Table 1.
Overall Kendall’s tau coefficients and Kendall-Theil trends before and after age normalization for legacy contaminants in GL lake trout (excluding walleye samples in Lake Erie) from 2005 to 2014. A number in bold means the results are statistically significant.
| Legacy contaminants | Kendall’s tau coefficient before normalizationa | Kendall-Theil trend before normalization (percentage/year)b | Kendall’s tau coefficient after normalizationa | Kendall-Theil trend after normalization (percentage/year)b |
|---|---|---|---|---|
| PCBs | −0.39 | −7.9 (−6.4, −9.4) | −0.40 | −10.2 (−8.5, −12.1) |
| DDTs | −0.39 | −8.1 (−6.7, −9.6) | −0.48 | −13.2 (−113, −15.1) |
| Dieldrin | −0.36 | −7.6 (−6.1, −9.1) | −0.47 | −11.7 (−9.9, −13.6) |
| Endrin | −0.36 | −9.2 (−7.4, −11) | −0.46 | −10.5 (−8.6, −12.4) |
| Chlordane | −0.41 | −7.7 (−63, −9.1) | −0.48 | −11.4 (−9.8, −13.2) |
| Oxychlordane | −0.31 | −6.6 (−5, −8.2) | −0.53 | −12 (−10.5, −13.5) |
| Nonachlor | 0.01 | 0.1 (1.2, −0.9) | −0.52 | −11.5 (−9.9, −13.2) |
| HCB | −0.22 | −2 (−1.4, −2.7) | −0.21 | −3.7 (−2.4, −4.9) |
a
Kendall’s tau coefficient (from −1 to 1) indicating the slope of the trend.
b
Two numbers in parentheses indicate lower 95% and upper 95% slopes.