Conservation of Grassland Leafhoppers: A Brief Review

Abstract

The leafhoppers, planthoppers and their allies (collectively known as the Auchenorrhyncha) are presented as a group of insects that are highly appropriate for studying grassland ecology and conservation, evaluating the conservation status of sites and monitoring environmental and habitat change. Semi-natural grasslands typically support dense populations and a wide range of species with diverse ecological strategies. Their numerical dominance in many grasslands means that they have considerable functional significance, both as herbivores and as prey for higher trophic levels. Population and assemblage studies are supported by good ecological knowledge about most species and modern identification keys. Hitherto, most studies have focused on the composition and structure of assemblages and how they are affected by conservation management. However, grasslands support many rare species with small and fragmented populations which deserve conservation attention in their own right, and recent work has started to reflect this. The effects of management on the composition and structure of grassland leafhopper populations and assemblages are described and an assessment is given of the main threats facing individual species and overall diversity. There is a need to synthesise the scattered literature on grassland leafhoppers, to provide a model for how the composition and structure of populations and assemblages respond to major environmental and anthropogenic gradients across large biogeographic areas. Such an analysis could help predict the impact of likely future changes in land use and climate.

Biological consequences of invasion by reed canary grass (Phalaris arundinacea)

“…We analyzed Homopterans separately as a biological integrity indicator assemblage because they have previously been demonstrated to be sensitive indicators of the overall arthropod community in similar habitats (Biedermann et al 2005;DeLong 1948;Hamilton 2005). Finally, because voles and mice are known to use different habitats and rely on different food sources, and because we anticipated that their responses to dominance by RCG might differ, we conducted separate correlations between vole abundance (Microtus ochrogaster and M. pennsylvanicus) and white-footed mice abundance (Peromyscus leucopus), as well as total mammal abundance.…”

“…Most alien plants across North America were selected and introduced for their relative unpalatability to insects (Tallamy 2004) and, often having escaped their specialist consumers upon introduction, they tend not to accrue appreciable native specialist insects via hostuse switching (Kean and Crawley 2002;Zuefle et al 2008). Ironically, RCG is an important host plant for native insects across its native range in Europe (especially Homopterans), where Biedermann et al (2005) have reported it facing competitive pressure from invasive North American plants.…”

Phylogeny of the leafhopper subfamily Deltocephalinae (Insecta: Auchenorrhyncha: Cicadellidae) and related subfamilies based on morphology

“…Other genera are less constrained to particular plant taxa, and feed on a variety of herbaceous and woody flowering plants. Because of their high abundance, degree of host-plant specialisation, and responsiveness to disturbance, conservationists have recognised grassland leafhoppers as excellent indicators of habitat quality and ideal organisms for use in studying grassland biodiversity and conservation (Hamilton, 1999;Biedermann et al, 2005). In grasslands, deltocephalines are among the most numerically dominant and speciose groups of herbivores (Hamilton, 1995;Whitcomb et al, 1987a, b;Dietrich, 1999).…”

Potential Effects of the Loss of Native Grasses on Grassland Invertebrate Diversity in Southeastern Australia

“…Grasshoppers in pampas grassland were not adversely affected by such intrusions [10], and no consistent relationship was found between ant species richness and degree of replacement of native grasses [8]. However, leafhoppers in German grasslands were adversely affected [11]. Invasion of prairie grasslands in the USA Midwest by exotic grasses is claimed to be detrimental to the survival of populations of the Dakota skipper (Hesperia dacotae L.) [12].…”