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Grainger MJ, Garson PJ, Browne SJ, McGowan PJK, Savini T. Conservation status of Phasianidae in Southeast Asia. Biological Conservation 2018, 220, 60–66. Copyright: © 2018. This manuscript version is made available under the CC-BY-NC-ND 4.0 license DOI link to article: https://doi.org/10.1016/j.biocon.2018.02.005 Date deposited: 13/02/2018 Embargo release date: 08 August 2019 This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International licence Newcastle University ePrints - eprint.ncl.ac.uk 1 Abstract 2 Local and regional extirpations of individual species, typically high profile cases, are 3 now well documented, leading to calls for urgent action for particular species in 4 specific locations. There is a need to broaden our assessments of extinction to identify 5 landscapes that contain high proportions of threatened species and therefore, how 6 more holistic species conservation responses might be developed. The conservation 7 status of species is especially concerning in Southeast Asia and within the region, the 8 avian family Phasianidae affords the opportunity to develop an approach for 9 examining species richness and extinction probability for an entire family at landscape 10 scale. There are 42 pheasant, partridge and quail species in the region and 77 % of 11 Southeast Asia encompasses the geographic range of at least five species. Due to high 12 levels of uncertainty about how species respond to anthropogenic threats, we created 13 an expert elicited Bayesian Belief Network to explore survival prospects using 14 publically available data on IUCN extinction probability categories, proxies of threat 15 (effects of hunting, forest loss and protected area effectiveness) and species 16 geographic ranges to assess where the overall risk to survival was highest. 17 Western Myanmar, Central Indoburma (Thailand/Myanmar), the Annamite mountains 18 and Central Vietnam lowlands, Peninsular Malaysia, Sumatra and Borneo are priorities 19 for avoiding large numbers of extinctions of phasianids. This assessment will be 20 strengthened by more detailed data on intensity of hunting pressure across the region, 21 and variation in species’ tolerance to human disturbance. Strategically, therefore, 22 conservation and research should be targeted towards these landscapes. 23 24 25 Keywords: Aichi Target 12, extinction probability, Galliformes, protected area 26 effectiveness, forest loss 27 28 Introduction 29 The loss of biodiversity in Southeast Asia (Sodhi et al. 2010, Hoffmann et al. 2010) 30 has reached the point where urgent action is needed if a substantial and imminent 31 increase in species extinctions is to be avoided (Duckworth et al. 2012). At present, 92 32 out of 3807 birds and mammals are listed as Critically Endangered in the region 33 (IUCN 2016) representing a clear challenge to meeting the Convention on Biological 34 Diversity’s Aichi Target 12 of avoiding species extinctions and reversing the decline 1 35 of those species that are most threatened 36 (https://www.cbd.int/sp/targets/default.shtml). There are now many examples of local 37 and regional extirpations and probable or functional extinctions amongst individual 38 vertebrate species across Southeast Asia (e.g. Javan rhinoceros Rhinoceros sondaicus 39 annamiticus in Vietnam: Brook et al. 2012; Tiger Panthera tigris in Cambodia: 40 Goodrich et al 2015, Green Peafowl Pavo muticus in Peninsular Malaysia: McGowan 41 et al. 1999, Gurney’s Pitta Pitta gurneyi in Thailand: Round 2014), and the demise of 42 such iconic species inevitably draws attention. 43 44 In order to make meaningful progress towards Aichi Target 12 (and whatever species 45 target replaces it in 2020), there is a need to take a more strategic approach to 46 determining where action to avoid widespread species extinctions is most needed. 47 Understanding where such ‘hotspots’ of extinction are likely to be is important in 48 order to provide an objective analysis of the impact of anthropogenic pressures arising 49 in diverse contexts across the whole region, countering the attention given to a few 50 high profile species in particular countries. A broader assessment may indicate where 51 deeper problems lie for a wide range of species. Such an assessment should consider 52 species richness, the extinction probability of each species and additional factors that 53 will influence their survival prospects (such as the effectiveness of protected areas 54 that they occur in and habitat change) and would identify landscapes where 55 particularly high numbers of species face extinction. Here, we start that process in 56 Southeast Asia by identifying landscapes where the survival prospects of an 57 ecologically diverse, highly threatened taxonomic group are of especial concern. 58 59 One group that has a relatively large proportion of species with high extinction 60 probability is the avian Order Galliformes (e.g. pheasants, partridges and quails). 