|
February 19 through March 5, 2006, Report No.
3
Oakdale:
A total of
9,637 juvenile Chinook salmon were captured between February
20 and March 5, increasing the season total to 42,058
(Figure 1). Daily catch ranged from 48 to 1,543 Chinook.
Average forklength was 35.3 mm and ranged from 29 mm to 156
mm. Average weight for captured Chinook was 0.4 g and
ranged from 0.1 g to 41.6 g.
Two yearling
Chinook (137 mm and 156 mm; 30.3 g and 41.6 g, respectively)
were also captured on February 25, but were not included in
the total catch or in calculations for mean length or
weight.
No O. mykiss were captured during the sampling period
Figure 1. Chinook
Catch at Oakdale versus flow at Orange Blossom Bridge.
One trap efficiency test was conducted at Oakdale on
February 23 with a resulting efficiency of
24.8% (Table 1). Previous efficiencies for this season
ranged from 1.9 % to 7.5% and it appears that the higher
efficiency for this test was associated with lower flows
during the release-recapture period. Average daily
flows at OBB on February 23-24 were 498 cfs and 481 cfs,
respectively, compared with flows for previous tests
that were between 1,572 and 1,747 cfs.
Table 1. Release
and recapture data for trap efficiencies conducted at
Oakdale.
|
Date |
# Released |
# Recaptured |
Trap Efficiency |
Mean Length @ Release (mm) |
Mean Length @ Recapture (mm) |
Turbidity (NTU) |
Flow @ OBB |
|
2/23/06 |
864 |
214 |
24.8% |
35.0 |
35.9 |
2.95 |
498 |
Caswell:
Caswell (RM 8.6) screw traps were not operated during this
sampling period but are scheduled for installation on March
7.
Environmental Data:
Instantaneous water temperature taken at the Oakdale screw
trap ranged between 46°F and 50.4°F. Turbidity at Oakdale
ranged from 1.0 NTU to 9.6 NTU. During the sampling period,
releases from Goodwin Dam ranged between 354 cfs and 3,534
cfs. Flows at Orange Blossom Bridge (OBB; RM 46.9) ranged
from 481 cfs and 3,318 cfs and at Ripon (RIP; RM 15.8) from
691 cfs and 3,217 cfs. |
