Quarterly in situ study results for the Grassland Bypass Project's (GBP) monitoring site between 1996 and 1997.  Statistically significant reduced responses (P<0.05) are indicated with an asterisk.   Statistics were computed between all sites and the Windmill site.  No statistics were computed between sampling dates.  Results are for seven day tests and are indicated by the number of live fish per number of fish counted.  Each value represents the total count for all four cages used at each station.  Initial deployment was eighty fish for each station.  (Key at bottom of table.)


Date Site Location
Windmill B D
(4-day old larvae)
(14-day old larvae)
(4-day old larvae)
(14-day old larvae)
11/961 42/62 63/68 0/2 NA 16/36 NA
2/97 NT 3/13 0/0 NA 0/11 NA
5/97 64/66 0/0 0/24 NA 5/9 NA
8/972 NT 38/38 27/31 NA 0/8 NA

NT=Not tested
NA=Not applicable

1.   Heavy silt accumulation was noted in Site D and F cages.  Light silt accumulation was observed in both the Windmill site and Site B.  Future in situ testing will  determine suspended sediment in station water.

2.   No test deployment was done at the Windmill site due to extreme conditions (stagnant and pH>9.0).  Site B replicate A was retrieved with no cork and replicate C  lost its cork during retrieval.  There were no surviving fish for a growth determination for Site F.  Very light silt accumulation occurred in the Site B cages, moderate silt accumulation in the Site D cages and heavy silt accumulation in the Site F cages.  Some small red worms were found in the site B cages.

[ Return to GPB Toxicity Page ] [ Return to homepage ]