FINAL REPORT - International Joint Commission

ANNEX 3
Table C-11: Environmental results for candidate plans by interest and region based on the
extreme stochastic supply sequence S1—the century with the most severe
Lake Ontario supply drought
S1 – Extremely Dry (Environmental – Ratios)
Environmental Performance Indicators Plan A + Plan B + Plan D + Plan E
Lake Ontario
Wetland Meadow Marsh Community 0.88 1.22 1.01 1.44
Low Veg 18C - spawning habitat supply 0.95 1.01 0.99 0.98
High Veg 24C - spawning habitat supply 1.15 1.02 1.12 1.01
Low Veg 24C - spawning habitat supply 0.97 1.00 0.98 1.04
Northern Pike - YOY recruitment 1.04 1.02 1.06 1.00
Largemouth Bass - YOY recruitment 1.02 0.99 1.07 0.98
Least Bittern (IXEX) - reproductive index 0.80 1.05 0.84 1.12
Virginia Rail (RALI) - reproductive index 0.77 1.07 0.83 1.11
Black Tern (CHNI) - reproductive index 0.77 1.07 0.84 1.11
Yellow Rail (CONO) - preferred breeding habitat 0.85 0.99 0.87 1.06
King Rail (RAEL) - preferred breeding habitat 0.75 0.96 0.76 1.17
Upper River
Low Veg 18C - spawning habitat supply 0.97 1.00 0.97 1.04
High Veg 24C - spawning habitat supply 1.01 1.01 1.01 1.01
Low Veg 24C - sspawning habitat supply 0.96 1.00 0.97 1.02
Northern Pike - YOY recruitment 1.00 1.01 1.00 1.04
Largemouth Bass - YOY recruitment 0.98 1.00 1.00 1.01
Northern Pike - YOY net productivity 8.62 2.33 1.49 6.39
Virginia Rail (RALI) - reproductive index 1.19 1.17 1.25 0.99
Muskrat (ONZI) - house density in drowned
river mouth wetlands 0.51 4.13 0.43 15.81
Lower River
Golden Shiner - suitable feeding habitat area 1.03 1.08 0.95 1.09
Wetlands fish - abundance index 1.00 1.10 0.95 1.08
Migratory wildfowl - habitat area 1.13 1.13 0.95 1.13
Least Bittern - reproductive index 1.15 1.10 0.99 1.14
Virginia Rail (RALI) - reproductive index 0.96 0.96 1.16 0.96
Migratory wildfowl - productivity 1.07 1.05 0.97 1.08
Black Tern (CHNI) - reproductive index 1.03 1.04 1.15 1.05
Northern Pike (ESLU) - reproductive area 1.01 1.00 0.92 1.05
Frog sp. - reproductive habitat surface area 0.75 0.79 1.08 0.81
Eastern Sand Darter (AMPE) - reproductive area 1.01 1.01 1.03 1.01
Spiny Softshell Turtle (APSP) -
reproductive habitat surface area 1.04 1.03 1.07 1.01
Bridle Shiner (NOBI) - reproductive habitat
surface area 1.00 1.00 0.96 0.97
Muskrat (ONZI) - surviving houses 0.96 0.94 1.07 0.97
Percentage “good” scores for each plan 16% 19% 22% 28%
Overall Environmental Index 0.99 1.31 0.97 2.33
Notes to Table C-11:
1. Figures represent the impact relative to Plan 1958-DD expressed as ratios, where 1 represents no change from
58-DD, > 1.00 an improvement relative to 58-DD, and < 1.00 a deterioration relative to 58-DD.
2. S1 through S4 represent four separate 101-year extreme centuries selected from the 50,000-year stochastic series,
where S1 is extremely dry, S2 is extremely wet and has a large range, S3 is similar to historical and S4 has the
longest drought.
3. Aqua shading identifies species at risk.
4. Yellow shading indicates essentially no change from 1958-DD (within 10% difference). Anything above 1.10 is
marked in blue and anything below 0.90 is marked in red.
224
Options for Managing Lake Ontario and St. Lawrence River Water Levels and Flows