Effects of changes in the riparian forest on the butterfly community (Insecta: Lepidoptera) in Cerrado areas

Butterflies are widely recognized as biological indicators of habitat quality due to sensitivity to environmental changes and habitat disturbances. This study aimed to assess butterflies’ species diversity in Magombera Nature Forest Reserve (MNFR), Tanzania as indication of forest recovery from the previous disturbances. Specifically, the study aimed to assess i) current status of butterfly species richness and diversity in MNFR, and (ii) butterfly species abundance, dominance and distribution in MNFR. Data collected through line transects using sweep nets and visual observations across the forest area of 2,623 ha. Species richness computed as a total number of species in a given area, species diversity computed using Shannon-Weiner Diversity Index (H') and abundance computed as a total count of all individuals. The results indicated that a total of 155 butterfly species belonging to six families and 64 genera recorded in MNFR. Closed forest had high species richness (105) and diversity values (H' = 4.06) and Grassland has least species (46) and diversity values (H' = 3.27). Variation in vegetation composition in MNFR influence higher butterfly species richness, diversity and abundance in closed forest and open woodland than in grassland and riparian vegetation indicating the improvement of forest recovery from prior disturbances after being upgraded to nature reserve in 2018. Therefore, intensive management approaches that currently implemented by the Tanzania Forest Services Agency (TFS) at MNFR should be maintained to overcome other ecological changes. This will assure proper ecological flow within the forest and between Udzungwa Mountain National Park and Selous Game Reserve.

One of the major determinants of species richness is the amount of energy available, often measured as primary productivity. Heterogeneity of environmental variables has also been found to influence species richness. Predicting species distributions across landscapes and identifying areas that have high species richness, or vulnerable groups of species, is useful for land management. Remotely sensed data may help identify such areas, with the Normalized Difference Vegetation Index (NDVI) providing an estimate of primary productivity. We examined the relationship between maximum productivity (NDVI), heterogeneity of productivity, and species richness of birds and butterflies at multiple spatial scales. We also explored relationships between productivity, functional guilds and residency groups of birds, and vagility classes of butterflies. Positive linear relationships between maximum NDVI and number of functional guilds of birds were found at two spatial scales. We also found positive linear relationships between maximum NDVI and species richness of neotropical migrant birds at two scales. Heterogeneity of NDVI, by contrast, was negatively associated with number of functional guilds of birds and species richness of resident birds. Maximum NDVI was associated with species richness of all butterflies and of the most vagile butterflies. No association was found between heterogeneity of NDVI and species richness of butterflies. In the Great Basin, where high greenness and availability of water correspond to areas of high species richness and maximum NDVI, our results suggest that NDVI can provide a reliable basis for stratifying surveys of biodiversity, by highlighting areas of potentially high biodiversity across large areas. Measures of heterogeneity of NDVI appear to be less useful in explaining species richness.

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.

Little is known about the diversity of tropical animal communities in recently fire‐affected environments. Here we assessed species richness, evenness, and community similarity of butterflies and odonates in landscapes located in unburned isolates and burned areas in a habitat mosaic that was severely affected by the 1997/98 ENSO (El Niño Southern Oscillation) event in east Kalimantan, Indonesian Borneo. In addition related community similarity to variation in geographic distance between sampling sites and the habitat/vegetation structure Species richness and evenness differed significantly among landscapes but there was no congruence between both taxa. The species richness of butterflies was, for example, highest in sites located in a very large unburned isolate whereas odonate species richness was highest in sites located in a small unburned isolate and once‐burned forest. We also found substantial variation in the habitat/vegetation structure among landscapes but this was mainly due to variation between unburned and burned landscapes and variation among burned landscapes. Both distance and environment (habitat/vegetation) contributed substantially to explaining variation in the community similarity (beta diversity) of both taxa. The contribution of the environment was, however, mainly due to variation between unburned and burned landscapes, which contained very different assemblages of both taxa. Sites located in the burned forest contained assemblages that were intermediate between assemblages from sites in unburned forest and sites from a highly degraded slash‐and‐burn area indicating that the burned forest was probably recolonised by species from these disparate environments. We, furthermore, note that in contrast to species richness (alpha diversity) the patterns of community similarity (beta diversity) were highly congruent between both taxa. These results indicate that community‐wide multivariate measures of beta diversity are more consistent among taxa and more reliable indicators of disturbance, such as ENSO‐induced burning, than univariate measures.

