Table 1. Mean (± SD) Body Condition, Age, and Total Mercury Concentrations (THg, raw and standardized) of Yellow Perch Caught in 1996/97 (13) and 2006/07c from 16 Lakes in Kejimkujika,b.
| lake | year | n | condition (g·cm−3) | age (y) | THg (μg·g−1 ww) | 12-cm THg (μg·g−1 ww) |
|---|---|---|---|---|---|---|
| Back | 1996 | 9 | 1.11 ± 0.08a | 5.0 ± 2.1 | 0.13 ± 0.06a | 0.12 |
| 2006 | 10 | 1.04 ± 0.08** | 3.6 ± 1.1 | 0.21 ± 0.04 | 0.19*** | |
| Beaverskin | 1996 | 10 | 1.10 ± 0.05a | 3.7 ± 1.3 | 0.19 ± 0.08abc | 0.20 |
| 2006 | 8 | 1.11 ± 0.06 | 4.2 ± 1.9 | 0.29 ± 0.02 | 0.28** | |
| Big Dam East | 1996 | 8 | 1.17 ± 0.08a | 4.6 ± 1.9 | 0.18 ± 0.08abc | 0.18 |
| 2006 | 8 | 1.06 ± 0.04*** | 3.9 ± 0.9 | 0.20 ± 0.06 | 0.25* | |
| Big Dam West | 1996 | 7 | 1.31 ± 0.07b | 5.4 ± 2.4 | 0.21 ± 0.10 abc | 0.27 |
| 2006 | 8 | 1.25 ± 0.06* | 4.8 ± 2.1 | 0.21 ± 0.06 | 0.24* | |
| Big Red | 1996 | 6 | 1.20 ± 0.13a | 6.8 ± 2.1 | 0.53 ± 0.14abc | 0.41 |
| 2006 | 7 | 1.19 ± 0.07 | 5.8 ± 1.2 | 0.47 ± 0.12 | 0.41 | |
| Cobrielle | 1996 | 6 | 1.16 ± 0.07a | 5.2 ± 1.2 | 0.26 ± 0.07abc | 0.20 |
| 2006 | 6 | 1.10 ± 0.07 | 4.7 ± 0.8 | 0.33 ± 0.07 | 0.25* | |
| Frozen Ocean | 1996 | 9 | 1.30 ± 0.12b | 5.8 ± 2.3 | 0.26 ± 0.16abc | 0.24 |
| 2006 | 9 | 1.20 ± 0.08** | 4.8 ± 2.4 | 0.26 ± 0.11 | 0.22 | |
| Kejimkujik | 1996 | 23 | 1.16 ± 0.09a | 5.2 ± 2.3 | 0.28 ± 0.10bc | 0.30 |
| 2006 | 26 | 1.21 ± 0.14 | 5.3 ± 2.3 | 0.32 ± 0.14 | 0.29 | |
| Loon | 1996 | 9 | 1.20 ± 0.05a | 6.1 ± 2.0 | 0.26 ± 0.11abc | 0.22 |
| 2006 | 9 | 1.16 ± 0.09 | 3.7 ± 1.8* | 0.26 ± 0.11 | 0.30* | |
| Mountain | 1996 | 8 | 1.17 ± 0.07a | 5.1 ± 2.5 | 0.22 ± 0.12abc | 0.19 |
| 2006 | 9 | 1.09 ± 0.07* | 2.7 ± 1.7* | 0.21 ± 0.11 | 0.21* (0.20)d | |
| North | 1996 | 9 | 1.09 ± 0.06a | 5.4 ± 2.2 | 0.37 ± 0.14c | 0.30 |
| Cranberry | 2006 | 9 | 1.10 ± 0.10 | 5.6 ± 2.5 | 0.49 ± 0.24 | 0.36* |
| Pebbleloggitch | 1996 | 9 | 1.16 ± 0.09a | 5.2 ± 2.2 | 0.16 ± 0.04ab | 0.19 |
| 2006 | 9 | 1.14 ± 0.04 | 4.3 ± 1.2 | 0.20 ± 0.05 | 0.22* (0.19)d | |
| Peskawa | 1996 | 20 | 1.18 ± 0.08a | 4.4 ± 2.0 | 0.24 ± 0.13abc | 0.28 |
| 2006 | 27 | 1.20 ± 0.13 | 5.2 ± 2.6 | 0.25 ± 0.11 | 0.24* | |
| Peskowesk | 1996 | 8 | 1.13 ± 0.06a | 5.1 ± 2.1 | 0.28 ± 0.16abc | 0.21 |
| 2006 | 10 | 1.16 ± 0.08 | 5.0 ± 2.4 | 0.36 ± 0.17 | 0.27* | |
| Puzzle | 1996 | 8 | 1.08 ± 0.06a | 4.9 ± 2.4 | 0.23 ± 0.10abc | 0.25 |
| 2006 | 9 | 1.08 ± 0.10 | 5.5 ± 2.6 | 0.33 ± 0.12 | 0.29** | |
| Upper Silver | 1996 | 7 | 1.08 ± 0.08a | 3.7 ± 1.5 | 0.14 ± 0.06a | 0.19 |
| 2006 | 10 | 1.08 ± 0.06 | 2.5 ± 1.7 | 0.13 ± 0.04 | 0.12* |
a
Asterisks represent statistical within-lake differences (* p < 0.05, ** p < 0.01, *** p < 0.001, t-tests, ANCOVA, or polynomial regression) between years.
b
Letters represent statistical differences (ANOVA) among lakes within each period.
c
2006/07 data mathematically pooled except in Kejimkujik and Peskawa lakes; see Methods for details.
d
Values in brackets had outliers removed.