Butterfly Community Structure Research Articles

Alteration in butterfly community structure along urban–rural gradient: with insights to conservation management

BackgroundEcosystem services rendered by the butterflies are important for the sustenance of community interaction. Butterfly species have also coevolved with the host and nectaring plants. In the adult condition, they mostly rely on nectar, while in the larval condition, they feed on the leaves of their host plants. Butterfly species are sensitive to changes in environmental parameters and are considered excellent indicators of ecosystem health. The study of species diversity and richness indices aids in better ecosystem management. The present study's goal was to determine butterfly diversity in the urban–rural gradient of Purulia district, West Bengal, India, a part of the Chota Nagpur Plateau. We aim to complement crucial information on butterfly conservation management in Purulia, West Bengal, India, and other similar geographical areas with the findings of this study.ResultsIt was found that out of 3809 sampled butterflies, the individual contribution of the family Nymphalidae was the highest (51.24%), followed by Lycaenidae (18.40%), Pieridae (17.32%), Papilionidae (9.74%), and Hesperiidae (3.12%). A total of 54 butterfly species were observed in the urban–rural gradient, out of which the urban region contained 49 species, the suburban region had 32 species, and the rural region had 30 species. Significant differences were observed in butterfly abundance for the sites, seasons, and families during the study period. PERMANOVA and ANOSIM for species abundance and species presence-absence data show that all three sites are significantly different. Results Both PCoA and NMDS revealed clear differences among sites (groups) in terms of species abundance and presence-absence data. According to the findings of this study, the urban region has the highest species richness, followed by the suburban and rural regions. We discovered that urban areas have the highest butterfly abundance, followed by suburban and rural areas. Numerous butterfly species prefer the bushes dominated by Lantanacamara in the urban region with the highest species richness. Aside from this invasive weed, the site also contains Tridaxprocumbens, Catharanthusroseus, Synedrellanodiflora, and Ocimumamericanum, which are well known for being butterfly nectaring plants. In the case of the suburban region, members of the Lycaenidae family contributed the highest percentage after Nymphalidae, which was dominated by Tridaxprocumbens and Sphagneticolatrilobata, which was preferred by the members of the Lycaenidae family observed during the survey, this site also contained Ixoracoccinea, Catharanthusroseus, and Lantanacamara. This site, in terms of nectaring plants, remains homogeneous in a rural region.ConclusionsOut of 3809 butterfly individuals, the family Nymphalidae contributed the most, followed by Lycaenidae, Pieridae, Papilionidae, and Hesperiidae. Both species richness and butterfly abundance were highest in urban regions, followed by sub-urban and rural regions. The current study has shown that this particular geographic location can sustain a variety of butterfly species. However, it is important to note that conservation planning is necessary not only for the butterfly species but also for the nectaring plant species that contribute to the diversity of these insects. The conservation of butterfly species can also lead to the achievement of ecosystem services they provide.

Diversity and Community Structure of Butterflies (Lepidoptera: Papilionoidea) in The Sigolo-Golo Tourism Area, Jombang, East Java

The Sigolo-golo natural tourism area is located in the Wonosalam district, Jombang. The environment in this area is still relatively well preserved because it has a variety of vegetation and habitats. There is very little information on the community structure of butterflies (Papilionoidea) in this area, so this research is needed to find the community structure of butterflies in Sigolo-golo tourism. The method used in this research is a visual encounter survey combined with the transect method, which is to carry out direct counts of species and individuals of butterflies that are often found. The research locations were divided based on different habitat types, namely plantations, forests, and riverbanks. This study found 43 species with 358 individuals from five families. The results of the data analysis show that the diversity index value at each location is in the high category. The diversity and revealing butterflies at each location explain why the community structure in Sigolo-golo tourism is still stable and well maintained.

