Forest restoration thinning and burning treatments create habitat mosaics and facilitate succession of grasshopper and cricket communities (Orthoptera)

Forest restoration in fire-prone coniferous forests in the western United States using fuel management projects with thinning and prescribed broadcast-slash burning has proven effective in reducing the risk of high-severity stand-replacement wildfires. These treatments have additional potential benefits in creating a wider spectrum of habitat types, in different successional stages, for both vertebrate and invertebrate wildlife across the landscape. In this 6-year case study, we examined the successional responses of vegetation/habitat variables and the grasshopper/cricket community (Orthoptera) before, during, and after a forest thinning treatment, followed by a prescribed broadcast-slash burn in a mixed-conifer forest in northern New Mexico, USA. We found that the treatments resulted in rapid colonization by 18 species of grasshoppers (Acrididae) and the Mormon cricket (Tettigoniidae); the dominant forest orthopterans, two species of camel crickets (Rhaphidophoridae), continued to thrive in the treated sites. Colonizing grasshoppers in the first post-thinning year were dispersing adults, but nymphs appeared in year 2, indicating successful on-site reproduction. Species with good dispersal traits (strong flyers) colonized first, followed by ambulatory (brachypterous) species. Vegetation successional processes were dominated by post-disturbance legacy perennial plants (with live soil root stocks, bulbs and corms), whereas Orthoptera succession followed a pattern of “relay succession,” with some species peaking early and then declining while other species increased through time. Species-specific patterns were associated with various vegetation and forest floor habitat variables. Forest restoration projects create a landscape mosaic of different habitat types and promote greater diversity of grasshoppers and crickets compared to closed-canopy forests.