61 Whilst 13.2% of the 10,424 bird species are listed as threatened with extinction on the 62 IUCN Red List, 25% of the 308 Galliformes species in the world are so listed (IUCN 63 2016). For Southeast Asia the situation is similar with 10% (of 2696) of all bird 64 species and 27% of the (76) Galliformes species listed as threatened with extinction. 65 Although the status of individual species has been assessed against the IUCN Red List 66 Criteria (IUCN 2016), there is no overall analysis of the conservation challenges 67 facing the family. This hampers the broader scale understanding of how best to take 68 immediate steps that would have the widest benefit. Species in the Galliformes family 2 69 Phasianidae are subject to a range of human pressures, both direct and indirect. The 70 proportionally high degree of threat facing this group is largely a consequence of the 71 extent to which direct exploitation adds to the pressures from habitat change. The 72 Phasianidae does, therefore, offer insights into the survival prospects of species facing 73 a range of human pressures, across all major habitats throughout Southeast Asia. 74 75 Data on species responses to pressures are very limited, so we are reliant on inference 76 from what little data we do have. Using a Bayesian Belief Network (BBN) allows us 77 to make logical, adaptable, repeatable and transparent decisions on where best to 78 focus our resources in the region (Marcot et al. 2001) and it enables us to propose a 79 framework of how pressures on species interact to affect their survival prospects. We 80 use that approach here in order to assess where pressures on the avian family 81 Phasianidae are resulting in the highest level of threat across the region. Specifically, 82 we: 1) define areas in the region where family species richness and its extinction 83 probability levels, based on IUCN categorisation, are highest; 2) combine information 84 on hunting, forest loss and protected area effectiveness to assess the potential risk 85 factors that species in the family face and that is not reflected in current Red List 86 assessments; and 3) incorporate information from objectives 1 and 2 to identify 87 priority areas where to focus conservation action. 88 89 Methods 90 Southeast Asia has been variously defined, but herein we include all tropical land 91 masses between the Myanmar-Bangladesh border to the west and the Wallace Line to 92 the east (excluding the tip of Kachin State in northern Myanmar). Thus, the countries 93 of Brunei Darussalam, Cambodia, the western part of Indonesia, Lao People's 94 Democratic Republic, Malaysia, Myanmar, Philippines, Singapore, Thailand and Viet 95 Nam were included under our definition. 96 97 The Phasianidae species and their threats 98 The majority of Phasianidae in the region are associated with forest habitat (Table 99 S1). There has been a great deal of land transformation within the region (Koh et al. 100 2013), with ongoing massive deforestation highlighted as a major cause of local 101 extinctions (Sodhi et al. 2010). Despite this, forest still dominates regional land cover, 102 with 40.6% of the total area under forest cover (FAO 2010), although pristine forest 3 103 makes up only 1.85% of this total and the integrity of the forest in these areas is 104 highly variable. 105 106 Hunting, impacting almost all remaining forest in Southeast Asia, has led to declines 107 in vertebrate populations with some local and global extinctions (Corlett 2007). 108 Phasiandae may be targeted as a source of protein, for their eggs and feathers, or may 109 be by-catch in snares targeting other species, such as mammals. We have very little 110 evidence of species’ responses to hunting in the region, but at least some are thought 111 to be quite resilient to hunting pressure where their reproductive rate is relatively high 112 (e.g. Brickle et al. 2008). A number of proxies for hunting pressure specific to 113 Galliformes have been suggested previously (Keane et al. 2005), both for specific 114 areas as well as country-level socio-economic factors shown to relate to wildlife 115 exploitation (McDonald & Boucher 2011; Bradshaw et al. 2015). 116 117 Phasianidae richness 118 We focused on the 42 Phasianidae species found in the region (Table S1) for which 119 there are global distribution data. All of these species make some use of forest habitat. 120 Data on the global distribution of Phasianidae were derived from BirdLife International 121 and NatureServe (2012). These digitised distributions were summed in the raster 122 package (Hijmans 2015) of the R programme (R Core Team 2016). We weighted each 123 species by its use of forest habitat and its IUCN status: habitat data and threat status for 124 each species was downloaded from the IUCN Red List using the letsR package (Vilela 125 and Villalobos 2015) again in the R programme.