Determinants of Butterfly Community Structure and Composition at the Local Habitat Level: Importance of Neighboring Vegetation and Management Status: A Case Study

Exploring the determinants of biological community structure is important not only for understanding the formation of the community, but also for promoting its biodiversity conservation. We monitored butterfly communities in a grassland and woodland area of Mount Fuji, Japan, and explored the environmental factors that influenced them. Multivariate regression tree (MRT) analysis generated a 3-leaved MRT (G1, G2, and G3) and showed the total explained variation of 64.4% in the species composition. The explanatory variables discriminating between the two branches in the first node and in the second node of the MRT were neighboring plant community and management status, respectively. The neighboring plant community was related to the distribution of butterfly dietary resources and contributed a lot in determining the species composition of the community while the management status was largely related to the amount of their dietary resources, affecting the species richness and diversity. The PCA results revealed that the three key groups (G1, G2, and G3) were formed along the gradients of these two factors. Consequently, maintaining mowing management and the diversity of neighboring vegetation is very important for the continuance of butterfly community diversity and composition and the conservation of Red Listed species in the area.

The Impact of Urbanization on Taxonomic Diversity and Functional Similarity among Butterfly Communities in Waterfront Green Spaces.

Urbanization has been shown to cause biodiversity loss. However, its effects on butterfly taxonomic and functional diversity still need to be studied, especially in urban waterfront green spaces where mechanisms of impact still need to be explored. We used butterflies as indicators to study how urbanization affects their taxonomic and functional diversity and identify indicator species in different urban ecological gradient areas. From July to September 2022, we surveyed 10 urban waterfront green spaces in Fuzhou City, China. We recorded 1163 butterflies of 28 species from 6 families. First, we explored the effects of urbanization on butterfly communities and made pairwise comparisons of different urban ecological gradients (α-diversity); secondly, we looked for differences between butterfly communities across urban ecological gradients (β-diversity); finally, we investigated differences in the response of butterfly functional groups to different urban ecological gradient areas and identified ecological indicative species. This study found the following: (1) Urbanization has led to the simplification of butterfly community structure, but there are also favorable factors that support the survival of individual butterflies; (2) Urbanization has led to significant differences in butterfly communities and plant-feeding polyphagous butterfly groups; (3) Urbanization has led to differences in the functional diversity of butterfly diet and activity space groups; (4) We identified five eco-indicator species in different urban ecological gradients.

Butterfly (Lepidoptera: Papilionoidae) diversity and structure community in Lumajang, East Java, Indonesia

Abstract. Millah N, Leksono AS, Yanuwiadi B. 2023. Butterfly (Lepidoptera: Papilionoidae) diversity and structure community in Lumajang, East Java, Indonesia. Nusantara Bioscience 15: 118-128. Lumajang is one of the district in East Java, Indonesia with an area of around 1,790.90 km2 with various ecosystems. Unfortunately, several ecosystems in Lumajang have been degraded, affecting biodiversity, especially butterflies. The aim of this study was to analyze the structure of butterfly communities in Lumajang and analyze the species as bioindicators. The study was conducted in 5 habitats: Village, Agriculture, City Park, Community Forest, and Conservation Forest. The butterfly sampling method in this study was an Active Visual Survey using the Transect Pollard Walk; environmental factors were also measured during the study (temperature, humidity, light intensity, wind velocity, and altitude). The butterfly diversity and the measurement of environmental factors were analyzed for correlation using the Principal Component Analysis (PCA). The results of the study consisted of 124 species. Several were endemic species (Cyrestis lutea (Zincken, 1831), Ypthima nigricans (Snellen, 1892), Parantica albata (Zincken, 1831), Mycalesis sudra (Felder, 1867), and Pachliopta adamas (Zincken, 1831)), then protected species (Troides helena (Linnaeus, 1758), Troides cuneifera (Oberthür, 1879), and Troides amphrysus (Cramer, 1779)). The Shannon-Wienner diversity index values from highest to lowest are Community Forest (3.52), Conservation Forest (3.32), City Park (2.98), Village (2.79), and Agriculture (2.29). The results can be used as basic data and are expected to support butterfly conservation strategies in Indonesia, especially in Lumajang, East Java, Indonesia.

