Initiating conservation of a newly discovered population of the Endangered hog deer Axis porcinus in Myanmar

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Initiating conservation of a newly discovered population of the Endangered hog deer Axis porcinus in Myanmar
Initiating conservation of a newly discovered
             population of the Endangered hog deer
             Axis porcinus in Myanmar
                                            NGWE LWIN, MATTHEW LINKIE, ABISHEK HARIHAR, SAW SOE AUNG
                                                                       A U N G K O L I N and F R A N K M O M B E R G

             Abstract The unprecedented political and economic re-                                 Introduction
             forms taking place in Myanmar offer new opportunities
             for biodiversity conservation. They also bring new chal-
             lenges in the form of rapidly growing extractive industry                             F    or decades much of Myanmar has been inaccessible to
                                                                                                        conservation organizations because of political instabil-
                                                                                                   ity and civil unrest. International sanctions have limited in-
             and agriculture sectors that have been weakly regulated
             and are often unsustainable. The Endangered hog deer                                  vestment in government infrastructure and institutional
             Axis porcinus epitomizes many of these conservation chal-                             development, including the Forestry Department, which is
             lenges, and those facing most deer species in the Indo–                               the country’s leading agency for biodiversity conservation
             Burma hotspot. The hog deer has disappeared from large                                (Rao et al., ). However, since  Myanmar has under-
             parts of its range as a result of overhunting and intense con-                        taken sweeping political and economic reforms aimed at
             version of its floodplain grassland habitat for agriculture.                          giving foreign organizations access to the country, creating
             We report on a population of hog deer that was discovered                             political stability and decreasing government control of the
             in the Indawgyi landscape in central Myanmar in . We                              private sector (Schmidt, ). This comes at a time when
             conducted the first rigorous assessment of a hog deer popu-                           significant attention is also being focused on Myanmar for
             lation in Myanmar using an occupancy sampling protocol,                               its role as a major supply hub for illegal wildlife trade in Asia
             tested the protocol’s robustness using a power analysis, and                          (Shepherd & Nijman, ; Nijman & Shepherd, ).
             present the results to guide management intervention. The                                 Myanmar remains rich in wildlife and other natural re-
             results from our study site revealed widespread occurrence                            sources but has long and porous international borders that
             of the species, with high precision. The population map was                           are poorly enforced or equipped to tackle illegal wildlife
             then used to inform the development of a conservation                                 trade. Furthermore, overexploitation by poorly regulated
             management zone within a UNESCO Man and Biosphere                                     mining and logging industries, subsistence hunting, and con-
             Reserve around Indawgyi Lake. The importance of this                                  version of floodplains and grasslands to rice fields have de-
             population for the status of the hog deer in Myanmar re-                              pressed already stressed wildlife populations (Rao et al.,
             mains unknown because documentation of the species has                                ). These threats have had a collective, although unquanti-
             been sparse. Our survey protocol could make a significant                             fied, impact on the hog deer, which in many ways epitomizes
             contribution to addressing this knowledge gap and setting                             the conservation challenges facing wildlife in Myanmar.
             an informed agenda for conservation of the hog deer both                                  The hog deer’s habitat preference for grassland in close
             nationally and more widely across the Indo-Burma hotspot.                             proximity to wetlands often puts it in competition with
                                                                                                   farmers wishing to expand rice fields (Dhungel & O’Gara,
             Keywords Detection probability, hunting, mammal conser-                               ). It is also hunted for its meat. Over the past  decades
             vation, occupancy, South-east Asia, ungulate                                          a once widespread species ranging from the Himalayan
                                                                                                   foothills in Pakistan, Nepal and India to mainland
                                                                                                   South-east Asia has declined by . % within its
                                                                                                   South-east Asian range. This includes its complete dis-
                                                                                                   appearance from Thailand, Laos PDR and Viet Nam
                                                                                                   (Timmins et al., a). In Myanmar this once abundant
             NGWE LWIN, SAW SOE AUNG, AUNG KO LIN and FRANK MOMBERG Fauna & Flora                  species has been reduced to small, isolated populations
             International, Yangon, Myanmar
                                                                                                   (Evans, ; Timmins et al., a) and there is a lack of re-
             MATTHEW LINKIE* (Corresponding author) Fauna & Flora International,                   liable, or even current, population data for the hog deer, as
             Singapore 247672, Singapore
                                                                                                   for most other cervids and medium- or large-bodied mam-
             ABISHEK HARIHAR Panthera, New York, USA, and Nature Conservation
             Foundation, Mysore, India
                                                                                                   mals in general. Thus, the news of the discovery of a hog
                                                                                                   deer population in Myanmar by Fauna & Flora
             *Current address: Wildlife Conservation Society (WCS), Indonesia Program,
             Bogor, Indonesia. Email mlinkie@wcs.org                                               International in  was encouraging.
             Received  February . Revision requested  May .
                                                                                                       Preliminary field surveys in northern Myanmar recorded
             Accepted  June . First published online  October .                        the hog deer, using camera traps placed in grassland on the

