Butterfly-plant network in urban landscape: Implication for conservation and urban greening

Land snail assemblages and microhabitat preferences in the urban areas of Kolkata, India

Due to the minimal dispersal capabilities and dependency on particular microhabitat, the land snails are susceptible to anthropogenic and natural disturbances. Considering the increasing anthropogenic threats, especially in urban areas, information on species’ requirements for particular habitat is very essential for land snail conservation and sustenance. In the present commentary, diversity and distribution of small-sized land snails in relation to their microhabitat preference in urban habitats of Kolkata, West Bengal, had been carried out through the quadrat method. The information on the richness and abundance of snails and their habitat places in Kolkata, India, was used to construct a bipartite network. A total of 13 land snail species were linked with 16 microhabitats. The network indices were used to justify the specialist or generalist nature of the snail species in the context of microhabitat preference. The snail species Succinea daucina and Allopeas gracile were observed to be associated with the maximum number of habitats while species strength was highest for S. daucina. The low value of connectance (0.288, <0.5) and niche overlap (0.34), the high value of specialization index H2′ (0.58) and d′ (0.44) indicate that the snail–microhabitat interactions were highly specialized. The network ecology of snail–microhabitats illustrated in the present instance will enable the identification of preferred microhabitats, which are required for the enhancement of the population of land snails in urban areas like Kolkata, India.

The relationship between plant and butterfly richness and composition and socioecological drivers in five adjacent cities along the Mediterranean Coast of Israel

Urbanization is the land-use process that most significantly impacts flora and fauna. We conducted a multiple city comparison of two taxa to assess whether richness patterns are similar across cities and taxa. This study aimed to examine the effects socioecological factors, namely open area size, socioeconomic status and the built-up cover, on species richness and composition of plants and butterflies in five adjacent Mediterranean cities in Israel’s coastal plain. Vegetation surveys were conducted in 170 open area sites in various urban settings. In 34 of them, the presence of butterfly species was also recorded. Mixed-effect generalized linear models were used to examine the site's characteristics effect on the species richness. The identity of each city was included as a random effect in the models. Results indicated that overall plant species richness increased with patch size, whereas butterfly richness was not associated with this factor. Plant and butterfly species richness in all categories decreased with the increase in building cover, except for endemic plant species. The results demonstrate the complex contribution of urban open area patches to the biodiversity of different taxa, being conditional on their size, surrounding built-up area and socioeconomic values.

Influences of landscape structure on butterfly diversity in urban private gardens using a citizen science approach

Although urbanization is increasing worldwide, private gardens may help mitigate the impact of urbanization on butterfly diversity. We investigated how local and landscape factors correspond with the observed butterfly species diversity and species composition in Viennese private gardens. The goal is to determine the importance of private gardens for butterfly conservation. Butterfly species were observed by skilled volunteers by applying a citizen science approach. We related butterfly species numbers in private gardens with local parameters and landscape composition in a radius of 1 km around each garden. Data were analyzed using a regression approach based on generalized linear models. The butterfly species richness in private gardens was positively correlated with butterfly species richness in the surrounding landscapes. Butterfly species richness in private gardens increased with higher proportions of area relevant for butterflies in the surrounding landscape and with increasing numbers of host and nectar plant species in the private gardens. A higher proportion of wooded areas in the surrounding landscape was related with a smaller proportion of the landscape butterfly species pool being observed in the private gardens. Overall, our results could be useful in land use planning, and for future studies of how to integrate citizen science and make urban gardens more beneficial for butterfly conservation.