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Macroinvertebrate Update Title Page
Figures

Figure 2.

Estimated density of mayflies (number per square meter; ±1 standard error) by study area, weighted by area of strata. The wash frame sieve size was changed from a U.S. Standard Sieve no. 30 (0.595 µm), used in 1992, to a U.S. Standard Sieve no. 16 (1.18 mm) in 1993. Horizontal line indicates grand mean.

**Sampling not conducted in 2003 because of budget constraints.

*Sampling not completed because of high water.

**Sampling not conducted in 2003 because of budget constraints.

*Sampling not completed because of high water.

**Sampling discontinued in 2001.

**Sampling not conducted in 2003 because of budget constraints.

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Page Last Modified: April 17, 2018