Deterioration of the Littoral–Benthic Ecosystem Following Recent Expansion of Signal Crayfish (Pacifastacus leniusculus) in the World’s Clearest Large Lake

• DOI: 10.1007/s10021-023-00846-0
• Publication Date: 2023-05-03T21:06:51Z
• Authors: Facundo Scordo; Scott F. Girdner; Aldo San Pedro; Carina Seitz; Sudeep Chandra
• Keywords: Pacifastacus; Periphyton; Trophic cascade

Abstract Some biological invasions can result in algae blooms the nearshore of clear lakes. We studied if an invasive crayfish ( Pacifastacus leniusculus ) modified biomass and community composition benthic macroinvertebrates therefore led to a trophic cascade resulting increased periphyton biomass, elevated littoral primary productivity, bloom lake with remarkable transparency [Crater Lake, Oregon, USA]. After quantifying changes spatial distribution over 13-year period, we compared littoral–benthic macroinvertebrates, biovolume, composition, nutrient limitation, development locations high low density. In addition, determined alteration structure resulted directional gross production ecosystem respiration. The extent along shoreline Crater Lake doubled leaving less than 20% free from crayfish. At density sites, macroinvertebrate was 99% lower, taxa richness 50% lower at areas. High sites show tenfold greater sixfold higher (chlorophyll ), twofold metabolic presence large filamentous Cladophora sp.). invasion had negative consequences for protected under management USA National Park Service, direct impacts on many levels ecological organization.