presented by Dan Selbie, Ph.D

1. DFO’s Lakes Research Program
• Historical Limnological & Fisheries Research
and Monitoring
§ 1987-1993 – Shuswap and Mara Lakes
(Nidle & Shortreed 1996, Morton and Shortreed 1996)
§ 2007-2008 – Mabel Lake
§ 2008 – Little Shuswap Lake
§ 2011 – Shuswap and Mara Lakes

2. Shuswap Lakes DFO Deep Stations 2011
L. Shuswap Lake
Seymour Arm
Main Arm
Shuswap Lake
Anstey Arm
Salmon Arm
Mara Lake

3. Shuswap Lake
Whole Lake Seasonal Mean Photosynthetic Rate
300
Whole Lake
250
Photosynthetic Rate (mg C/m /d)
2
200
150
100
50
0
1988 1989 1991 2011
Fisheries and Oceans Canada, Science Branch, D.T. Selbie unpublished data

4. Shuswap Lake
Arm-Specific Seasonal Mean Photosynthetic Rates
300 300
Main Arm Seymour Arm
250 10,583 salmon/km2 250 4,494 salmon/km
2
Photosynthetic Rate (mg C/m /d)
Photosynthetic Rate (mg C/m /d)
2
2
200 200
150 150
100 100
50 50
0 0
300 300
Anstey Arm Salmon 10,649 salmon/km2
250 2,437 salmon/km
2 250
Arm
Photosynthetic Rate (mg C/m /d)
Photosynthetic Rate (mg C/m /d)
2
2
200 200
150 150
100 100
50 50
0 0
1988 1989 1991 2011 1988 1989 1991 2011
Fisheries and Oceans Canada, Science Branch, D.T. Selbie unpublished data

5. Mara Lake
Whole Lake Seasonal Mean Photosynthetic Rates
300
Mara Lake
1,689 salmon/km2
250
Photosynthetic Rate (mg C/m /d)
2
200
150
100
50
0
1987 2011
Fisheries and Oceans Canada, Science Branch, D.T. Selbie unpublished data

6. 300
Salmon Arm
250
Shuswap Lake 200
Arm-Specific Seasonal Mean Size- 150
Fractionated Photosynthetic Rates 100
50
Seasonal Mean Photosynthetic Rate (mgC/m2/yr)
0
300
Seymour Arm
250
200
150
100
50
0
300
Main Arm
250
200
150
Microplankton PR (>20µm)
100
Nanoplankton PR (>2 µm <20µm)
Picoplankton PR (>2 µm <20µm) 50
0
1987 1988 1989 1991 2011
Fisheries and Oceans Canada, Science Branch, D.T. Selbie unpublished data Year

7. Fraser Basin Sockeye Nursery Lakes
Comparison of Seasonal Mean Photosynthetic Rates
450
400
Seasonal Mean Photosynthetic Rate
350
300
(mgC/m2/d)
250
200
150
100
50
0
Chilko
Takla
Trembleur
Mabel
Quesnel
Harrison
Fraser
Cultus
Kamloops
Francois
Seton
Lillooet
Stuart
Chilliwack
Anderson
Shuswap
Bowron
Lake
Fisheries and Oceans Canada, Science Branch, Modified from J.H. Hume et al in prep