Mammals Make Use of Cashew Plantations in a Mixed Forest‑Cashew Landscape
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This document is downloaded from DR‑NTU (https://dr.ntu.edu.sg) Nanyang Technological University, Singapore. Mammals make use of cashew plantations in a mixed forest‑cashew landscape Rege, Anushka; Punjabi, Girish Arjun; Jathanna, Devcharan; Kumar, Ajith 2020 Rege, A., Punjabi, G. A., Jathanna, D., & Kumar, A. (2020). Mammals make use of cashew plantations in a mixed forest‑cashew landscape. Frontiers in Environmental Science, 8, 556942‑. doi:10.3389/fenvs.2020.556942 https://hdl.handle.net/10356/145758 https://doi.org/10.3389/fenvs.2020.556942 © 2020 Rege, Punjabi, Jathanna and Kumar. This is an open‑access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. 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Downloaded on 29 Sep 2021 11:09:42 SGT fenvs-08-556942 November 21, 2020 Time: 15:20 # 1 ORIGINAL RESEARCH published: 26 November 2020 doi: 10.3389/fenvs.2020.556942 Mammals Make Use of Cashew Plantations in a Mixed Forest–Cashew Landscape Anushka Rege1,2,3*†, Girish Arjun Punjabi4†, Devcharan Jathanna5† and Ajith Kumar6,7 1 Post-graduate Programme in Wildlife Biology and Conservation, Wildlife Conservation Society India Program and National Centre for Biological Sciences, Bengaluru, India, 2 Asian School of the Environment, Nanyang Technological University, Singapore, Singapore, 3 Earth Observatory of Singapore, Nanyang Technological University, Singapore, Singapore, 4 Wildlife Conservation Trust, Mumbai, India, 5 Wildlife Conservation Society-India, Bengaluru, India, 6 National Centre for Biological Sciences, Bengaluru, India, 7 Centre for Wildlife Studies, Bengaluru, India Edited by: Heterogeneous landscapes harboring mosaics of natural habitat and agriculture are John A. Cigliano, Cedar Crest College, United States increasingly gaining conservation focus in the tropics. While research on cash crops Reviewed by: such as coffee, rubber, and oil palm has led to an understanding of their role as Phuntsho Thinley, supplementary habitats, such has remained limited in cashew plantations despite it Ugyen Wangchuck Institute for Conservation and Environment being a cash crop of global significance. We conducted a study to understand the (UWICE), Bhutan occurrence of terrestrial mammal species in a mixed forest–cashew landscape in the William J. McShea, northern Western Ghats, India. During January to April 2016, we used trail cameras Smithsonian Conservation Biology 2 2 Institute (SI), United States to sample a total area of 25 km divided into 100 grid cells of 0.25 km each. We *Correspondence: deployed six trail cameras for a 24 h period in each grid cell and obtained photo- Anushka Rege captures of 11 species in forests, of which nine were detected in cashew plantations, [email protected]; [email protected] but most species showed low capture rates. For three of these species—Indian crested †ORCID: porcupine, sambar, and wild pig—we modeled habitat use as a function of site-specific Anushka Rege attributes. Wild pig showed a higher probability of use of cashew than forest, while orcid.org/0000-0002-8383-0258 porcupine and sambar did not show any pronounced differences between the two land Girish Arjun Punjabi orcid.org/0000-0001-5910-2421 uses. The probability of habitat use by sambar and porcupine was positively influenced Devcharan Jathanna by undergrowth but not for the wild pig. Wild pig habitat use was positively related to orcid.org/0000-0002-7962-4582 increased proximity of human settlements and increasing distance to forests, but the Specialty section: pattern was unreliable for sambar and porcupine. Our preliminary study demonstrates This article was submitted to that a subset of terrestrial mammals in the forest makes use of cashew plantations Conservation and Restoration Ecology, and highlights the need for further research in forest–cashew landscapes to assess a section of the journal conservation opportunities. Frontiers in Environmental Science Keywords: camera-trapping, conservation, Hystrix indica, Rusa unicolor, Sus scrofa, occupancy models, tropical Received: 29 April 2020 forests, Western Ghats Accepted: 26 October 2020 Published: 26 November 2020 Citation: INTRODUCTION Rege A, Punjabi GA, Jathanna D and Kumar A (2020) Mammals Make Use of Cashew Plantations in a Mixed Degradation and conversion of tropical forests to agriculture, plantations, or secondary forests Forest–Cashew Landscape. reduce their biodiversity values considerably (Gibson et al., 2011). However, increasing demands on Front. Environ. Sci. 8:556942. land resources means that there is limited scope for