dwight Bay 2 2 Surface Area: 0.8 km Watershed Area (excluding lake): 4.55 km Maximum Depth: 10 m Cold Water Fishery? No Wetland Area: 23.41 % Secchi Depth (10-year average): 3.8 m Phosphorus (10-year average 1999-2008): 7.9 g/L Sensitivity: Moderate

May 2008 August 2008

0 5 10 15 20 0 5 10 15 20 25 0 0 2 2

4 4

6 6 Depth (m) Depth Depth (m) Depth 8 8

10 10

12 12

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

69 2008 Lake System Health Monitoring Program Data Report

Skeleton Lake

Municipality: Muskoka Lakes Watershed: Lake Rosseau 2 2 Surface Area: 21 km Watershed Area (excluding lake): 44.5 km Maximum Depth: 60 m Cold Water Fishery? Yes Wetland Area: 10 % Secchi Depth (10-year average): 9.8 m Phosphorus (10-year average 1999-2008): 4.1 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0

10 10

20 20

30 30

40 40

Depth (m) Depth Depth (m)Depth 50 50

60 60

70 70

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

70 2008 Lake System Health Monitoring Program Data Report

South Bay

Municipality: Georgian Bay Watershed: West 2 2 Surface Area: 1.61 km Watershed Area (excluding lake): 12.19 km Maximum Depth: 11 m Cold Water Fishery? Yes Wetland Area: 20 % Secchi Depth (10-year average): 3.7 m Phosphorus (10-year average 1999-2008): 12.2 g/L Sensitivity: Moderate (OT)

May 2008 August 2008

0 5 10 15 20 0 5 10 15 20 25 30 0 0

2 2

4 4

6 6 Depth (m) Depth 8 (m)Depth 8

10 10

12 12

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

71 2008 Lake System Health Monitoring Program Data Report

South Muldrew Lake

Municipality: Gravenhurst Watershed: Morrison Lake 2 2 Surface Area: 2.7 km Watershed Area (excluding lake): 13.3 km Maximum Depth: 18 m Cold Water Fishery? No Wetland Area: 6.62 % Secchi Depth (10-year average): 2.8 m Phosphorus (10-year average 1999-2008): 8.5 g/L Sensitivity: Moderate

May 2008 August 2008 0 2 4 6 8 10 12 0 5 10 15 20 25 0 0 2 2 4 4 6 6 8 8 10 10 Depth (m) Depth Depth (m) Depth 12 12 14 14 16 16 18 18

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

72 2008 Lake System Health Monitoring Program Data Report

South Nelson Lake

Municipality: Lake of Bays Watershed: Dwight Bay 2 2 Surface Area: 0.15 km Watershed Area (excluding lake): 2.84 km Maximum Depth: 6 m Cold Water Fishery? No Wetland Area: 6.2 % Secchi Depth (10-year average): 3.0 m Phosphorus (10-year average 1999-2008): 8.5 g/L Sensitivity: Moderate

May 2008 August 2008

0 5 10 15 20 0 5 10 15 20 25 0 0

1 1

2 2

3 3 Depth (m) Depth 4 (m) Depth 4

5 5

6 6

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

73 2008 Lake System Health Monitoring Program Data Report

Sparrow Lake

Municipality: Gravenhurst Watershed: Sparrow Lake 2 2 Surface Area: 10.35 km Watershed Area (excluding lake): 120.65 km Maximum Depth: 16 m Cold Water Fishery? No Wetland Area: 6.62 % Secchi Depth (10-year average): 3.7 m Phosphorus (10-year average 1999-2008): 11.3 g/L Sensitivity: Moderate

May 2008 August 2008

0 5 10 15 20 0 5 10 15 20 25 0 0

2 2

4 4

6 6

8 8 Depth (m) Depth Depth (m)Depth 10 10

12 12

14 14

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

74 2008 Lake System Health Monitoring Program Data Report

Spring Lake

Municipality: Bracebridge Watershed: Muskoka River 2 2 Surface Area: 0.28 km Watershed Area (excluding lake): 1.09 km Maximum Depth: 20 m Cold Water Fishery? No Wetland Area: 2.67 % Secchi Depth (10-year average): 4.7 m Phosphorus (10-year average 1999-2008): 7.1 g/L Sensitivity: Moderate (OT)

May 2008 August 2008 0 5 10 15 20 0 5 10 15 20 25 0 0 2 2 4 4 6 6 8 8 10 10 12 12 Depth (m) Depth Depth (m)Depth 14 14 16 16 18 18 20 20

