Conserving a Globally Threatened Species in a Semi-Natural, Agrarian Landscape
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Conserving a globally threatened species in a semi-natural, agrarian landscape H ARRIET I BBETT,CHANSETHA L AY,PONLORK P HLAI,DET S ONG,CHAMNAN H ONG S IMON P. MAHOOD and E . J . M ILNER-GULLAND Abstract Agriculture threatens biodiversity across the tropics, Introduction particularly in semi-natural grassland landscapes, where human populations are high, habitat is easily converted and or millennia humans have affected the landscapes in agriculture is prone to intensification. Over the last years Fwhich they live. In Europe, preserving semi-natural ha- intensive, commercial dry season rice cultivation has emerged bitats dominates conservation priorities, yet in the tropics as the dominant threat to the Bengal florican Houbaropsis ben- anthropogenic landscapes receive little public attention or galensis, a globally threatened bustard that breeds in the sea- conservation effort (Wright et al., ). This is especially sonally inundated grasslands of central Cambodia. Although true of grassy biomes such as grassland, savannah and floricans have been extensively monitored for years, no steppe, where landscape structure is often maintained – socioeconomic research has been undertaken to examine through complex human wildlife and ecological interac- how local livelihood activities interact with the florican. We tions (Curtin & Western, ). To date, grassy biomes conducted household questionnaires and focus groups in have largely been overlooked in conservation, viewed as de- villages in the Northern Tonle Sap Conservation Landscape graded lands or considered in terms of their potential for to gather information on household demographics, rice farm- forest restoration (Bond & Parr, ). Yet globally, nearly ing and bird hunting in protected and unprotected areas of half of Centres of Plant Diversity include grassland habitat, florican breeding habitat. We identified a significant increase and grasslands support over % of Endemic Bird Areas in dry season rice adoption by local communities since . (White et al., ). Over the next years demand to con- Dry season rice cultivation was strongly associated with agro- vert natural habitat and intensify agriculture will escalate, chemical use and rice fields directly overlapped with florican especially in developing countries (Tilman et al., ; breeding habitat, reducing habitat availability throughout the Green et al., ). Tropical grasslands, where land can be breeding season. We identified a low but significant level of converted with ease and pressure to intensify is greatest, bird hunting in grassland households (%)andrevealedade- are inherently threatened (White et al., ). Losses of mand for wild bird meat amongst local communities. Our grasslands to agriculture may exceed those of tropical rain- findings suggest an urgent need for conservation interventions forests (Hoekstra et al., ; Parr et al., ), threatening in unprotected farmland and emphasize the role of enforce- the survival of tropical grassland species and the habitats on ment and community engagement in improving protection which they depend (Wright et al., ). within protected areas. We highlight the potential of private Lowland tropical grasslands are typically found in river sector initiatives such as the Sustainable Rice Platform in rec- floodplains. In South-east Asia the Tonle Sap floodplain in onciling conservation and development for impoverished Cambodia contains the largest remaining example of season- rural communities. ally inundated grassland in the region (BirdLife International, ). This grassland is of high importance for the Bengal Keywords Agricultural intensification, Bengal florican, florican Houbaropsis bengalensis, a Critically Endangered bus- Cambodia, dry season rice, hunting, livelihoods, protected areas tard with an estimated global population of –, indivi- duals (BirdLife International, ). The species’ global distribution is restricted to two disjunct populations: India HARRIET IBBETT* (Corresponding author) Department of Life Sciences, Imperial and Nepal’s terai grasslands, and the Tonle Sap floodplain, College London, Silwood Park Campus, Ascot, UK E-mail [email protected] which supports % of the global population (BirdLife CHANSETHA LAY,PONLORK PHLAI,CHAMNAN HONG and SIMON P. MAHOOD† Wildlife International, ). In Cambodia the suitability of grassland Conservation Society, Phnom Penh, Cambodia habitat for the florican is maintained by low intensity land-use DET SONG Faculty of Agricultural Economics & Rural Development of the Royal practices such as burning, livestock grazing, and cultivation University of Agriculture, Ecoland