expanding terrestrial protected area coverage on doi: 10.3389/fenvs.2020.556942 privately owned land (Jenkins and Joppa, 2009; Venter et al., 2014). Thus, the long-term persistence Frontiers in Environmental Science| www.frontiersin.org 1 November 2020| Volume 8| Article 556942 fenvs-08-556942 November 21, 2020 Time: 15:20 # 2 Rege et al. Mammals Use Cashew Plantations of many mammalian species depends on their capacity to survive period of about 3 months (Vasconcelos et al., 2015). Although in modified landscapes and the ability of human societies to practices vary across regions, it appears that the general lack coexist with wildlife in such heterogeneous landscapes (Perfecto of intensive management could allow elements of biodiversity et al., 1997; Rosenzweig, 2003; Bhagwat et al., 2008; Gardner et al., to persist in cashew monocultures. An improved understanding 2009). Improved management of agro-plantation landscapes, of the use of cashew monocultures as wildlife habitat could especially when in proximity to native forests, is urgently required result in management guidelines to enhance wildlife persistence in the tropics to enhance their conservation value for native and may also benefit land owners through reward-based biodiversity (Azhar et al., 2011, 2013; Mone et al., 2014). certification programs. Agro-forestry plantations could play a supplementary role in The aim of this study was to understand the use of cashew conservation if managed within a mosaic of natural habitats plantations by terrestrial wild mammals from adjoining forests in (Chazdon, 2008; Chazdon et al., 2009). a mixed forest–cashew landscape. Specifically, the questions were: Occurrence and habitat use of wild mammals in tropical (1) Which terrestrial mammals are present in the mixed forest– agro-plantations can vary significantly depending on factors cashew landscape? (2) What subset of the species in the forests such as proximity to remnant forest patches, native vegetation, also use cashew? (3) How does land cover, undergrowth, distance and extent of human management or disturbance. Coffee to the forest edge, and distance to the nearest human settlement (Coffea sp.) plantations in proximity to forests and under influence the probability of habitat use by terrestrial mammals? natural shade harbor a large subset of the diversity that occurs While we initially intended to answer the latter question for all in adjoining forests (Bali et al., 2007; Bhagwat et al., 2008; the species detected, due to limitations of data, we only used Caudill et al., 2015). Palm oil (Elaeis guineensis) generally fails the three most-photographed species (Indian porcupine Hystrix to support mammalian diversity (Yue et al., 2015), but the indica, sambar Rusa unicolor, and wild pig Sus scrofa) to assess retention of riparian corridors, proximity to forested habitat, the effect of these factors on species habitat use. and undergrowth supported mammalian habitat use to some extent in oil palm (Pardo et al., 2019). Intensively managed rubber plantations (Hevea brasiliensis) also support much smaller MATERIALS AND METHODS subsets of mammalian diversity than forests (Phommexay et al., 2011; Warren-Thomas et al., 2015). This gives the impression that Study Area animal responses vary based on management regimes used within The study was conducted in an area of 25 km2 comprising production landscapes. of mixed forest–cashew plantation habitat in the Tillari region Cashew (Anacardium occidantale) is a globally dominant of Dodamarg tehsil, Sindhudurg district, Maharashtra, India. crop type that has not received adequate research attention We chose a study site within Sindhudurg district since it has in terms of supplementary habitat. Cashew trees are perennial the highest land area under cashew cultivation in Maharashtra and drought resistant, growing to adult heights of 5–14 m at 344 km2, accounting for 41.1% of Maharashtra’s cashew (Dendena and Corsi, 2014) in 7–10 years. Cashew plantations cultivation area (Sengar et al., 2012). The study area is located often have a layer of understory bushy growth, which is in the northern part of the Western Ghats and Sri Lanka global periodically weeded out to make cashew nut harvesting easier. biodiversity hotspot (Myers et al., 2000). The elevation ranges There is a crucial need to examine the role of cashew plantations from 50 to 1,030 m above sea level (Punjabi and Rao, 2017). as supplementary habitat, since the crop is grown in highly The vegetation comprises mainly of moist deciduous forests with biodiverse regions across the world with unquantified impacts semi-evergreen forests along riparian patches (Champion and on vertebrate