Methods Supporting the Development of Food Web Metrics from Benthic Macroinvertebrate Data
This document describes the field, laboratory, and analytical methods employed to generate food web metrics from ongoing benthic macroinvertebrate (BMI) data collected as part of a spring Chinook Salmon habitat monitoring program. BMIs are collected in numerous fish-habitat monitoring programs throughout the Pacific Northwest and elsewhere. These data are typically used to generate indices of biotic integrity for describing water quality or sensitivity of BMI assemblages to environmental stressors such as water temperature and sediment load. However, with recent advances in food web theory and computational methods, the same BMI data can be used to describe the quality of food resources for stream-dwelling fish. Along these lines, we present methods for two independent approaches: (1) metrics based on a topological food web perspective, requiring the compilation of resource-consumer pairings from literature review and laboratory observations; and (2) metrics based on availability of prey items to the drift, which extends an existing model requiring compilation of various life history and ecological traits of individual BMI taxa. Finally, we present preliminary conclusions and a strategy for next steps in the analysis involving validation of the models with empirical observations of invertebrate and fish abundance/diets.
Sullivan S.P. and White S.M. 2017. Methods supporting the development of food web metrics from benthic macroinvertebrate data. CRITFC Technical Report No. 17-05. Prepared for the Bureau of Indian Affairs Rights Implementation Climate Change Contract AO9AV00480 by Rhithron Associates, Inc., Missoula, MT, and Columbia River Inter-Tribal Fish Commission, Portland, OR.