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

75 2008 Lake System Health Monitoring Program Data Report

Stewart Lake

Municipality: Muskoka Lakes Watershed: Lake Joseph 2 2 Surface Area: 1.55 km Watershed Area (excluding lake): 9.25 km Maximum Depth: 19 m Cold Water Fishery? No Wetland Area: 6.56 % Secchi Depth (10-year average): 3.3 m Phosphorus (10-year average 1999-2008): 7.8 g/L Sensitivity: Moderate (OT)

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0 2 2 4 4 6 6 8 8 10 10

12 12

Depth (m) Depth Depth (m) Depth 14 14 16 16 18 18 20 20

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

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Stoneleigh Lake

Municipality: Bracebridge Watershed: Muskoka River 2 2 Surface Area: 0.54 km Watershed Area (excluding lake): 6.19 km Maximum Depth: 5 m Cold Water Fishery? No Wetland Area: 29 % Secchi Depth (10-year average): 1.5 m Phosphorus (10-year average 1999-2008): 12.9 g/L Sensitivity: Moderate

May 2008 August 2008

0 5 10 15 20 0 5 10 15 20 25 0 0 0.5 0.5 1 1 1.5 1.5 2 2 2.5 2.5 Depth (m)Depth Depth (m) Depth 3 3 3.5 3.5 4 4 4.5 4.5

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

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Tackaberry Lake

Municipality: Lake of Bays Watershed: Muskoka River 2 2 Surface Area: 0.11 km Watershed Area (excluding lake): 0.59 km Maximum Depth: 12 m Cold Water Fishery? No Wetland Area: 0 % Secchi Depth (10-year average): 5.2 m Phosphorus (10-year average 1999-2008): 6.2 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 20 0 5 10 15 20 25 0 0 1 1 2 2 3 3 4 4 5 5 Depth (m) Depth 6 (m)Depth 6 7 7 8 8 9 9

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

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Three Mile Lake

Municipality: Gravenhurst Watershed: Sparrow Lake 2 2 Surface Area: 0.85 km Watershed Area (excluding lake): 5.75 km Maximum Depth: 8 m Cold Water Fishery? No Wetland Area: 11 % Secchi Depth (10-year average): 3.9 m Phosphorus (10-year average 1999-2008): 6.9 g/L Sensitivity: Moderate

May 2008 August 2008

0 5 10 15 20 0 5 10 15 20 25 0 0 1 1 2 2 3 3 4 4 5 5 Depth (m) Depth 6 (m) Depth 6 7 7 8 8 9 9

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

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Three Mile Lake – Hammel’s Bay

Municipality: Muskoka Lakes Watershed: Lake Rosseau 2 2 Surface Area: 2.3 km Watershed Area (excluding lake): 13.2 km Maximum Depth: 12 m Cold Water Fishery? No Wetland Area: 15 % Secchi Depth (10-year average): 2.8 m Phosphorus (10-year average 1999-2008): 15.7 g/L Sensitivity: Moderate (OT)

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0

2 2

4 4

6 6 Depth (m) Depth 8 (m) Depth 8

10 10

12 12

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

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Three Mile Lake – Main

Municipality: Muskoka Lakes Watershed: Lake Rosseau 2 2 Surface Area: 6.4 km Watershed Area (excluding lake): 107.6 km Maximum Depth: 4 m Cold Water Fishery? No Wetland Area: 20 % Secchi Depth (10-year average): 1.4 m Phosphorus (10-year average 1999-2008): 24.0 g/L Sensitivity: Moderate (OT)

May 2008 August 2008 0 5 10 15 20 0 5 10 15 20 25 0 0 0.5 0.5 1 1 1.5 1.5 2 2

2.5 2.5 Depth (m) Depth 3 (m) Depth 3 3.5 3.5 4 4 4.5 4.5

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

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Tooke Lake

Municipality: Lake of Bays Watershed: Lake of Bays 2 2 Surface Area: 0.33 km Watershed Area (excluding lake): 0.55 km Maximum Depth: 6 m Cold Water Fishery? No Wetland Area: 10 % Secchi Depth (10-year average): 5.0 m Phosphorus (10-year average 1999-2008): 5.7 g/L Sensitivity: Moderate (OT)

