813016.fig.004a
(a)
813016.fig.004b
(b)
Figure 4: Scatter plots of the relationships between the densities of brook trout and brown trout across the study sites. Study sites are divided in three equal-sized groups of acidity classes. In 1994 (a), one outlier with high densities of both species was excluded. In 2004 (b), two outliers with high densities of both species were excluded.