The relationship between the decline of macroinvertebrate standing crop and the loss of aquatic habitat due to box-cut access channel construction was assessed on Lake Tohopekaliga. Channelization of natural lake bottom had an adverse effect on benthic productivity by increasing both taxon richness and numbers of organisms routinely utilized by sportfish. For this study, channel substrate supported only 54% of the total standing crop of fish food organisms found in littoral substrate. Macroinvertebrates associated with vegetation were eliminated by the destruction of rooted macrophytes; approximately 420 fish food organisms were lost for every cubic meter of vegetated water column altered by channelization. It was estimated that an average standing crop of 840,000 fish food organisms would be lost due to the construction of a "standard" 200 X 10 X 2 m box-cut access channel.