May 2008 August 2008

0 5 10 15 20 0 5 10 15 20 25 0 0

1 1

2 2

3 3 Depth (m) Depth 4 (m) Depth 4

5 5

6 6

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

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Twelve Mile Bay – East

Municipality: Georgian Bay Watershed: West 2 2 Surface Area: 2.3 km Watershed Area (excluding lake): 26.7 km Maximum Depth: 28 m Cold Water Fishery? Yes Wetland Area: 4.87 % Secchi Depth (10-year average): 3.2 m Phosphorus (10-year average 1999-2008): 11.2 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 0 5 10 15 20 25 0 0

5 5

10 10

15 15 Depth (m) Depth 20 (m) Depth 20

25 25

30 30

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

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Twelve Mile Bay – West

Municipality: Georgian Bay Watershed: West 2 2 Surface Area: 2.3 km Watershed Area (excluding lake): 26.7 km Maximum Depth: 28 m Cold Water Fishery? Yes Wetland Area: 4.87 % Secchi Depth (10-year average): 9.1 m Phosphorus (10-year average 1999-2008): 5.8 g/L Sensitivity: Moderate

May 2008 August 2008 0 5 10 15 20 0 5 10 15 20 25 30 0 0

2 2

4 4

6 6 Depth (m) Depth 8 (m)Depth 8

10 10

12 12

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

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Lake Vernon – Hunter’s Bay

Municipality: Huntsville Watershed: Lake Vernon 2 2 Surface Area: 0.81 km Watershed Area (excluding lake): 5.77 km Maximum Depth: 9 m Cold Water Fishery? Yes Wetland Area: 21.72 % Secchi Depth (10-year average): 2.6 m Phosphorus (10-year average 1999-2008): 10.2 g/L Sensitivity: Moderate

May 2008 August 2008

0 5 10 15 0 5 10 15 20 0 0 1 1 2 2 3 3 4 4 5 5 Depth (m) Depth 6 (m) Depth 6 7 7 8 8 9 9

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

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Lake Vernon – Main

Municipality: Huntsville Watershed: Lake Vernon 2 2 Surface Area: 13.8 km Watershed Area (excluding lake): 94.7 km Maximum Depth: 38 m Cold Water Fishery? Yes Wetland Area: 5 % Secchi Depth (10-year average): 2.8 m Phosphorus (10-year average 1999-2008): 9.3 g/L Sensitivity: Moderate

May 2008 August 2008

0 2 4 6 8 10 12 0 5 10 15 20 0 0 5 5 10 10 15 15

20 20 Depth (m) Depth 25 (m) Depth 25 30 30 35 35 40 40

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

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Lake Vernon – North Bay

Municipality: Huntsville Watershed: Lake Vernon 2 2 Surface Area: 0.9 km Watershed Area (excluding lake): 18.6 km Maximum Depth: 36 m Cold Water Fishery? Yes Wetland Area: 0 % Secchi Depth (10-year average): 2.7 m Phosphorus (10-year average 1999-2008): 10.0 g/L Sensitivity: Moderate

May 2008 August 2008

0 2 4 6 8 10 12 0 5 10 15 20 0 0

5 5

10 10

15

Depth (m) Depth 15 Depth (m) Depth

20 20

25 25

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

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Walker Lake

Municipality: Lake of Bays Watershed: Mary Lake 2 2 Surface Area: 0.7 km Watershed Area (excluding lake): 2.72 km Maximum Depth: 16 m Cold Water Fishery? No Wetland Area: 5 % Secchi Depth (10-year average): 5.4 m Phosphorus (10-year average 1999-2008): 6.8 g/L Sensitivity: Moderate (OT)

May 2008 August 2008

0 2 4 6 8 10 12 0 5 10 15 20 25 0 0 2 2 4 4 6 6 8 8

10 10 Depth (m) Depth 12 (m) Depth 12 14 14 16 16 18 18

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

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Young Lake

Municipality: Muskoka Lakes Watershed: Lake Rosseau 2 2 Surface Area: 1.1 km Watershed Area (excluding lake): 4.8 km Maximum Depth: 22 m Cold Water Fishery? Yes Wetland Area: 4.22 % Secchi Depth (10-year average): 4.3 m Phosphorus (10-year average 1999-2008): 11.5 g/L Sensitivity: Moderate

May 2008 August 2008

0 5 10 15 20 0 5 10 15 20 25 30 0 0

5 5

10 10

15 15 Depth (m) Depth Depth (m) Depth

20 20

25 25

Temperature (°C) Dissolved Oxygen (mg/L) Temperature (°C) Dissolved Oxygen (mg/L)

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2008 Lake Joseph Monitoring Data

The District Municipality of Muskoka

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Lake Joseph – Sampling Points

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Lake Joseph – Cox Bay

Temperature (°C) Dissolved Oxygen (mg/L)

