Orthoptera Assemblages Research Articles

Conservation Prioritization of Orthoptera Assemblages on a Mediterranean Island

In response to the ongoing global extinction, conservationists must prioritize future conservation investments to ensure that such measures are biologically effective and economically viable. To propose an effective conservation plan for Orthoptera assemblages on Cyprus Island, we introduce the Standardized Conservation Index (StCI), a biodiversity index accounting for the conservation value (ci), presence, dispersal ability, endemism and conservation status of a species. We evaluated the effect of eleven environmental variables on StCI, ci, species richness and the Shannon–Wiener diversity index, using linear and generalized linear models. Species and environmental data were collected in 60 localities that were placed along four elevational zones and included seven habitat types. Our results revealed the importance of rural mosaics and forests for the conservation of Orthoptera. The Shannon–Wiener diversity index failed to show the importance of high-altitude forests. The Orthoptera species diversity was favored by flower heads and the soil humidity, while rock cover and high shrubs had a positive and negative effect, respectively, on the StCI and ci values. Our results underline the value of StCI in complementing traditional diversity indices, as a scale-independent index that can be used for different taxa to prioritize sites of conservation concern.

How can an intensively used agricultural landscape preserve diversity of Orthoptera assemblages?

Protecting biodiversity of agricultural lowlands is one of the main topics of European nature conservation. Understanding the relationship and interaction between cultivated and other habitat types is necessary since arable lands cover a significant part of the landscape, but former studies rather focus on the remaining semi-natural sites. Orthoptera assemblages, which are sensitive indicators of habitat structure and conservation value, were studied in a traditional intensively used agricultural area (it has been cultivated for several decades or even 250 years) to assess how arable land and ruderal linear habitats together can preserve insect diversity. Twenty-nine Orthoptera species, including protected Gampsocleis glabra, Acrida ungarica and Celes variabilis were recorded. We identified four assemblages and their character species reflecting intensity of land use. Assemblages of agricultural sites differed from the assemblages of semi-natural habitats used as control group. Revealing their quantitative composition, ratios of lifeforms and ecotypes, character species, and use of Grasshopper Conservation Indexes (GCI) helped to identify habitat types that can effectively preserve natural insect diversity, even under long-term intensive land use regime.Implications for conservationConsidering our findings, the role of linear ruderal habitats and less intensively cultivated arable lands covered by alfalfa and red clover in maintaining of biodiversity is higher than it was formerly assumed. Increasing ratio of these less intensive cultures (at least to 5%, optimally 8–10%) and its connection with each other and linear ruderal habitats may provide temporary habitats and corridors for metapopulations living in mosaic landscape. The local greening programs can help Orthoptera conservation as well through supporting the production of these cultures. Complex landscape- and crop rotation planning, that regard the spatial and temporal distribution, and ratio of agriculture landscape elements may become an effective tool for biodiversity conservation and forming sustainable farming systems.

Re‐surveys reveal biotic homogenization of Orthoptera assemblages as a consequence of environmental change

AbstractAimBiodiversity loss is a major global challenge. While population trends of vertebrates are well documented, insect declines have not been sufficiently studied. We aim to identify changes in Orthoptera assemblages and the underlying drivers with a focus on land‐use and climate change.LocationCentral Europe.Time period2018 to 2020.MethodsWe resurveyed 199 study sites in which Orthoptera assemblages had been recorded between 1986 and 1999.ResultsOur results show a significant increase in species per site (α‐diversity), but simultaneously a homogenization of Orthoptera assemblages (decreasing Sorensen's β‐diversity). Highly mobile species significantly increased in site occupancy compared to species with low mobility. Some Orthoptera species showed significant altitudinal range shifts, including species with positive trends (i.e. expansion to higher altitudes) and negative trends (i.e. extinction at lower altitudes). Abandonment of extensively used grassland sites and the associated afforestation had negative effects on Orthoptera, underlining the importance of extensive grassland management. Protected areas had a high efficacy for conservation as trends in site occupancy were generally more positive in protected areas than in unprotected sites.Main conclusionsOur results provide insights into the patterns and drivers of orthopteran assemblage turnover, including major effects of agricultural land‐use change and climate change. These results are essential for implementing and adapting conservation action, as they show that traditional land‐use practices, protected areas and reduction of nitrogen input are important to preserve Orthoptera. The results also show that climate change is driving both range expansion and retraction of species. Therefore, insect monitoring is critical to understanding insect population trends and implementing the necessary actions.

