Recent trends in life-history research on benthic macroinvertebrates

Life-history research has a long tradition in benthic biology because of its value in explaining patterns observed in nature, quantifying trophic relationships and energetics, and interpreting experimental results. We examined articles published in the Journal of the North American Benthological Society (J-NABS) during a 23-y period (volumes 5-27) to determine trends in life-history research and to assess future needs in these types of studies. Of the 9 life-history elements we examined, growth and mortality of benthic macroinvertebrates were most commonly reported in the 412 J-NABS Studies containing >= 1 of these elements Recruitment and dormancy were the least-studied elements, and development, reproduction, dispersal, voltinism, and phenology were intermediate. Most Of these Studies were based on aquatic insects, especially Ephemeroptera and Trichoptera, and mollusks (particularly bivalves). Detailed life histories of single species published in J-NABS have averaged similar to 1/volume, With most Studies being on Ephemeroptera, Plecoptera, Trichoptera, and Odonata. Both detailed life-history Studies and Studies containing life-history elements have declined over time, especially when considered as a percentage of articles published in J-NABS In a timeline of important developments in life-history studies, 4 time periods or themes were evident 1) an emphasis on descriptive natural history, which was the earliest type of ecological research conducted and which extended into the 1970s, 2) synthesis of life-history information in books and review articles, which was most prevalent in the 1970s and 1980s, 3) adoption Of functional-feeding groups as a measure Of trophic Status of benthic organisms, which began in the 1970s and continues through today, and 4) the use of a species-trait approach to examine both basic and applied aspects of benthic biology, which began in the 1990s, is an expanding research area, and is a valuable application of life-history information. Life-history research has been published more often in specialized proceedings and regional journals than in J-NABS Clearly more life-history research is needed, but time, logistical considerations, and funding constraints restrict professional benthologists from conducting this kind of research Perhaps anglers and those participating in volunteer monitoring groups can be encouraged to conduct Studies to provide this needed information