A multi-species occupancy modeling approach to access the impacts of land use and land cover on terrestrial vertebrates in the Mumbai Metropolitan Region (MMR), Western Ghats, India

Abstract

Urbanization is one of the main drivers in the conversion of natural habitats into different land use and land cover types (LULC) which threaten the local as well as global biodiversity. This impact is particularly alarming in tropical countries like India, where~18% of the world's population live, and its ever-growing economy (i.e., industrial development) expanded urban areas by several folds. We undertook this study to examine the impacts of urbanization (i.e., LULC) on terrestrial vertebrates (mammals, birds, reptiles, and amphibians) in the Mumbai Metropolitan Region (MMR), Western Ghats, India. We sampled different habitats ranged from highly disturbed urban areas to less disturbed forested areas. Multiple sampling methods such as quadrat sampling, line transect, point count, and camera trapping were used to quantify the target taxa. We used multi-species occupancy modeling in the Bayesian framework to estimate detection probability and occupancy and to assess the effect of various LULC on different species. All four groups showed a significant negative impact of increasing anthropogenic habitat cover on occupancy. Out of 213 species detected in this study, 96% of mammals, 85% of birds, 93.75% of amphibians, and 69.43% of reptiles showed a negative effect of anthropogenic habitat cover. Evidence suggests that historical and recent human disturbances could have played an important role in transforming this area from semi-evergreen and moist deciduous forest to open, scrubby, dry deciduous, and fire-prone landscape. This might be the reason for the high occupancy of open and degraded forest habitat preferring species in our study area. We recommend species-rich areas in the MMR, e.g., Karnala Bird Sanctuary (KBS) and Prabalgad-Matheran-Malanggad Hill Range (PMMHR), must be conserved through habitat restoration, ecotourism, public awareness, and policymaking.

Landscape resistance index aiming at functional forest connectivity

“…This coexistence structure between animals and anthropized environments is reported in the literature with carnivores, small mammals, and multi-species (König et al, 2020, Chapron et al, 2014, Ceia-Hasse et al, 2017, Loveridge et al 2017, Ducci et al, 2015, Bajaru et al 2020. In this perspective of heterogeneity of resistance in the landscape, the analysis of the IRP performance showed coherence and the increase of forest isolation (Fig.…”

“…Still, when we remember that while the landscape resistance is related to a point surface value, the connectivity is cumulative to movement across the dispersal surface (Cushman, Lewis, andLandguth, 2014, Krishnamurthy et al, 2016). Thus, spatial correlations are fundamental to infer the dispersion capacity of species in the environment (Bajaru et al, 2020).…”

How do terrestrial wildlife communities respond to small‐scale Acacia plantations embedded in harvested tropical forest?

“…By jointly analyzing data from multiple species, community occupancy models increase the precision of parameter estimates for rare species by ‘borrowing’ information from data‐rich species, assuming that species‐specific parameters come from a common parametric distribution, governed by community parameters (Royle & Dorazio, 2008 ). Because detection/non‐detection data is comparatively easy to collect with camera‐traps, even for rare and cryptic species in challenging terrain, fitting community occupancy models to camera‐trap data has become a widely used approach to studying the spatial ecology of terrestrial vertebrates (Bajaru et al, 2020 ; Devarajan et al, 2020 ; Rahman et al, 2021 ).…”

Bee community response to multiple stressors along a tropical urban-peri urban gradient

“…The rural agricultural landscape in the developing countries are increasingly coming under agricultural intensi cation (Hernández et al, 2016;Goulart et al, 2023) or under industrialization of different scales, generally small and medium-scale industries (Wu et al, 2023). In tropical countries there is diverse patterns and degrees of urbanization which unlike more economically developed Western countries generally lack effective urban planning and environmental protection, resulting in a more heterogenous landscape (Gebreselassie et al, 2022;Bajaru et al, 2020). Therefore, it is important to investigate urban-peri-urban gradient in tropical developing countries and how biodiversity changes along this gradient.…”