0 5 10 15 20 25 30 0 2 4 6 8 10 12 14 0 0

2 2

4 4 8-May 22-May 6 6 4-Jun 18-Jun 8 8 Depth (m) Depth 2-Jul 15-Jul 10 10 29-Jul

12 12 14-Aug 28-Aug 14 14

8.0

7.0

6.0

5.0

4.0

3.0

2.0

1.0

0.0

8-May 22-May 4-Jun 18-Jun 2-Jul 15-Jul 29-Jul 14-Aug 27-Aug Ave Phosphorus (µg/L) 6.6 4.7 4.6 7.6 7.1 6.3 5.2 6.8 6.0 Secchi Depth (m) 3.9 4.5 5.0 6.1 5.1 4.0 4.0 5.9 6.2

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Lake Joseph – Hamer Bay

Temperature (°C) Dissolved Oxygen (mg/L) 0 5 10 15 20 25 0 2 4 6 8 10 12 14 0 0 5 5 10 10

15 8-May 15 20 22-May 20 4-Jun 25 25 18-Jun

Depth (m) Depth 30 2-Jul 30 35 15-Jul 35 29-Jul 40 40 14-Aug 45 28-Aug 45 50 50

7.0

6.0

5.0

4.0

3.0

2.0

1.0

0.0

8-May 22-May 4-Jun 18-Jun 2-Jul 15-Jul 29-Jul 14-Aug 27-Aug Ave Phosphorus (µg/L) 4.1 4.7 4.0 4.9 2.9 3.1 4.2 5.8 2.8 Secchi Depth (m) 6.1 5.5 5.0 5.1 6.1 5.4 4.4 5.1 5.9

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Lake Joseph – Joseph River

Temperature (°C) Dissolved Oxygen (mg/L) 0 5 10 15 20 25 30 0 2 4 6 8 10 12 14 0 0 8-May 1 1 22-May 4-Jun 2 2 18-Jun 2-Jul 3 3 15-Jul 29-Jul 4 4 14-Aug

5 5 28-Aug Depth (m) Depth 6 6

7 7

8 8

9 9

16.0

14.0

12.0

10.0

8.0

6.0

4.0

2.0

0.0

8-May 22-May 4-Jun 18-Jun 2-Jul 15-Jul 29-Jul 14-Aug 27-Aug Ave Phosphorus (µg/L) 7.1 9.1 10.3 11.7 13.5 11.8 12.5 11.8 11.7 Secchi Depth (m) 3.0 3.3 3.8 4.1 4.4 3.6 2.9 3.7 4.0

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Lake Joseph – Little Lake Joseph

Temperature (°C) Dissolved Oxygen (mg/L) 0 5 10 15 20 25 0 2 4 6 8 10 12 0 0 8-May 5 5 22-May 10 10 4-Jun 18-Jun 15 15 2-Jul 20 20 15-Jul 25 25 29-Jul

Depth (m) Depth 14-Aug 30 30 28-Aug 35 35

40 40

45 45

8.0

7.0

6.0

5.0

4.0

3.0

2.0

1.0

0.0

8-May 22-May 4-Jun 18-Jun 2-Jul 15-Jul 29-Jul 14-Aug 27-Aug Ave Phosphorus (µg/L) 6.8 7.4 7.5 6.5 5.9 7.6 6.4 5.0 4.1 Secchi Depth (m) 3.5 3.3 3.9 4.5 4.8 4.2 5.0 5.0 4.8

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Lake Joseph – Main

Temperature (°C) Dissolved Oxygen (mg/L) 0 5 10 15 20 25 0 2 4 6 8 10 12 14 0 0

10 10

20 20 8-May 22-May 30 30 4-Jun 40 40 18-Jun Depth (m) Depth 2-Jul 50 50 15-Jul 29-Jul 60 60 14-Aug 28-Aug 70 70

7.0

6.0

5.0

4.0

3.0

2.0

1.0

0.0

8-May 22-May 4-Jun 18-Jun 2-Jul 15-Jul 29-Jul 14-Aug 27-Aug Ave Phosphorus (µg/L) 4.7 4.5 5.2 3.8 2.6 3.6 4.3 4.0 2.6 Secchi Depth (m) 4.0 4.8 4.8 4.8 4.6 4.7 5.0 6.0 6.1

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Lake Joseph – North

Temperature (°C) Dissolved Oxygen (mg/L) 0 5 10 15 20 25 0 2 4 6 8 10 12 14 0 0 10 10