The Habitat Network for Butterfly Communities of the Alta Murgia National Park (Apulia, Italy)

Habitat networks can help to make habitats more resilient and assist species survival in a fragmented landscape and changing climate. Butterflies are one of the main indicators of diversity due to their high sensitivity to environmental changes. In the context of sudden and unpredictable environmental changes, protection strategies for butterflies at risk of extinction should consider the exact distribution of these species, as well as the various threats to which each of them is subjected. About 290 species of butterflies are reported in Italian fauna, and 120 of them are recorded in Apulia (Southern Italy). In the Alta Murgia National Park (AMNP) (Apulia Region, Italy), screening was performed to study the relationships between area/landscape composition and diurnal butterfly community structure. Representative semi-natural habitats of Alta Murgia buffering productive crops were selected to set up transects/paths along dry grasslands, oak forests and pine forests. Monthly samplings were performed for one year. During the survey, 909 specimens from 53 species were collected. The highest values of butterfly’s abundance and richness were recorded in dry grasslands. A strong positive correlation between butterfly abundance and air temperature was registered (Pearson correlation: r = 0.8; p < 0.001). Melanargia arge, endemic in central-southern Italy and considered threatened in Europe (Annexes II and IV—Habitats Directive), was registered in each habitat. The biodiversity indices (Chao 1, Shannon and Simpson) for each habitat were high and similar to those in protected areas of Sicily. The connected landscape is important for generalist or open-habitat specialists, and large remnants are key for disturbance-sensitive and threatened taxa. The presented evidence can provide useful information on butterfly conservation in the AMNP and for the management and conservation of characteristic landscapes of Alta Murgia.

Local habitat characteristics determine butterfly diversity and community structure in a threatened Kihansi gorge forest, Southern Udzungwa Mountains, Tanzania

BackgroundMany species inhabiting Kihansi gorge ecosystem in Southern Udzungwa Mountains, Tanzania are threatened with extinction due to habitat loss caused by constructed hydropower plant that diverted over 90% the water off the Kihansi River. Understanding ecological correlates and structure of an animal community in perturbed ecosystems is an important way to enhancing species conservation particularly in this system, where several species are already threatened with extinction. This study assessed influences of local habitat characteristics on the butterfly abundance, species richness and diversity and examined how the butterfly community structures across three structurally heterogeneous habitats in the Kihansi gorge forest. Butterfly abundance data were collected using baited traps and measured environmental variables in the field, where trapping occurred. To understand the diversity and butterfly richness, these parameters were computed under Primer software. Non-metric multidimensional scaling and analysis of community similarity were used to analyse the butterfly community structure. Furthermore, the generalized linear models (GLM) were used to assess how the measured variables explained observed species diversity, abundance, and richness.ResultsIn total, 72 species of butterfly in five families were recorded. Butterfly species diversity and richness did not vary across the habitat types or elevation gradient but showed strong correlation with some habitat characteristics. In addition, there was evidence of butterfly communities structuring into distinct groups that showed greater separation associated with the habitat characteristics they utilise. Furthermore, across the study area, butterfly species diversity increased significantly in high canopy and in trees with smaller DBH and at lower ground cover. Similarly, abundance significantly increased in the woodland and wooded grassland habitats, where there was high canopy and where tree density was high. Furthermore, butterfly species richness was strongly positively associated with high canopy cover and mostly increased in sites closer to water source.ConclusionFirst, this study shows strong positive correlation between the habitat characteristics and butterfly species and community structure, suggesting strongly that maintaining habitat quality should be a priority in conserving the butterfly communities in Kihansi. Second, conservation of environmental disturbance indicator butterfly taxa which are also endemic and rare is worthy of concern under the ongoing human-induced threats in the area. It is appropriate time that the Tanzania government should declare the Kihansi gorge forest among existing protected areas to secure effective conservation of biological diversity in this threatened ecosystem. Third, the ants–butterfly symbionts and their links to the potential lichen depletion are still unclear, and thus future research should explore the trophic cascades of depleting habitat quality on the endemic and rare butterfly species in the Kihansi gorge.