Temperature preferences drive additive biotic homogenization of Orthoptera assemblages.

The degradation of natural habitats is causing ongoing homogenization of biological communities and declines in terrestrial insect biodiversity, particularly in agricultural landscapes. Orthoptera are focal species of nature conservation and experienced significant diversity losses over the past decades. However, the causes underlying these changes are not yet fully understood. We analysed changes in Orthoptera assemblages surveyed in 1988, 2004 and 2019 on 198 plots distributed across four major grassland types in Central Europe. We demonstrated compositional differences in Orthoptera assemblages found in wet, dry and mesic grasslands, as well as ruderal habitats decreased, indicating biotic homogenization. However, mean α-diversity of Orthoptera assemblages increased over the study period. We detected increasing numbers of species with preferences for higher temperatures in mesic and wet grasslands. By analysing the temperature, moisture and vegetation preferences of Orthoptera, we found that additive homogenization was driven by a loss of species adapted to extremely dry and nitrogen-poor habitats and a parallel spread of species preferring warmer macroclimates.

Effect of dramatic alteration of landscape structure on the Orthoptera assemblages of Transcarpathian lowland meadows (West Ukraine)

Traditional and extensively used agricultural lands maintain and protect high levels of biological diversity. This diversity is in decline due to land use intensification and abandonment. Natural and semi-natural grasslands of the Carpathian lowlands have become endangered over the 19th century. However, some remains of former wetlands have survived land use change in the Bereg Region (North-eastern Hungary and Eastern Ukraine). We surveyed Orthopterans as sensitive indicators of habitat structure and microclimate in grasslands. We identified three different Orthoptera assemblages and their character species. Although rare and especially valuable species were not found in the studied sites, the species rich remains of wetlands still protected relics of former wildlife of wetlands. Understanding the quantitative character of the assemblages, ratios of life forms and particularly co-occurrences of their character species (Chorthippus dorsatus, Leptophyes albovittata, Tettigonia viridissima and Ruspolia nitidula) and use of Grasshopper Conservation Indexes (GCI) can help to identify remaining good quality patches with highest conservation value and monitoring.Implications for insect conservationThe focused management of these habitats with reconsideration of the traditional water management can be effective practice for wetland management and Orthoptera conservation.

Data on the Orthoptera fauna of characteristic agricultural landscape in the Carpathian Lowland

Orthoptera fauna and assemblages of natural and semi-natural grasslands of the Hungarian Lowland are well-known, however, little is known about assemblages living in agricultural and anthropogenic habitats such as arable lands, roadsides, hedges, and riverbanks. Due to climate change, intensification of agriculture, and change of habitat use, these habitat types become increasingly important. To collect data on these mainly unknown habitat types, a three-year study was carried out on the Orthoptera fauna and assemblages of the firth region of the Tisza and Sajó rivers. This area was mainly unknown, and our research contributes to increasing knowledge and provides a base for further investigations. In the 40 sampling sites of the studied region, an occurrence of 30 Orthoptera species was recorded based on 2241 sampled individuals. In this study, we provide 540 new distribution data records of orthopterans that means an almost eightfold increase of the known data. Orthoptera assemblages of different agricultural habitat types showed significant differences considering both species richness and composition. Data suggested that non-cultivated habitat patches of dirt-roads, roadsides and stubble fields and even extensively used pastures, hayfields and alfalfa, red clover, and even wheat fields can preserve relatively species-rich Orthoptera assemblages. Contrary weedy sites of these cultivars and intensively used arable lands (maize, sunflower and rape fields) showed extremely low species diversity.

Orthoptera assemblages of the relict meadows of the Szernye marsh area (West Ukraine: Transcarpathia)

Orthoptera assemblages were sampled between 2012 and 2014 on six grasslands in marginal part of the former Szernye Marsh (Bereg Lowland, Transcarpathia, West Ukraine). 24 species in 1306 individuals were observed which is about the half of the Orthoptera species known from the Bereg Lowland. The bulk of the assemblages is formed by generalist chortobiont species (62.5%), while thamnobionts, connected with tall forb and/or shrubby vegetation, also reach a relatively high frequency (29.1%). According to the biogeographical composition, the Euro-Siberian species were predominating (58.3%), combined with only scarce presence of West Palearctic and Mediterranean species. The multivariate analysis did not show any clear subdivision according to the a priori vegetation types with the exception of the xeric habitats. This assemblage type were characterised by a low species number (7–12) and very high frequency of one or at least two dominant species which were common in all types of studied habitats. Although their subdominant species differed from the other two assemlage types but they could not be referred as true character species. Thus the studied xeric habitats are not such true xeric grasslands as the sandy and saline grasslands of the Pannonian lowland. The main natural value of the area is preseved by semi-natural humide and transitional habitat types, which can be conserved by yearly alternating mowing and preserving the mosaic structure with some corridors among them.

