Table 1: Osoyoos Lake 2005-13 crustacean zooplankton biomass (µg L-1 dry weight) and production rates (µg L-1 d-1 dry weight shown in parentheses) based on biomass averages from samples collected every 2-3 weeks during May-October of each year. Egg-ratio production estimates were calculated for Diacyclops thomasi, Leptodiaptomus ashlandi, Bosmina longirostris, Daphnia thorata and Diaphanosoma leuchtenbergianum and are shown in parentheses on the first rows beside the biomass estimates. Egg-ratio production was not calculated for Epischura nevadensis (eggs broadcast) and Leptodora kindtii (low biomasses). Parenthetical estimates below the biomass estimates show production rates calculated using the size frequency and increment summation methods, in that order. Production was not calculated for chironomids, which were collected separately by means of the larger net used to sample Mysis.
| Year |
Nauplii and rotifers |
Diacyclops |
Leptodiaptomus |
Epischura |
Bosmina |
Daphnia |
Diaphanosoma |
Leptodora |
Total |
Chironomid |
| 2005 |
3.1 |
16.9 (0.86) |
56.2 (2.46) |
5.3 |
1.6 (0.04) |
11.0 (0.59) |
6.0 (0.81) |
0.9 |
101 |
nd |
| 2006 |
3.8 |
34.4 (1.04) |
53.2 (2.11) |
5.2 |
0.5 (0.03) |
6.7 (0.35) |
4.0 (0.27) |
0.47 |
108 |
nd |
| - |
- |
(1.98, 0.67) |
(3.16, 0.29) |
(0, 0.01) |
- |
- |
- |
- |
- |
- |
| 2007 |
4.2 |
44.5 (0.75) |
52.3 (2.60) |
8.1 |
2.1 (0.17) |
20.3 (1.47) |
7.0 (0.81) |
4.66 |
143 |
nd |
| - |
- |
(1.77, 0.53) |
(3.91, 1.02) |
(0.1, 0.04) |
- |
- |
- |
- |
- |
- |
| 2008 |
6.8 |
54.0 (1.36) |
48.3 (2.38) |
3.3 |
1.1 (0.07) |
13.9 (1.08) |
6.0 (1.24) |
2.09 |
135 |
nd |
| - |
- |
(2.27, 0.89) |
(4.77, 0.94) |
(0.04, 0.01) |
- |
- |
- |
- |
- |
- |
| 2009 |
13.5 |
62.5 (1.40) |
54.1 (1.86) |
4.3 |
2.0 (0.20) |
21.03 (1.50) |
4.5 (0.94) |
1.62 |
164 |
0.2 |
| - |
- |
(9.77, 6.59) |
(10.74, 4.29) |
(0.07, 0.01) |
- |
- |
- |
- |
- |
- |
| 2010 |
4.6 |
68.7 (1.66) |
5.7 (1.08) |
1.9 |
2.4 (0.26) |
12.5 (1.45) |
2.3 (1.14) |
1.96 |
100 |
0.2 |
| - |
- |
(2.9, 1.41) |
(0.5, 0.09) |
(0.03, 0.02) |
- |
- |
- |
- |
- |
- |
| 2011 |
5.7 |
23.7 (1.60) |
30.5 (3.16) |
1.6 |
0.7 (0.08) |
3.7 (0.39) |
2.3 (0.98) |
0.98 |
69 |
0.4 |
| - |
- |
(2.27, 1.35) |
(3.07, 1.71) |
(0.04, 0.01) |
- |
- |
- |
- |
- |
- |
| 2012 |
5.4 |
25.3 (1.06) |
32.5 (2.54) |
2.6 |
1.6 (0.12) |
4.5 (0.97) |
3.3 (0.89) |
0.91 |
76 |
0.2 |
| - |
- |
(1.69, 0.62) |
(3.42, 0.27) |
(0.05, 0.04) |
- |
- |
- |
- |
- |
- |
| 2013 |
4.5 |
19.2 (1.09) |
19.5 (1.76) |
4.6 |
1.0 (0.18) |
3.7 (0.46) |
4.1 (1.20) |
0.14 |
57 |
0.2 |
| - |
- |
(1.36, 0.55) |
(2.72, 0.26) |
(0.09, 0.03) |
- |
- |
- |
- |
- |
- |