Mean reproduction per surviving female for Daphnia magna in water samples collected from the Grassland bypass Project's (GBP) monitoring site between 1996 and 2001.  Statistically significant reduced responses (P<0.05) are indicated with an asterisk.  Statistics were computed between all site means and the DMC ambient water sample.  No statistics were computed between sampling dates.  Results are for seven day tests.  (Key at bottom of table.)

Date Site Location
B C D F DMC Laboratory Control
10/96 16.8 20.2 17.9 13.1 12.9 16.0
11/96 30.6 21.8 21.9 22.4 21.5 15.9
12/96 23.2 14.0 17.2 17.8 16.8 14.8
1/97 15.2 15.4 15.3 15.6 13.6 10.9
2/97 25.1 23.0 22.8 20.1 18.0 22.7
3/97 22.8 16.6 15.3 9.7 8.9 5.5
4/97 23.6 24.4 24.6 16.3 12.9 10.0
5/97 30.6 33.8 34.0 21.6 17.2 20.0
6/97 50.9 58.8 41.1 50.2 29.6 31.6
7/97 35.6 28.1 33.2 27.7 19.1 17.1
8/97 55.8 55.4 53.1 54.1 40.7 44.3
9/97 33.0* 31.2* 45.8 47.1 39.7 23.2
10/97 42.2 37.9 41.7 34.8 34.9 32.0
11/97 37.3 28.6 34.0 30.0 22.0 21.51
12/97 46.0 44.5 41.2 32.7* 43.6 21.1
1/98 13.7* 21.8 18.5* 14.5* 27.4 0
2/981 67.0 70.5 69.9 61.3 39.32 0
3/98 32.0 28.9 28.0 29.1 28.5 0
4/98 18.7 25.2 19.6 20.2 10.2 0
5/98 34.90 34.60 31.60 21.10 20.10 18.40
6/98 30.8 5.70 7.88 2.30 9.003 0
7/98 10.80 11.90 12.60 8.20 6.603 5.90
8/98 57.50 71.30 49.10 29.90 32.70 28.20
9/98 46.40 56.20 50.70 45.80 40.50 50.20
10/98 14.70* 22.90 12.50* 22.00 24.20 23.50
11/98 53.40 50.00 53.40 50.55 38.90 24.30
12/98 30.20 38.40 35.00 35.80 30.00 26.80
1/99 33.00 28.70 31.20 22.90 14.90 48.00
2/99 25.40 24.00 31.70 21.10 23.80 20.30
3/99 65.40 69.60 70.90 57.40 45.10 52.70
4/99 17.10 24.40 20.60 21.60 19.90 13.80
5/99 31.60 36.00 33.80 37.44 30.80 39.20
6/99 23.80 24.00 21.20 18.50 8.603 10.33
7/99 31.10 35.90 32.60 27.20 12.80 15.70
8/99 19.89 23.20 24.30 19.90 11.40 12.30
9/99 29.20 37.70 36.10 28.40 17.90 14.60
10/99 31.70 25.70 28.40 22.20 22.80 16.80
11/99 16.20 11.70 10.10 14.80 5.303 7.303
12/99 34.90 32.00 43.00 37.70 31.20 40.90
1/00 18.90 22.30 23.00 24.90 15.00 14.00
2/00 37.10 29.00 24.50 22.70 22.50 32.10
3/00 10.56 10.64 13.03 10.55 6.24 12.72
4/00 14.50 17.30 11.20 10.50 9.703 11.60
5/00 13.40 18.50 12.50 9.70 11.40 17.70
6/00 21.50 29.10 35.00 22.10 15.50 16.60
7/00 27.30 36.80 31.40 17.00 8.80 28.60
8/00 20.90 18.20 21.50 26.80 16.30 14.50
9/00 42.4 38.9 39.9 41.6 48.7 31.8
10/00 29.8 41.5 23.9 25.7 31.8 17.7
11/00 45.7 40.4 43.9 35.1 22.8 26.3
12/00 13.7 15.7 13.3 11.2 13.4 4.4*
1/01 30.8 31.3 46.2 36.9 30.8 27.1
2/01 31.2 25.7 25.1 29.9 27.2 27.5
3/01 11.7 21.9 19.3 15.6 13.4 17.8
4/01 30.7 28.6 36.5 26.2 24.9 24.8
5/01 0** 25.0 27.5 23.3 13.1 25.2
6/01 18.9* 28.3 27.6 47.9 44.5 36.4
7/01 25.3 28.5 16.8 17.7 26.2 15.9
8/01 11.7* 42.9 15.5* 52.5 27.1 36.3
9/01 27.7 31.5 32.5 31.5 25.6 20.7

Key
NT=No sample collected
DMC=Delta Mendota Canal
"*" = Statistically significant

Footnotes
1.  Increased reproduction for the February, 1998, sampling period is due to increased nutrients added to the test water.
2.  DMC/Control water failed to meet the survival (>80%) and acceptability criteria.
3.  DMC/Control water failed to meet the reproduction (> 10 neonates/adult) acceptability criteria.

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