Summary The use of surrogates to identify protected areas is a common practice in conservation biology. The use of top predators as surrogates has been criticized but recently a strong positive relationship was found between the presence of top predators and species diversity of several taxa. As mentioned by the authors, these striking results need to be assessed on a larger scale. We used data from the Swiss Biodiversity Monitoring Programme and the Swiss breeding bird survey to analyse the use of raptor species as a surrogate for plant, butterfly and bird species richness. For each raptor species, we compared species richness in sites where a raptor species was recorded and compared these sites with the remaining sites in which the raptor species was not recorded. For comparison we conducted the same analyses using tits Parus spp. Tits are common prey species of some raptor species and were the most species‐rich generalist genus in our data. We found little justification for a focus on top predators when identifying conservation areas. For bird and plant species richness, raptors were reasonable surrogates for high species richness but no raptor species predicted sites with above‐average butterfly species richness. The presence of tit species performed equally as well as the presence of raptor species to predict sites with high species richness of birds and plants, and performed even better for predicting high butterfly species richness. Synthesis and applications. Conservation planners using indicator species should be aware that relationships among higher taxa are complex and depend on the species group and the scale of analysis. As shown with the case of raptors, the usefulness of a biodiversity indicator can vary between adjacent areas even if the same species groups are analysed. We recommend the use of more than one indicator species from different taxonomic groups when identifying areas of high biodiversity.

This study compares the variation of richness, abundance and diversity of butterfly species along an atmospheric pollution gradient and during different seasons in the Monterrey Metropolitan Area, Mexico. Likewise, we analyse the influence of environmental variables on the abundance and richness of butterfly species and quantify the indicator species for each atmospheric pollution category. Based on spatial analysis of the main atmospheric pollutants and the vegetation cover conditions, four permanent sampling sites were delimited. The sampling was carried out monthly in each of the sites using aerial entomological nets and ten Van Someren-Rydon traps during May 2018 to April 2019. A total of 8,570 specimens belonging to six families and 209 species were collected. Both species richness and abundance were significantly different between all sites, except for the comparison between the moderate contamination site and the high contamination site; diversity decreased significantly with increasing levels of contamination. The seasonality effect was absent on species richness; however, for species abundance the differences between dry season and rainy season were significant in each site excepting the moderate contamination site. Regarding diversity, the seasonal effect showed different distribution patterns according to each order. Relative humidity, vegetation cover and three pollution variables were highly correlated with both abundance and species richness. From the total number of species found, only 47 had a significant indicator value. This study constitutes the first faunistic contribution of butterflies as indicators of the environmental quality of urban areas in Mexico, which will help in the development of strategies for the management, planning and conservation of urban biodiversity.

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.

The importance of the gravel excavation industry for the conservation of grassland butterflies

Effects of land cover and climate on species richness of butterflies in boreal agricultural landscapes

The presence of butterflies can be found in several types of habitats and can be used as an indicator of environmental conditions. Geologically, the Nglanggeran Ancient Volcano is unique and has high scientific value. It is necessary to update the butterfly diversity data to determine the diversity of butterflies at Nglanggeran Ancient Volcano. The purpose of this study was to determine the diversity, richness, evenness, and dominance of butterfly species at Nglanggeran Ancient Volcano. The exploration method was carried out to obtain data for three repetitions. There were 51 butterfly species with a total of 584 individuals, consisting of Nymphalidae (54.55%), Papilionidae (21.82%), Pieridae (20.00%) and Lycaenidae (3.64%). The index value of butterfly species diversity at Nglanggeran Ancient Volcano (2.97) was medium. The species evenness index (0.83) indicated that the species was relatively stable and evenly distributed. The richness of butterfly species was high, i.e. 6.70, suggesting that the current habitat was suitable for the life of the butterflies. The dominance index value was low, i.e. 0.12, indicating that there was no domination of certain species. The abundant species were Eurema sp. (23.12%), Ideopsis juventa (7.02%), and Catopsilia pomona (6.85%).

The ability to predict spatial patterns of species richness using a few easily measured environmental variables would facilitate timely evaluation of potential impacts of anthropogenic and natural disturbances on biodiversity and ecosystem functions. Two common hypotheses maintain that faunal species richness can be explained in part by either local vegetation heterogeneity or primary productivity. Although remote sensing has long been identified as a potentially powerful source of information on the latter, its principal application to biodiversity studies has been to develop classified vegetation maps at relatively coarse resolution, which then have been used to estimate animal diversity. Although classification schemes can be delineated on the basis of species composition of plants, these schemes generally do not provide information on primary productivity. Furthermore, the classification procedure is a time- and labour-intensive process, yielding results with limited accuracy. To meet decision-making needs and to develop land management strategies, more efficient methods of generating information on the spatial distribution of faunal diversity are needed. This article reports on the potential of predicting species richness using single-date Normalized Difference Vegetation Index (NDVI) derived from Landsat Thematic Mapper (TM). We use NDVI as an indicator of vegetation productivity, and examine the relationship of three measures of NDVI—mean, maximum, and standard deviation—with patterns of bird and butterfly species richness at various spatial scales. Results indicate a positive correlation, but with no definitive functional form, between species richness and productivity. The strongest relationships between species richness of birds and NDVI were observed at larger sampling grains and extent, where each of the three NDVI measures explained more than 50% of the variation in species richness. The relationship between species richness of butterflies and NDVI was strongest over smaller grains. Results suggest that measures of NDVI are an alternative approach for explaining the spatial variability of species richness of birds and butterflies.