Distribution patterns of assemblages of Orthoptera on plains following an west-east gradient along the 55° N latitude in the south-eastern part of the West Siberian Plain

Distribution patterns of assemblages of Orthoptera on plains following an west-east gradient along the 55° N latitude in the south-eastern part of the West Siberian Plain

Response of Orthoptera assemblages to environmental change in a low-mountain range differs among grassland types

Grasslands are among the most species-rich ecosystems in Europe. However, their biodiversity has become increasingly threatened by land-use and climate change. Here, we analyze Orthoptera assemblage shifts between 1996 and 2017 across three grassland types in the Black Forest (SW Germany) (N = 63): (i) formerly managed wet grasslands which have been frequently abandoned in recent decades (WET) (N = 15); (ii) common pastures which are still traditionally managed by rough grazing (COMMON) (N = 29), and (iii) mesic grasslands which have recently suffered from land-use intensification (MESIC) (N = 19).Both annual and summer temperatures increased during the study period. Orthoptera assemblages strongly responded to the altered environmental conditions in the grasslands. However, effects differed clearly among grassland types. Despite a strong increase in overall species richness in common pastures, neither the Community Farmland Index (CFI) nor the Community Temperature Index (CTI) had changed. In the two other grassland types, the CFI decreased and the CTI increased.The CFI – established here for Orthoptera – helped to disentangle the effects of climate and land-use change on Orthoptera assemblage composition. Based on our study, climate warming has led to biotic homogenization of the Orthoptera assemblages of wet grasslands affected by abandonment, and mesic grasslands affected by land-use intensification towards a dominance of more widespread species. In contrast, common pastures characterized by a high heterogeneity and low-intensity management were more resilient to the effects of climate warming.

The assemblages of Orthoptera in the south-eastern part of West Siberian Plain (the Karasuk River Basin), Russia

The assemblages of Orthoptera in the south-eastern part of West Siberian Plain (the Karasuk River Basin), Russia

Effects of field margins and other uncultivated fields on Orthoptera assemblages in the mountainous paddy field area of northeast Japan

To understand how farmlands help maintain biodiversity, we investigated the relationship between habitat heterogeneity and Orthoptera community composition on multiple spatial scales. First, we determined the impact of 12 environmental variables on the Orthoptera community diversity by sampling 37 quadrats in uncultivated fields over a broad spatial scale. Canonical correspondence analysis (CCA) demonstrated that environmental parameters influenced species composition. The first two canonical axes were associated with forest cover, grass (including harvested dried grass in some cases), bare or paddy fields, and plants with tall stems. Secondly, we conducted a local-scale survey of Orthoptera assemblages in an operational farm unit consisting of paddy fields, fallow fields, marginal grass fields, and secondary forests. Eleven Orthoptera species (46%) were found exclusively on specific vegetation types. Thirdly, we carried out a habitat-scale survey to elucidate the correspondence between consecutive spatial changes in vegetation and Orthoptera community composition in a paddy field and surrounding marginal fields. Even within narrower ranges, the compositional habitat heterogeneity induced changes in the dominant Orthoptera species composition. These results indicate that a high degree of habitat segregation occurs among Orthoptera species in field margins and in uncultivated fields, and that farmland management significantly affects spatial distribution of Orthoptera.

Effects of grazing on orthopteran assemblages of Central-European sand grasslands

The effect of grazing on Orthoptera assemblages has long been the focus of research worldwide due to the high sensitivity of orthopterans to changes in vegetation structure. According to previous studies, grazing has individual, spatially-different effects on orthopteran assemblages. The current case study was carried out between 2012 and 2016 in a subarea dominated by open sandy grasslands in the Carpathian Basin. The ~70 ha study area was grazed by 250–300 sheep in 2012. In the beginning of 2014, the overgrazing pressure was overall reduced, for the most part, in the examined grassland patches. The study aimed to answer how the complete abandonment of grazing and moderate grazing influences the species richness, diversity and density of the orthopteran assemblages. Investigations in Central European sand steppes confirmed that both intense grazing and the abandonment of grazing have a detrimental effect on the structure of orthopteran assemblages: (a) the Shannon diversity index was higher on moderately grazed sites than on grazed and ungrazed ones; (b) the number of habitat specialists of sandy grasslands was higher on moderately grazed patches than in grazed habitats; and (c) the frequency of geophilic species was higher on grazed patches than on moderately grazed and grazing-abandoned ones.