20 20 8-May 22-May 30 30 4-Jun 18-Jun 40 40 Depth (m) Depth 2-Jul

50 50 15-Jul 29-Jul 60 60 14-Aug 28-Aug 70 70

9.0

8.0

7.0

6.0

5.0

4.0

3.0

2.0

1.0

0.0

8-May 22-May 4-Jun 18-Jun 2-Jul 15-Jul 29-Jul 14-Aug 27-Aug Ave Phosphorus (µg/L) 4.7 5.0 8.1 4.6 4.0 3.2 4.3 4.2 2.4 Secchi Depth (m) 6.0 5.7 5.0 5.6 6.0 5.3 5.5 5.6 5.8

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Lake Joseph - South

Temperature (°C) Dissolved Oxygen (mg/L)

0 5 10 15 20 25 0 5 10 15 0 0 8-May 5 5 22-May 4-Jun 10 10 18-Jun 15 15 3-Jul 15-Jul 20 20 29-Jul Depth (m) Depth 25 25 14-Aug 28-Aug 30 30

35 35

40 40

8.0

7.0

6.0

5.0

4.0

3.0

2.0

1.0

0.0

8-May 22-May 4-Jun 18-Jun 2-Jul 15-Jul 29-Jul 14-Aug 27-Aug Ave Phosphorus (µg/L) 4.9 4.9 4.5 3.7 3.6 5.0 5.5 5.1 2.9 Secchi Depth (m) 5.0 4.8 6.0 5.9 5.1 4.8 4.3 6.7 5.9

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2008 Land Use Survey Data Tables

The District Municipality of Muskoka

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Lake Joseph – Muskoka Portion

Shoreline Backlot Structures

Type Length (m) Percent Type Area (m2) Percent Type Count Natural Beach 383.26 0.29 Commercial 9,423.71 0.38 Crib Boathouse 19 Beaver Lodge 16.46 0.01 Farm 7,811.01 0.31 1 Slip Crib Boathouse 167 Rock 78,364.32 58.89 Natural Beach 1,770.18 0.07 2 Slip Crib Boathouse 244 Rapids/Falls 23.81 0.02 Coniferous Forest 5,421.87 0.22 3 Slip Crib Boathouse 110 Shrub 40,173.67 30.19 Mixed Forest 1,414,705.68 56.42 3+ Slip Crib Boathouse 24 Wetland 688.35 0.52 Thinned Forest 484,174.49 19.31 1 Slip Fill Boathouse 1 Man Made Beach 1,143.54 0.86 Overgrowth 34,425.10 1.37 Boathouse on Land 9 Road 50.87 0.04 Rock 78,167.28 3.12 1 Slip Pole Boathouse 2 Concrete Ramp 37.69 0.03 Rock Barren 809.20 0.03 2 Slip Pole Boathouse 3 Stone/Gravel Ramp 52.48 0.04 Rapids/Falls 2,576.90 0.10 3 Slip Pole Boathouse 5 Wooden Ramp 6.13 0.00 Shrub 1,060.92 0.04 3+ Slip Pole Boathouse 2 Concrete Shore Wall 843.29 0.63 Wetland 4,100.00 0.16 Crib Dock 470 Stone Shore Wall 7,885.41 5.93 Man Made Beach 588.32 0.02 1 Slip Crib Dock 87 Wooden Shore Wall 1,129.96 0.85 Road 17,194.17 0.69 2 Slip Crib Dock 40 Unbuffered Lawn 2,269.94 1.71 Cottage 594.78 0.02 Fill Dock 15 Landscaped Yard 181,077.61 7.22 Floating Dock 32 Buffered Lawn 122,682.39 4.89 Pole Dock 33 Unbuffered Lawn 140,977.66 5.62 Marine Railway 4 Bridge 16 Cottage 2 Deck 24 Sleep Cabin 7 Pump House 6 Airplane Hanger 1 Wooden Ramp 31 Other 16

Total 133,069.18 100.00 Total 2,507,561.27 100.00 Total 1,370 Natural 119,649.87 89.92 Natural 1,508,612.03 60.16