Research Centre, Phnom Penh, Cambodia and fallowing of traditional wet season rice (Gray, ). E. J. MILNER-GULLAND Department of Zoology, University of Oxford, Oxford, UK These practices mimic functions once provided by now ex- *Present address: Department of Zoology, University of Oxford, The Tinbergen tinct megafauna (Packman et al., ). Building, South Parks Road, Oxford, OX1 3PS, UK † Since the Tonle Sap grasslands have been subject to Also at: Research Institute for the Environment and Livelihoods, Charles – Darwin University, Darwin, Northern Territory, Australia rapid land-use change. In grassland was esti- Received September . Revision requested October . mated to cover % of the floodplain but by %of Accepted December . First published online May . this natural grassland cover had been lost, primarily as a This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, Downloadeddistribution, from https://www.cambridge.org/core and reproduction in any medium,. Open provided University the originalLibrary, work on 11 is May properly 2019 cited. at 17:44:28, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/termsOryx, 2019, 53(1), 181–191 ©. https://doi.org/10.1017/S00306053160017082017 Fauna & Flora International doi:10.1017/S0030605316001708 182 H. Ibbett et al. result of aggressive scrub expansion and agricultural aban- used novel methods to provide the first estimates of the donment by inner-floodplain communities (Packman et al., prevalence of bird hunting in the Tonle Sap grasslands. ). Since the loss of grassland has been com- We also explored people’s knowledge of the presence of pounded by the emergence of dry season rice, a form of in- wild birds and their protection status. This study provides tensive, irrigated rice cultivation that relies on the the first holistic understanding of recent change in this construction of large-scale dam and canal networks semi-natural, agrarian landscape, which includes both pro- (Packman et al., ). Dry season rice expansion was ini- tected and unprotected grasslands, with implications for tially driven by Economic Land Concessions (long-term planning of future conservation of the florican. land development leases) granted by the government to in- fluential urban elites (Packman et al., ). However, recent research suggests local communities have capitalized on ir- Study area rigation investments made by concessionaires and are also converting grasslands for dry season rice (Mahood & Within Cambodia floricans are confined to small, highly Hong, ), a trend that remains unquantified. Dry season fragmented populations, % of which reside in Kampong rice is now thought to be the greatest threat to florican sur- Thom, a province on the northern shore of the Tonle Sap vival, with –% population declines recorded for the lake (Packman et al., ). In Cambodia the florican is mi- Tonle Sap population since the emergence of dry season gratory; breeding in grasslands in the dry season (February– rice cultivation in (Packman et al., ), although April), and departing at the onset of monsoonal rains (July/ studies suggest hunting may also threaten the species August) to dipterocarp forest – km north of the flood- (Packman, ). plain (Packman et al., ). However, if conditions are To develop effective conservation interventions, policy- suitable, floricans may remain in grasslands throughout makers and conservation managers require detailed under- the wet season (Packman, ). Floricans demonstrate standing of drivers of biodiversity loss, including knowledge natal philopatric tendencies and have complex exploded of the direct effects of human activities on ecosystems, and lek breeding systems, which means they require sizeable ter- understanding of how conservation interventions are ritories and large swathes of contiguous grassland habitat modulated through human behaviour (Milner-Gulland, (Gray et al., ). ). In the case of the florican, ecological studies have We surveyed villages located around six study sites in documented population declines and habitat loss (Gray, Kampong Thom province. Each study site was identified as ; Packman, ), yet in-depth understanding of how a current or former area of grassland breeding habitat local people use the grassland landscape and directly and in- subject to annual florican population monitoring (Fig. ). directly interact with florican populations remains limited. At the time of research, levels of protection varied across Although the livelihood activities of people living in the study sites, with four sites designated as Bengal Florican landscape were documented in (Gray, ), the rap- Conservation Areas and two sites in unprotected areas of idly evolving socioeconomic context means that these find- grassland or former