Orthoptera prove good indicators of grassland rehabilitation success in the first French Natural Asset Reserve

In the last few years, legislation in more and more countries has stipulated compensation for impacts on biodiversity. France was one of the first countries to include compensation in its national law on nature preservation (1976), but habitat banking was only recently introduced into the mitigation regulatory framework. It was applied for the first time in 2008, when the first French Natural Asset Reserve was created in the plain of La Crau (Southeastern France), the last semi-arid steppe in Western Europe. This project was realized through mitigation banking and involved the ecological rehabilitation of an abandoned conventional orchard to a dry Mediterranean grassland habitat for the rare and protected steppe birds typical of this area. Here, to measure habitat rehabilitation success and validate the mitigation banking principle, we use Orthoptera as rapid and integrative indicators. Performing a six-year study (2008–2013), we assessed Orthoptera assemblages before rehabilitation (2008), when the conventional orchard was abandoned; during rehabilitation (2009); and for four years after rehabilitation (2010–2013). Three areas were considered: the area that was rehabilitated, the surrounding undisturbed steppe considered as reference ecosystem and the edge between them. The rapid recovery of typical Orthoptera assemblages measured in terms of species richness, abundance and composition confirms the successful rehabilitation of the habitat, allowing the return of steppe birds, the objective of the compensation project.

Effects of landscape and habitat quality on Orthoptera assemblages of pre-alpine calcareous grasslands

Abstract Due to the transition from traditional land use to modern agriculture throughout Europe, semi-natural grasslands are subject to severe environmental changes. Both agricultural intensification and abandonment have caused degradation, loss and fragmentation of semi-natural grasslands with adverse effects on biodiversity. We analysed the effects of landscape and habitat quality on Orthoptera in pre-alpine calcareous grasslands of the Northern Limestone Alps. At the landscape level, we focused on the effects of functional connectivity, patch size and habitat heterogeneity on Orthoptera species richness of 13 randomly selected grassland patches. At the habitat level, we studied the effects of land use on vegetation structure and microclimate as well as on Orthoptera species richness and abundance on 50 randomly chosen plots within these patches. At the landscape level, the number of Orthoptera species in well-connected pre-alpine calcareous grasslands increased with habitat heterogeneity, which was inter-related with patch size. Functional connectivity, however, had no effect on species richness. At the habitat level, species richness and abundance of Orthoptera were driven by land use together with vegetation structure and microclimate. In general, the explanatory power of our abundance models was at least twice as high as those of the species richness models. Based on the results of our study, conservation management of grassland Orthoptera should primarily focus on improving habitat heterogeneity and habitat quality within patches.

Distribution and ecology of the flightless bush-cricket Poecilimon schmidtii at its northern range margin

AbstractThe distributional patterns and ecology of the ponto-mediterranean species

Effects of ecological restoration on Orthoptera assemblages in a Mediterranean steppe rangeland

In the last century, human activities have contributed to the fragmentation and the loss of 80 % of the original surface of a Mediterranean steppe rangeland in south-eastern France. In a recent ecological restoration project, an intensively cultivated orchard of 357 ha planted in 1987 among the steppe vegetation was rehabilitated as a herbaceous habitat for steppe birds after its abandonment in 2006. In addition, three experimental restoration treatments (nurse species seeding, hay transfer; soil transfer) were applied at large scale to test the restoration of the original steppe vegetation. Our four-year study aimed to assess the effect of this rehabilitation and the restoration treatments on Orthoptera assemblages. Capturing the Orthoptera with sweep nets, we measured species richness, abundance, Shannon index, Shannon evenness, Renkonen similarity index and two community structure indices. Our results reveal no significant differences in Orthoptera species richness, abundance and diversity between control and reference steppe after 4 years, indicating that the rehabilitation and the three restoration treatments did not significantly accelerate natural recolonization. In the last year of survey, Orthoptera abundances were still significantly lower in the restored treatments than in the original steppe. Thus, future monitoring will need to determine whether abundance and structure similar to that of the reference steppe is achieved in these restored treatments.

