Mobility and microhabitat utilization in a flightless wetland grasshopper, Chorthippus montanus (Charpentier, 1825)

Abstract

Wetlands are among the most threatened habitat types on our planet. Their decline will probably even intensify under climate change. Many biota are strongly dependent on wetlands, including a large number of invertebrate species. The populations of such hygrophilous species become increasingly disconnected due to the ongoing fragmentation of their habitats. This is particularly true for species with reduced dispersal capacities, such as flightless insects. We studied mobility, population size and microhabitat utilization in a population of an endangered grasshopper species, the Water-meadow Grasshopper, Chorthippus montanus. Our mark-recapture study revealed that the cumulative movement distance of the adults was on average 23.5 m with a maximum of 104 m. The microhabitat analysis showed that both sexes of C. montanus preferred warmer patches with greater radiation than measured at control sites. Niche overlap among sexes was stronger than expected by chance, while niche overlap between insects and controls showed the opposite pattern. Our results suggest that C. montanus is strongly restricted to its habitat and is probably not able to cross larger distances through unsuitable vegetation. Hence, we assume that the populations of this flightless insect species are strongly isolated. However, the effect of the rare macropterous morph of C. montanus on gene flow remains unknown. Wetland restoration is crucial to reconnect the existing wetland patches in Central Europe and thereby reduce the negative effects of habitat fragmentation on wetland species.

Spatial heterogeneity in landscape structure influences dispersal and genetic structure: empirical evidence from a grasshopper in an agricultural landscape

“…) and limited movement distances of adults (Weyer et al . ). In phytophagous insects, a general relationship between mobility and gene flow has been documented with gene flow usually extensive and weakly declining with distance in highly mobile species while it was declining rapidly with distance to produce IBD in less mobile species (Peterson & Denno ).…”

The Interactive Effects of Pulsed Grazing Disturbance and Patch Size Vary among Wetland Arthropod Guilds

“…The similar assemblages in both restored habitat types suggests that mounds and terraces were equally isolated from the reference area, which was presumably the source of new arthropod recruits to the entire restored area. Early colonizers of restored habitats tend to be more mobile taxa [46], [61], and even flightless insects can often travel several meters [62]. Therefore, the arthropods we encountered in our study plots after our disturbance treatments may have all had relatively high mobility at the spatial scale of our study plots, which could have muted interactions between disturbance and patch size treatments.…”

Climatic effects on population declines of a rare wetland species and the role of spatial and temporal isolation as barriers to hybridization

“…). Ongoing habitat deterioration caused by land use change represents the main threats for C. montanus populations in the study region (Weyer, Weinberger & Hochkirch ). The species is classified as Near Threatened in Germany (Maas, Detzel & Staudt ) and Vulnerable in Switzerland, the Netherlands and Luxembourg (Proess & Meyer ; Monnerat et al .…”

“…). The species is flightless and its mobility is low (Weyer, Weinberger & Hochkirch ). Nymphs hatch in May and adults are found from July to November.…”