The following details techniques for sampling benthic macroinvertebrates with a variety of off-shore and on-shore techniques.  Dipnet shoreline sweeps are recommended for in concert with each method.  Shoreline sampling protocols include rock picking (visual survey), kick net, and minnow trapping (termed "activity" trap).  Offshore sampling includes grabs and plankton net tows.  These protocols are recommended for 20-40 ha lakes.  Number of samples needed for each methodology will vary by location and method – investigators should perform a pilot study to determine these variables.

Shoreline sweeps:

The authors recommend sweeping the shoreline vegetation with dipnets to collect adult insects each time a site is visited.  If necessary, collections can be standardized by sweeping over a fixed-time period or fixed area.

Offshore sampling:

At nighttime, vertical net tows will capture invertebrates that are benthic by day but planktonic at night (e.g., Mysis, Chaoborus).  The net has an aperture of 0.5 m² and is fitted with a 500-800-mm mesh net.  The net is lowered to the bottom, raised 1 m to prevent filling with sediment, held stationary for 1 min to allow redistribution of organisms in the overlaying water column, and then pulled to the surface at a rate of 0.25 – 0.5 m per sec.  Net contents are emptied into a bottle through a 1-cm or larger ball valve or petcock in the cod end and the net is rinsed three times by backwashing to ensure sample removal.