Effects of Climate Change and Various Grassland Management Practices on Grasshopper (Orthoptera) Assemblages

Influence of different grassland management practices on Orthoptera assemblages inhabiting humid grassland areas was studied since 2003 to 2011. The examined sites were within the protected area of Balaton Uplands National Park. The physiognomy and climatic conditions of the studied habitats were similar but their land use types were significantly different. After the preliminary analyses of Nonmetric multidimensional scaling, neighbour joining clustering, and Spearman rank correlation, we examined the possible effects of such independent variables as land use (nonmanagement, mowing, grazing), microclimate (humidity and temperature), regional macroclimate (annual and monthly mean temperatures and rainfall), using General Linear Mixed Models, and canonical correlation analysis. Our results showed that the effect of grassland management practices on the organization of Orthoptera assemblages was at least as important as that of macro- and microclimate. Furthermore, grassland management could intensify the influence of several local and regional parameters. These results can help finding the most suitable type of grassland management to conserve the grasshopper assemblages.

Updated list and community structure of Tettigonioidea and Acridoidea (Insecta: Orthoptera) of the Alta Murgia plateau (Italy)

Alta Murgia calcareous plateau (southeast Italy) is thought to represent one of the most important area for Orthoptera in southern Italy, both due to its biogeographical concern and its unique richness in semi-natural dry grasslands. Since the half of the last century, no recent synthesis has been proposed for the Orthopterofauna of this area and a revision of old observations was still needed. This paper propose a reviewed list of Tettigonioidea and Acridoidea species from the Alta Murgia plateau, also providing information on local community structure and ecology. Based on the revision of previously published lists of species and on data collected during recent field works, a number of 37 species of grasshoppers and katydids is reported. The majority of species found in literature were confirmed, and six species were recorded as new for the area. Data collected during recent field works also enable to provide information about community structure, with particular focus on grassland habitat. This study also gives suggestions for replicable monitoring of Orthoptera assemblages in this area, as it is a valuable information for habitat surveillance purposes and ecosystem conservation strategies.

Temporal-Spatial Dynamics in Orthoptera in Relation to Nutrient Availability and Plant Species Richness

Nutrient availability in ecosystems has increased dramatically over the last century. Excess reactive nitrogen deposition is known to negatively impact plant communities, e.g. by changing species composition, biomass and vegetation structure. In contrast, little is known on how such impacts propagate to higher trophic levels. To evaluate how nitrogen deposition affects plants and herbivore communities through time, we used extensive databases of spatially explicit historical records of Dutch plant species and Orthoptera (grasshoppers and crickets), a group of animals that are particularly susceptible to changes in the C:N ratio of their resources. We use robust methods that deal with the unstandardized nature of historical databases to test whether nitrogen deposition levels and plant richness changes influence the patterns of richness change of Orthoptera, taking into account Orthoptera species functional traits. Our findings show that effects indeed also propagate to higher trophic levels. Differences in functional traits affected the temporal-spatial dynamics of assemblages of Orthoptera. While nitrogen deposition affected plant diversity, contrary to our expectations, we could not find a strong significant effect of food related traits. However we found that species with low habitat specificity, limited dispersal capacity and egg deposition in the soil were more negativly affected by nitrogen deposition levels. Despite the lack of significant effect of plant richness or food related traits on Orthoptera, the negative effects of nitrogen detected within certain trait groups (e.g. groups with limited disperse ability) could be related to subtle changes in plant abundance and plant quality. Our results, however, suggest that the changes in soil conditions (where many Orthoptera species lay their eggs) or other habitat changes driven by nitrogen have a stronger influence than food related traits. To fully evaluate the negative effects of nitrogen deposition on higher trophic levels it is essential to take into account species life-history traits.

Orthoptera assemblages of beech stand plots during early succession stages after clearcutting -

Open habitats in closed forests are formed by various biotic and abiotic factors. These new habitats differ from their former parent stands in light conditions and vegetation structure facilitating their colonisation by heliophilous insects. We studied interseasonal differences (2010 and 2011) in the Orthoptera assemblages on eight clearcuts in beech forests. Using a sweeping method, altogether 20 species were recorded on the clearcuts in the first year, 26 in the second. In the second year, species number and abundance were higher in all orthopterans and also in the suborder of grasshoppers (Caelifera). In the crickets (Ensifera), interseasonal differences in the species number and abundance were not significant. The species composition differed among the plots also within individual years. In the second year, the frequency increased in 22 species (84.6%) while it decreased in four. We suggest that the ground-dwelling Caelifera species are better bioindicators of the deforested plot colonisation than the arbusticolous Ensifera.