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Valerie Brady and Dan Breneman, Natural Resources Research Institute,

Macroinvertebrate relationships with habitat variables in Green Bay, Lake Michigan, and the St. Louis River Estuary, Lake Superior. Valerie Brady and Dan Breneman, Natural Resources Research Institute, University of Minnesota Duluth. Metadata-bugs.

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Valerie Brady and Dan Breneman, Natural Resources Research Institute,

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  1. Macroinvertebrate relationships with habitat variables in Green Bay, Lake Michigan, and the St. Louis River Estuary, Lake Superior Valerie Brady and Dan Breneman, Natural Resources Research Institute, University of Minnesota Duluth

  2. Metadata-bugs • All relationships are based on Great Lakes Environmental Indicators data collected in 2002-2003 across all 5 Great Lakes. Data being used are from GL coastal wetlands and embayments. • Data are from 62 sites across the US side of the upper Great Lakes, covering all but the most southerly portion of Lake Michigan. • Macroinvertebrate data were collected using dip nets. Samples were collected along at least two transects with one sample on each transect in shallow water (typically 20-50 cm) and one in deeper water (50-100 cm). Large or complex sites had 3 transects. • Dip net mesh size was 500 um. All data were converted to proportions. • Samples were averaged within sites by depth zone (shallow or deep). N = 2 or 3 per zone, depending on site. So there are always 2 points per site. • Macroinvertebrate data were then converted to metrics based on taxa counts, functional feeding groups, behaviours, tolerance to stress, and higher-order taxonomic groups. • Data were ANOVA-tested among sites grouped by dominant vegetation type. Sites significantly different (P<0.05) are marked with different letters.

  3. Metadata - fish • All relationships are based on Great Lakes Environmental Indicators data collected in 2002-2003 across all 5 Great Lakes. Data being used are from GL coastal wetlands and embayments. • Data are from 46 sites across the US side of the upper Great Lakes, covering all but the most southerly portion of Lake Michigan. • Fish were collected using fyke (trap) nets. Small frame nets with small mesh were set in shallow water (0.25 – 0.6 m), and large frame nets with large mesh were set in deeper water (0.5 – 1.2 m). • In most wetlands, nets were set as arrays with two nets set lead-to-lead parallel to shore with wings extending at 45 degree angles. However, some sites were not amenable to this set-up due to steep slopes. In these cases, nets were set singly, perpendicular to shore, with wings extending at 45 degree angles. • Nets fished for 24 to 48 hrs, but were checked daily. Fish abundances were converted to catch-per-unit effort and averaged to the site level. Nets could not be separated based on depth due to the confounding of net depth with net frame and mesh size. • Fish data were then converted to metrics based on taxa counts, feeding groups, and behaviors. • Data were ANOVA-tested among sites grouped by dominant vegetation type. Sites significantly different (P<0.05) are marked with different letters.

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