Altered 13,419.31 10.08 Altered 998,949.24 39.84

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Mary Lake

Shoreline Backlot Structures

Type Length (m) Percent Type Area (m2) Percent Type Count Natural Beach 941.56 4.09 Marina 2,954.69 0.66 Crib Boathouse 1 Rock 13,250.40 57.58 Mixed Forest 173,600.48 38.88 1 Slip Crib Boathouse 31 Shrub 2,762.59 12.00 Thinned Forest 70,026.82 15.68 2 Slip Crib Boathouse 3 Wetland 667.79 2.90 Overgrowth 17,705.59 3.97 >3 Slip Crib Boathouse 1 Man Made Beach 1.084.87 4.71 Rock 29,510.80 6.61 Pole Boathouse 2 Concrete Ramp 35.39 0.15 Wetland 8,056.49 1.80 1 Slip Fill Boathouse 3 Stone/Gravel Ramp 28.14 0.12 Man Made Beach 1,579.68 0.35 Boathouse on Land 6 Concrete Shore Wall 174.21 0.76 Road 2,652.91 0.59 Crib Dock 109 Metal Shore Wall 25.09 0.11 Landscaped Yard 28,963.10 6.49 1 Slip Crib Dock 25 Stone Shore Wall 2,936.00 12.76 Buffered Lawn 44,762.29 10.02 2 Slip Crib Dock 1 Wooden Shore Wall 566.39 2.46 Unbuffered Lawn 66,713.84 14.94 Cantilever Dock 4 Unbuffered Lawn 541.17 2.35 Fill Dock 2 Floating Dock 52 1 Slip Floating Dock 1 2 Slip Floating Dock 1 Pole Dock 88 1 Slip Pole Dock 2 Marine Railway 9 Bridge 3 Deck 26 Pump House 2 Wooden Ramp 12 Other 9

Total 23,013.60 100.00 Total 446,526.69 100.00 Total 393 Natural 17,622.34 76.57 Natural 211,167.77 47.29

Altered 5,391.26 23.43 Altered 235,358.92 52.71

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2008 Aquatic Invertebrate Data Sheets

The District Municipality of Muskoka

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2008 Terrestrial Plot Monitoring Summary Tables

The District Municipality of Muskoka

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Ril Lake – Township of Lake of Bays Site #1, Plot #1

Total Total Average Basal Relative Relative Relative Tree Species IVI Trees Stems DBH (cm) Area Density Dominance Frequency Acer saccharum (Sugar maple) 14 14 31.57 1.096 87.50 81.29 33.33 202.13 Quercus rubra (Red oak) 1 1 36.30 0.103 6.25 7.68 33.33 47.26 Quercus macrocarpa (Bur oak) 1 1 43.50 0.149 6.25 11.03 33.33 50.61 # Species # Trees # Stems Average DBH (cm) Total BA (m) Summary 3 16 16 32.75 1.35

Basal Area – This is the total basal area for the species. Total basal area is determined by adding up the individual basal areas from each tree. Individual basal areas are based on diameter measurement and are determined from the basal area table.

Relative Density – This is the density of one species related to all species in the plot.

RD = Total # of trees for one species in the plot Total # of all trees for all species in the plot

Relative Dominance (Stand Composition) – This is a percentage of the area that one species occupies in a stand related to all other species.

RDom = Total Basal area of one species (m2) x 100 Total Basal area of all species (m2)

Relative Frequency – This is the relationship between one species distribution in the plot and all other species in the plot. All species will have the same frequency since we are only using one plot.

RF = Frequency of one species in the plot x 100 Total Frequency of all species in the plot

Importance Value – This is an index that profiles the structure of the stand by using the Relative Density, Relative Dominance and Relative Frequency added together. This value is used to compare stands in reference to species composition and stand structure.

IV = Relative Density + Relative Dominance + Relative Frequency

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Appendix 1

Interpretation of water quality data

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Interpretation of Water Quality Data

1. Spring phosphorus

Phosphorus is the nutrient that controls the growth of algae in most Ontario lakes. For this reason, any increase in phosphorus in a lake will tend to increase the quantity of algae that can grow.

High levels of phosphorus can lead to algal blooms that detract from recreational water quality and in some cases affects the habitat of coldwater fish species such as lake trout.

A sensitivity rating is given to each lake in Muskoka based on the lake’s responsiveness to phosphorus inputs and the mobility of phosphorus within the lake’s watershed. A lake can have either a low, moderate or high sensitivity to phosphorus.

Phosphorus samples are collected in the spring during a period called “spring turnover”. This is the best time to sample for phosphorus because the lake is completely mixed and a water sample represents the phosphorus concentration throughout the whole lake.

By sampling spring phosphorus each year it is possible to detect a change in the nutrient status of a lake. Several years of data must be collected to first observe the normal, between-year-differences, before a trend can be identified.