Associations of butterflies across different forest types in Uttarakhand, western Himalaya, India: implications for conservation planning

Champion & Seth classified Indian forests into different ‘forest types and sub-types’, based on similarity of dominant vegetation and structural arrangement of species in each. However, it is not known if the species composition and community structure of butterflies is also different in each forest sub-type. If this is the case then each forest sub-type harbouring unique species can be taken as units of conservation on a sub-regional scale. The present study assesses for the first time the species composition and community structure of butterflies across 20 different and prominent ‘forest sub-types’ found across the state of Uttarakhand, western Himalaya. Data collected over eight years (2006–2009; June 2012; 2017–2020) using random seasonal sampling covering 307 transects revealed 370 butterfly taxa. Hierarchical clustering of butterfly abundances revealed seven different butterfly communities spread over 19 forest subtypes. Of these four forest sub-types (3C/C2a moist Shiwalik sal forest; 12/C2c moist temperate deciduous forest; 12/C1a ban oak forest; & 3C/C2c moist Terai sal forest) were identified as most important as they hold most of the butterfly diversity of the state including 58 rare taxa identified according to ‘rarity’ out of the total. GIS based mapping of these 58 priority species over laid on the protected area network and forest cover distribution in the state revealed many forested sites outside the PA network supporting these rare taxa. These sites along a physio-geographical gradient with important forest sub-types and rare taxa can be recommended and listed as new sites for conservation in the state.

Butterfly diversity throughout Midnapore urban area in West Bengal, India

Butterflies have always attracted attention due to their unique colourations. As most butterflies are highly specific in their niche utilisation, abundance of the species in a locality may advocate status of ecosystem functioning and environmental health. In recent times, different anthropogenic activities and unscientific management of nature have resulted in a decline of butterfly communities at a rapid rate. The objective of the present study is to study butterfly diversity in and around Midnapore Town, West Bengal, India. A total of 82 butterfly species belonging to six families were recorded during the two years of the study period. Of the six families Nymphalidae is the most abundant family comprising 42.54% of the total population followed by Lycaenidae (22.5%), Pieridae (19.03%), Papilionidae (8.58%), Hesperiidae (7.24%), and Riodinidae (0.11%). Different diversity indices, Lorenz curve, Whittaker plot, and Gini index show high diversity in the butterfly community structure. As Midnapore Town is the connecting area between the plains of Bengal and Chota Nagpur Plateau, the present study may be the baseline for further ecological, environmental, and conservation studies.

Resource availability drives trait composition of butterfly assemblages.

How species respond to environmental change is a fundamental question in ecology and species traits can help to tackle this question. In this study, we analyze how the functional structure of species assemblages changes with selected environmental variables along an elevational gradient. In particular, we used species traits of local butterfly communities (body size, voltinism, overwintering stages, and host specificity) in a national nature reserve in China to assess the impacts of temperature, net primary productivity, and land use. Our results show that productivity, measured as NDVI, had a stronger influence on the functional community structure of butterflies than temperature. Within the butterfly assemblages, net primary productivity mainly affected body size and supported few but large species. Length of vegetation period demonstrated dominating effects on the functional structure of local butterfly assemblages. However, an observed increase in dietary generalists with longer vegetation periods contradicted expectations based on niche breadth hypothesis, that more stable conditions should favor specialists. Furthermore, the general positive impact of vegetation period on species abundances differed considerably among functional groups. Only the group containing species hibernating as egg decreased with the length of vegetation period. Our results suggest that trait associations are instructive to explain environment-herbivore relationships, that resource availability can predominantly influence the functional composition of herbivore assemblages, and that conservation priority should be given to specialist butterfly species overwintering as egg, especially in the face of global warming.

Long-term monitoring of Menorcan butterfly populations reveals widespread insular biogeographical patterns and negative trends

A number of studies analysing the structure of butterfly communities on Mediterranean islands have confirmed the well-established pattern of a current decrease in species richness in island communities. However, these studies generally lack quantitative data on butterfly population densities across habitats and over time. This precludes testing the hypotheses of ecological release, niche expansion and density compensation in island populations and their links to the presence of fewer competitors and/or predators. Here we use long-term monitoring data on butterfly populations from five sites on Menorca (Balearic Islands) and 20 sites from continental Catalonia (NE Spain) to test several hypotheses regarding island biogeography. We first confirm that island butterfly assemblages are not only impoverished versions of their continental counterparts but also have an over-representation of habitat generalists and highly mobile species. On the other hand, we did not find a consistent phenomenon of niche expansion and density compensation was only found for Celastrina argioulus and Gonepteryx cleopatra. Given the absence of habitat specialists on islands and the severe population declines taking place amongst specialist species on mainland Catalonia in the past two decades, we expected to detect more positive trends in island butterfly communities. Instead, we noted widespread declines, comparable to those previously recorded on the continent. Both the extension of the summer drought on Menorca and general habitat degradation due to the abandonment of cattle and sheep grazing may be responsible for these general declines.