We provide the first description of the effects of local vegetation and landscape structure on the fruit-feeding butterfly community of a natural archipelago of montane rainforest islands in the Serra do Espinhaço, southeastern Brazil. Butterflies were collected with bait traps in eleven forest islands through both dry and rainy seasons for two consecutive years. The influence of local and landscape parameters and seasonality on butterfly species richness, abundance and composition were analyzed. We also examined the partitioning and decomposition of temporal and spatial beta diversity. Five hundred and twelve fruit-feeding butterflies belonging to thirty-four species were recorded. Butterfly species richness and abundance were higher on islands with greater canopy openness in the dry season. On the other hand, islands with greater understory coverage hosted higher species richness in the rainy season. Instead, the butterfly species richness was higher with lower understory coverage in the dry season. Butterfly abundance was not influenced by understory cover. The landscape metrics of area and isolation had no effect on species richness and abundance. The composition of butterfly communities in the forest islands was not randomly structured. The butterfly communities were dependent on local and landscape effects, and the mechanism of turnover was the main source of variation in β diversity. The preservation of this mountain rainforest island complex is vital for the maintenance of fruit-feeding butterfly community; one island does not reflect the diversity found in the whole archipelago.

Within the BiodiverCity project in Malmö (Sweden), green structure elements were implemented aiming to support biodiversity and enhancing amenity in denser parts of the city. In this study, bumblebee and butterfly abundances and species richness were studied in 20 green structure elements in three areas in Malmö. The investigated green structure elements consisted of objects established within the BiodiverCity project and other green structure elements in their surroundings (e.g. road verges, lawns and flowerbeds). Observed bumblebee and butterfly abundances and species richness was generally low. In total, 528 bumblebees of eight species were recorded, with 97% of all bumblebees belonging to two species, Bombus lapidarius and B. terrestris/lucorum. A total of 154 butterflies from 10 species were detected, most commonly Pieris species. There were no significant differences in mean individual or species numbers (bumblebees and butterflies) between green structure elements designed to support biodiversity and conventional ones. Bumblebee species richness and abundance were positively correlated with mean cover of flowering vegetation and mean number of flowering plant species. Butterfly species richness and abundance were positively correlated with mean number of flowering plant species and size of the green structure. Observations of flower visits showed that the two groups of insects had different preferences. The results of this study show that enhancing bumblebee and butterfly diversity and abundances in densely built city areas can be challenging. To support bumblebees and butterflies more successfully, the habitat requirements of these insect groups need to be better considered from the beginning in the design of green structure elements.

Understanding and identifying butterfly species in various land uses serves a crucial eco-logical function in protecting biodiversity and improving environmental policy decisions. However, such a study on the diversity of butterflies from different land use types in and around Chebera Churchura Na-tional Park, southwestern Ethiopia, is extremely lacking. Thus, the present study aimed to quantify the species richness and abundance of butterflies in the Chebera Churchura National Park and its surroundings, which are prioritized for their conservation. Data was collected from January 2021 to June 2021 following the line transect method in the three habitat types using a standard insect net. In total, 2118 individuals representing 79 species and 38 genera belonging to five families were recorded. The Nymphalidae were the most dominant butterfly family, accounting for 45 species (57%) of the total butterflies observed, while the Heaspariidae contributed the least. Among the 79 species, 9 were very common, 32 were common, 37 were rare, and 1 was very rare. Based on butterfly species richness and composition, riverine forest had the greatest diversity and abundance with 65 species and 1028 individuals, and the least species composition was recorded in mosaic habitat with 26 species and 350 individuals, and the difference in diversity was significant. The study region was generally found to be rich in the diversity and abundance of butterflies in all three forms of land use. However, the study area is currently becoming an investment hub, and many road development projects are being planned. Ongoing human activities will devastate and harm the richness, abundance, and diversity of butterfly species. As a result, such human-induced activities need to be carefully studied to protect biodiversity.

Modelling butterfly species richness using mesoscale environmental variables: model construction and validation for mountain ranges in the Great Basin of western North America