Phosphorus enters a lake naturally through sediment and precipitation. Human inputs of phosphorus enter a lake primarily through surface runoff from sources such as septic system seepage, lawn fertilizer runoff, agricultural runoff and municipal wastewater.

Lakes with phosphorus concentrations below 10 micrograms per litre ( g/L) are considered oligotrophic or unenriched. Those with a phosphorus concentration falling between 11 and 20 g/L are termed mesotrophic or moderately enriched, while lakes with a phosphorus concentration exceeding 20 g/L are called eutrophic and are considered enriched.

Each lake has a threshold concentration, which is equal to the background level of phosphorus plus an additional 50%. If a lake’s measured and modelled (value calculated using a water quality model) phosphorus concentrations over a 10-year period are greater than its threshold value, then the lake is considered “over threshold” and actions will be initiated to reduce the amount of phosphorus entering the lake from its watershed.

A lake that is over threshold can be de-listed after three consecutive phosphorus measurements are below its threshold value.

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2. Secchi depth measurements

Secchi depth is a measurement of water clarity. In Muskoka, the major determinant of water clarity may be either natural colour or an increase in nutrient input from the surrounding watershed.

A lake may naturally be a brown colour due to high levels of dissolved organic carbon (DOC) that comes from the wetlands in a watershed. DOC colours lakes brown and reduces water clarity, but is not an indication of nutrient enrichment. Examples of lakes with naturally high DOC content include Brandy Lake and Tea Lake.

Water clarity can also decrease as nutrients from the surrounding watershed enter and enrich the lake, resulting in high levels of suspended sediments or algal growth.

Water clarity can change weekly or yearly as a result of weather, length of winter ice cover, shoreline development, natural seasonal trends or other impacts. However, when the primary determinant of water clarity is a function of nutrient enrichment, a long-term trend that indicates a reduction in water clarity is an indication of reduced water quality.

In general, where a lake is not coloured by DOC, the higher the secchi depth reading, the clearer the lake and the less nutrients it contains. Lakes with secchi depth measurements over five metres are considered oligotrophic or unenriched. Those with a secchi depth measurement falling between three and five metres are termed mesotrophic or moderately enriched, while lakes with a secchi depth measurement below three metres are called eutrophic and are considered enriched.

3. Temperature and dissolved oxygen measurements

Temperature is a measure of the intensity of heat stored in a volume of water. Temperature patterns affect the solubility of many chemical compounds and influences the effects of pollution on aquatic life.

Dissolved oxygen is a measure of the concentration of oxygen dissolved in water. Adequate concentrations of dissolved oxygen are necessary for the survival of fish and other aquatic organisms. Dissolved oxygen concentration is an indicator of a lake’s ability to support aquatic life.

Dissolved oxygen levels above five milligrams per litre (mg/L) are considered optimal for most aquatic organisms. Most fish cannot survive if levels fall below 3 mg/L. For coldwater species, such as lake trout, a minimum of 6 mg/L is needed, along with a temperature below 10 C. Lakes with dissolved oxygen readings below 0.5 mg/L are considered anoxic.

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Appendix 2

Interpretation of aquatic invertebrate monitoring results

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Benthic Macroinvertebrate Monitoring

Monitoring bottom-dwelling aquatic invertebrate communities has been part of The District Municipality of Muskoka’s Lake System Health Biological Monitoring Program since 2003. In biological monitoring, composition of the aquatic-invertebrate community, the pattern of abundances of different species collected, indicates the health of the ecosystem.

Aquatic invertebrates, such as worms, mollusks, insects, crustaceans, and mites, are common indicators in biological-monitoring programs. These animals are sensitive indicators of the health, or condition of lakes and streams, and different species have different sensitivities to environmental changes such as pollution or habitat alteration. Aquatic invertebrates live between 1 and 3 years and are in constant contact with lake sediments. Contamination and toxicity of sediments affects those animals that are sensitive. For example, lake acidification is accompanied by both a decline in the total number of species present, and an increase in the abundance of those species able to tolerate acidity.

Reference-Condition Approach

One of the challenges of biological monitoring is that the composition of healthy invertebrate communities varies from place to place, and from time to time. We therefore have to understand natural variability to be able to make reliable conclusions about whether or not the community that we find in a given lake is normal or not. One way to determine what normal looks like is to sample reference sites. Reference sites are locations where human impacts (such as pollution, shoreline alteration, and development) are minimal and the aquatic ecosystem is considered to be in the best condition found in Muskoka.