Roads affect the spatial structure of butterfly communities in grassland patches.

Roads may have an important negative effect on animal dispersal rate and mortality and thus the functioning of local populations. However, road verges may be surrogate habitats for invertebrates. This creates a conservation dilemma around the impact of roads on invertebrates. Further, the effect of roads on invertebrates is much less understood than that on vertebrates. We studied the effect of roads on butterflies by surveying abundance, species richness and composition, and mortality in ten grassland patches along high-traffic roads (∼50–100 vehicles per hour) and ten reference grassland patches next to unpaved roads with very little traffic (<1 vehicle per day) in southern Poland. Five 200-m transects parallel to the road were established in every grassland patch: at a road verge, 25 m from the verge, in the patch interior, and 25 m from the boundary between the grassland and field and at the grassland-arable field boundary. Moreover, one 200-m transect located on a road was established to collect roadkilled butterflies. The butterfly species richness but not abundance was slightly higher in grassland patches adjacent to roads than in reference grassland patches. Butterfly species composition in grasslands adjacent to roads differed from that in the reference patches. Proximity of a road increased variability in butterfly abundances within grassland patches. Grassland patches bordering roads had higher butterfly abundance and variation in species composition in some parts of the grassland patch than in other parts. These effects were not found in reference grassland patches, where butterfly species and abundance were more homogenously distributed in a patch. Plant species composition did not explain butterfly species. However, variance partitioning revealed that the presence of a road explained the highest proportion of variation in butterfly species composition, followed by plant species richness and abundance in grassland patches. Road mortality was low, and the number of roadkilled butterflies was less than 5% of that of all live butterflies. Nevertheless, the number and species composition of roadkilled butterflies were well explained by the butterfly communities living in road verges but not by total butterfly community structure in grassland patches. This study is the first to show that butterfly assemblages are altered by roads. These results indicate that: (1) grassland patches located near roads are at least as good habitats for butterflies as reference grassland patches are, (2) roads create a gradient of local environmental conditions that increases variation in the abundance of certain species and perhaps increases total species richness in grassland patches located along roads, and (3) the impact of roads on butterflies is at least partially independent of the effect of plants on butterflies. Furthermore, (4) the direct impact of road mortality is probably spatially limited to butterflies living in close proximity to roads.

Relative contribution of neutral and deterministic processes in shaping fruit-feeding butterfly assemblages in Afrotropical forests.

The unified neutral theory of biodiversity and biogeography has gained the status of a quantitative null model for explaining patterns in ecological (meta)communities. The theory assumes that individuals of trophically similar species are functionally equivalent. We empirically evaluate the relative contribution of neutral and deterministic processes in shaping fruit‐feeding butterfly assemblages in three tropical forests in Africa, using both direct (confronting the neutral model with species abundance data) and indirect approaches (testing the predictions of neutral theory using data other than species abundance distributions). Abundance data were obtained by sampling butterflies using banana baited traps set at the forest canopy and understorey strata. Our results indicate a clear consistency in the kind of species or species groups observed at either the canopy or understorey in the three studied communities. Furthermore, we found significant correlation between some flight‐related morphological traits and species abundance at the forest canopy, but not at the understorey. Neutral theory's contribution to explaining our data lies largely in identifying dispersal limitation as a key process regulating fruit‐feeding butterfly community structure. Our study illustrates that using species abundance data alone in evaluating neutral theory can be informative, but is insufficient. Species‐level information such as habitat preference, host plants, geographical distribution, and phylogeny is essential in elucidating the processes that regulate biodiversity community structures and patterns.

Diversity and density of butterfly communities in urban green areas: an analytical approach using GIS.