Biological-monitoring assessments can make judgments about the condition of lakes by comparing samples from a given lake of interest (a test lake) against a set of samples from reference lakes. In short, reference lakes define what normal Muskoka invertebrate communities should look like in the absence or near-absence of human influence. Atypical sites, which are biologically different from reference sites, warrant further study to determine why their communities are unusual.

Because we need information from minimally-impacted reference sites before we can evaluate our lakes, much of the focus of our biomonitoring program to-date has been on sampling reference sites. Since reference sites are assumed to be in excellent condition, it doesn’t make sense to report their condition; however, because their communities act as a benchmark for assessing other lakes, it is informative to understand invertebrate-community composition in reference lakes, and to watch for changes in reference lake composition over time. This report serves to characterize reference lake community structure, and gives a preliminary assessment of local test lakes.

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Data analysis

Biological monitoring programs yield large data tables. You can envision such tables as columns of numbers, each column representing the counts of different species collected at a given location. It is very difficult to pick-out ecological patterns in such complex datasets, so it is common practice to simplify data tables into a manageable number of indices that represent meaningful ecological patterns. This is similar to the way stock-market performance is measured using indices like the TSX or the Dow Jones Industrial Average. The District of Muskoka uses several indices to simplify bioassessments, as described in Table 1.

Table 1: Indices used to summarize aquatic invertebrate composition in Muskoka. Indicator What it tells us

The number of taxa is a measure of biological diversity. Richness Number of taxa collected increases with increasing habitat diversity, suitability, and water quality; (Richness) therefore, the healthier a site’s community, the greater its number of taxa.

Percent of collection made-up of Ephemeroptera (mayflies), Odonata (dragonflies and damselflies), and mayflies, dragonflies, damselflies, Trichoptera (caddisflies) are very sensitive to pollution and habitat and caddisflies alteration. They should be prominent in healthy ecosystems, but their (% EOT) numbers will decline in response to stress imposed by human activities.

Percent of collection made-up of Midges (true flies in the family Chironomidae) are tolerant of pollution and midges habitat changes so their dominance indicates water quality problems. (% Chironomidae)

Percent of collected animals that In a healthy ecosystem, the numbers of predators and prey are are predators maintained within a narrow range. Extreme fluctuations in this balance (% predators)* signify that the ecosystem is sick.

Shredders are a group of plant eaters adapted to breaking down leaves, Percent of collected animals that wood, and other plant matter that originates on land but gets transported are adapted to feeding on coarse into waterbodies. Such animals should be abundant if there is a good plant matter connection between a lake and its watershed. In addition to recycling (% shredders)* nutrients, shredders are food for other animals.

Percent of collected animals that Collector-gatherers feed on small pieces of organic matter that arise from are adapted to feeding by the processing activities of shredders (described above). Their presence collecting small pieces of organic indicates a good population of shredders, which provide them with food. matter Like shredders, these animals perform a vital role in energy cycling, and (% collector/gatherers)* are prey for other animals.

The Hilsenhoff index combines information about the abundances of different types of animals collected at a site with information about those Organic pollution score animals’ sensitivities to sewage pollution, farm wastes, and other sources (Hilsenhoff index value) of nutrients like phosphorus, nitrogen, and carbon. High values of this index indicate pollution; low values indicate good water quality.

In healthy ecosystems, the proportion of the aquatic-invertebrate community that is made-up of predators, shredders, collector/gatherers, and other animals is maintained within a narrow range. Marked divergences in abundances of any type of animal signifies a stressed ecosystem.

131 2008 Lake System Health Monitoring Program Data Report

How do your local sites fare?

The Aquatic Invertebrate Data Sheet provides a preliminary evaluation of your lake. If your sites are reference lakes, assumed to reflect the best ecosystem conditions in Muskoka, no assessment is warranted. For test locations, assessments can be made by comparing test-site index values against the averages for Muskoka reference lakes, which are provided in the shaded box at bottom right.

In general,

1. Richness should be high (close to the average for Muskoka or above).

2. % EOT will decrease and % Chironomids will increase over time with water quality impairment.

3. % Predators should be less than the other types of benthos (shredders, collector/gatherers) and these percentages should remain relatively constant over time.

4. The Hilsenhoff Index value should be close to the average for Muskoka or less, as a lower value indicates healthier water.

Even though most of the lakes in Muskoka are quite similar, no two lakes are identical and there are various factors that play a role in determining the relative abundances of different types of aquatic invertebrates. Comparing your lake’s data to the rest of the lakes in Muskoka is not definite, but it can give you an idea. If there is a trend in all the types of indices and data, either above or below normal, it may indicate your lake’s overall quality.

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