Urbanization is one of the leading causes of habitat loss, habitat degradation, and fragmentation. Urban development negatively affects biodiversity. We clarified changes in butterfly communities due to urbanization in urban green areas. Intotal, 59 species and 1,465 individuals of butterflies were observed in the four urban green areas -Namsan Park(NS), Ewha Womans University (EW), Bukseoul Dream Forest (BD), and Hongneung Forest (HF) -anda natural forest, Gwangneung Forest (GF). The categories of land use around the study sites were determined based on GIS data. Species richness and density of niche breadth and habitat type in the four urban green areas differed mostly from those in GF. Estimated species richness and species diversity (H')in the four urban green areas were significantly lower than those in GF. Species richness and density of forest interior species and specialist species were positively correlated with paddy, field, and forest, whereas those of forest interior species and specialists were negatively correlated with urban area and road. Species composition and community structure of butterflies in the four urban were differed from those in GF. Theseresults suggest that decreases in paddy, field, and forest associated with the increased urban area and road negatively influenced species composition and changed butterfly communities.

Short-term effects of fire on Papilionoidea (Lepidoptera) communities: a pilot study in Mediterranean maquis shrubland

In the Mediterranean landscape fires are common, sometimes arising due to human activity. Fire influences the amount of sunlight that reaches the ground, thus affecting the diversity and distribution of animal and plant species. In this study, we analysed the effect of fire on butterfly diversity at the Site of Community Importance (SCI) “Monti di Lauro” (IT8040013) in southern Italy (Campania). The area covers 7040 ha and is mainly characterised by Mediterranean maquis and woody vegetation. We compared the flight activity of butterflies before and after a fire incident in October 2008. Weekly transects were made from April to September in 2008 and 2009. From the transect data, we calculated several diversity indices. We surveyed 55 species and 5052 individuals (2008: 43 species, 1764 individuals; 2009: 49 species, 3288 individuals). Inter-year comparisons showed that richness was significantly lower in 2008 than in 2009, as well as the abundance; the evenness index was significantly higher in 2008 than in 2009. Intra-year comparisons before fire (2008) showed significant differences among months in all indices analysed, whereas after fire (2009), only evenness differed significantly. Our results show that after fire in the Mediterranean maquis, a rapid change in butterfly community structure occurred, increasing both species and individual abundance. Nevertheless, a lower evenness indicates a less balanced butterfly community after fire. Notably, Melanargia arge, a protected species by the Habitats Directive, was not observed following the fire.

Microclimate Variability Significantly Affects the Composition, Abundance and Phenology of Butterfly Communities in a Highly Threatened Neotropical Dry Forest

Abstract In temperate areas, microclimate is a key factor affecting the population dynamics of insects, but very few studies have examined the potential significance of microclimate in diverse tropical insect communities. We quantified the diversity and structure of butterfly communities in 2 different microhabitats, over seasons, and examined which abiotic (microclimate) and biotic (vegetation structure) components affected community composition. The study was performed from Jun 2009 to May 2010 at a dry forest in Ecuador, a globally threatened habitat with high levels of endemism. Two transects were established, one in each microhabitat, where baited traps were located in the understory and canopy to record butterfly species abundance. Humidity and temperature were recorded during the sampling period and vegetation variables were measured. A total of 3,731 individuals representing 93 species were collected. Higher species richness and abundances were found during the wet season. Linear regression models...

Distribution of Satyrini (Lepidoptera, Nymphalidae) in Rio Grande do Sul State, southern Brazil

AbstractKnowledge of species distribution is important for effective conservation measures. Considering that habitat features and abiotic factors can influence local community structure of butterflies, this study aimed to verify the existence of a pattern in the distribution of Satyrini in southern Brazil. For this objective, we updated the regional Satyrini species list based on field studies and literature, resulting in a total of 54 species. For those studies that presented clearly defined sampling sites, we analyzed the faunal similarity by site and by phytoecological region and verified the influences of environmental (altitude, average annual temperature and precipitation, and phytoecological region) and spatial variables (PCNM) in species distribution. We analyzed 156 records of 40 species at 14 sites and eight phytoecological regions. Environmental variables—namely, differences in temperature and phytoecological region—and spatial position proved to effect the distribution of Satyrini in southern Brazil. We thus urge that the future Conservation Units should be well spaced and properly distributed through environmentally distinct units in the landscape, representing different phytoecological regions. These conclusions shall provide subsidies to biodiversity conservation.

Directional temporal shifts in community structure of butterflies and ground beetles in fragmented oligotrophic grasslands of Central Europe

Oligotrophic calcareous grasslands are among the most species-rich habitats in temperate Europe. Land use changes caused a severe decline of these species-rich grasslands over the last decades. Today, these ecosystems exist as highly isolated and small remnants being threatened by abandonment, afforestation and the transformation into agricultural land. Local conservation activities caused changes in habitat structures within such oligotrophic calcareous grasslands and their often isolated character may have led to stochastic species extinctions due to population fluctuations. In this study we focus on potential changes of grassland biota over the past decades. We analyse retrospective species inventories (14 for carabid beetles and 7 for butterflies) from calcareous grasslands located in western Germany with adjoining parts of Luxembourg over a period from 1972 to 2011. Our data indicate two distinct temporal cohorts (past versus present) that differ strongly in the composition and structure of carabid beetles and butterfly communities. Patterns of species co-occurrences tended to be segregated in the past communities while the co-occurrences in recent communities were either random or aggregated. β-Diversity increased with time. Our results indicate a temporal shift from past communities dominated by species interactions towards recent neutral assemblages. These changes might be caused by diverging conservation management being restricted to local sites. This resulted in a higher diversity of environmental structures combined with a loss of grassland habitats and declining matrix permeability. However, we detected no loss of rare carabid beetles, while butterflies showed severe extinctions of species with specific habitat demands, high endangerment and/or low dispersal behaviour. These trends let us argue that carabid communities mirror local changes in habitat structure (caused by conservation action), while butterflies show additional effects due to environmental stochasticity, local extinctions and a subsequent lack of re-colonization from adjoining populations.

Recent trends in butterfly populations from north-east Spain and Andorra in the light of habitat and climate change

Although butterfly declines have been reported across Europe, no assessment based on detailed quantitative data has ever been made for any extensive area in the Mediterranean Basin. In 1994, a Butterfly Monitoring Scheme was launched in Catalonia (NE Spain), and in 2005 a similar, albeit much smaller, scheme started in the neighbouring Pyrenean country of Andorra. Here we provide a first thorough assessment of butterfly trends in both areas for the last 15 years. Several patterns emerged, above all a worrying decline of a substantial part of the fauna. It was also evident that habitat specialists are experiencing greater declines than habitat generalists, thereby butterfly communities becoming progressively dominated by common species. However, habitat indicators based on characteristic species also revealed that trends are actually associated with habitat types, grassland and scrub specialists declining strongly but woodland specialists showing a marginal increase. These differences are certainly related to profound landscape changes, mainly a dramatic reduction of semi-natural grasslands and open Mediterranean scrub, and a major increase in woodlands. The general effect of climatic warming on butterfly populations was investigated by using the temperature community index (CTI) approach. The thermal structure of butterfly communities remained very stable over time, except in one case where, contrary to the expectations, a significant negative trend in the CTI was noted. However, this surprising result can be explained by taking into account the above-reported pattern of butterfly communities becoming dominated by common species, characterized by low thermal indices in comparison with declining Mediterranean specialists.

Temporal abundance patterns of butterfly communities (Lepidoptera: Nymphalidae) in the Ecuadorian Amazonia and their relationship with climate

Tropical insects show temporal changes in their abundance and climate is one of the most influential factors. For tropical butterflies, few studies have quantified this relationship or analyzed changes in community composition and structure throughout time. Communities of butterflies attracted to rotting-carrion bait in one area of the Yasuni National Park, in Ecuadorian Amazonia were examined for these relationships. Butterfly communities in three different strata of the forest were sampled over 13 months using traps with rotten shrimp bait. In total, 9236 individuals of 208 species were collected between April 2002 and April 2003. The composition and structure of butterfly communities showed significant variation during the survey with a constant replacement of species throughout the year. Additionally, these communities had the highest species richness and abundance during the months with high temperatures and intermediate precipitation. Despite relatively low variation, temperature was the most significant climatic factor explaining differences in butterfly richness and abundance throughout the year. This significant response of butterfly communities to slight temperature variations reinforce the need of temporal studies to better predict how tropical butterfly populations will respond to predicted climate change.