                                                                                        Oryx, 2018, 52(1), 126–133 © 2016 Fauna & Flora International doi:10.1017/S0030605316000727
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. https://doi.org/10.1017/S0030605316000727
Hog deer conservation in Myanmar                     127

           eastern shore of Indawgyi Lake, the third largest freshwater                          grasslands and paddy fields). Hog deer sign comprised hoof
           lake in mainland South-east Asia. Based on these records a                            prints and pellets, which are unmistakable as no other similar
           conservation project was launched to produce a site action                            deer or livestock species are known to live in this area. Red
           plan, form community conservation groups to define a hog                              muntjac Muntiacus vaginalis and sambar Rusa unicolor live
           deer protection zone with village no-hunting agreements,                              outside the study area, in a nearby forest reserve.
           and increase awareness amongst stakeholders of the species’                               Within a grid cell, detection () or non-detection () of
           plight. The first important step was to collect reliable data to                      hog deer sign was recorded at four -minute intervals
           gain an understanding of the hog deer’s population status                             (sampling occasions). These replicates are considered to
           and threats to the species in the Indawgyi area, which                                be spatial because the team tried to maintain a similar
           would also provide a baseline for monitoring subsequent                               pace (,  km per hour) in each cell and avoid overlapping
           project intervention. Thus, the aims of this study were to                            with previously surveyed replicates, by not walking over a
           () design and pilot a new hog deer sampling protocol                                 previously walked trail within the same grid cell. For each
           using detection/non-detection surveys, () conduct the                                replicate the team recorded whether surveys were conducted
           first scientifically defensible population assessment of the                          off trail () or on footpaths or bullock cart paths (), as well
           hog deer in Myanmar based on the species’ occupancy,                                  as the dominant habitat type (tall grassland (elephant grass);
           and () determine future sampling design parameters.                                  grassland; burnt grassland; agricultural field, not planted; or
                                                                                                 agriculture field, planted), all of which could influence spe-
                                                                                                 cies detection probability. It did not rain during surveys, so
           Methods                                                                               the influence of this factor was not considered. Direct obser-
                                                                                                 vations of hog deer hunting and recent burning were re-
           Field methods                                                                         corded seperately for each grid cell.

           From preliminary field surveys conducted in  and 
           in the northern state of Kachin the putative boundaries of                            Data analysis
           hog deer distribution in the Indawgyi landscape were iden-
           tified based on suitable habitat, and used to demarcate a                             A spatial database was constructed for the sampling grid
           study area of  km (Fig. ). This study area is characterized                       based on three site covariates: mean proximity to nearest vil-
           by grassland located between the forested watershed hills in                          lage (Village), mean proximity to river or lake (Water), and
           Indawgyi Reserve Forest and Indawgyi Lake. Several small                              evidence of recent burning (Burn; denoted as burnt () or
           creeks flow through the grassland plain, and there are                                not burnt ()). Village and river data obtained from
           patches of paddy fields in these communal lands.                                      Myanmar Survey Department  : . topographic maps
               In Myanmar the hog deer falls under the protection of                             from  were standardized using a logarithmic transform-
           wildlife and protected areas law /. The preliminary                              ation. Sampling covariates were compiled along the surveys
           field surveys, camera trapping and interviews with the                                to denote trail/no trail and the dominant habitat type in
           local community indicated that the hog deer is solitary,                              each sampling replicate, which were constructed as categor-
           and no herds were recorded. However, in Nepal hog deer                                ical covariates for both.
           have been observed congregating during the fawning season                                 Hog deer occupancy (ψ) was estimated using models that
           or to forage on new shoot growth stimulated by anthropo-                              account for imperfect species detection (MacKenzie et al.,
           genic burning of grasslands (Dhungel & O’Gara, ). An                              ). The occupancy status of grid cells was assumed to re-
           individual’s home range is estimated to be .–. km                                main closed (i.e. constant) during the -hour sampling per-
           (Dhungel & O’Gara, ; Odden et al., ). To measure                              iod. As the detection/non-detection sequence of hog deer
           species occupancy the study area was divided into  sam-                             sign was collected during four consecutive -minute sam-
           pling units of  ×  km, which should be sufficient to encom-                         pling occasions per grid cell, a first order Markov process
           pass an individual’s home range.                                                      model was used to estimate the probability of hog deer oc-
               From a possible selection of  grid cells and considering                        currence (Hines et al., ). This model accounts explicitly
           available field resources,  cells were selected at random for                       for the potential dependence in detecting signs on consecu-
           sampling, using a geographical information system (GIS).                              tive occasions by estimating two segment-level occupancy
           Field surveys were conducted during – May , in the                             parameters (θ and θ’) and the probability of detecting
           dry season, when it is easier to encounter hog deer sign. A                           signs (P) conditional on segment-level occupancy.
           two-person team, consisting of an experienced field biologist                         However, to test for the presence of spatial non-
           and a local guide, surveyed each grid cell for a set sampling                         independence among replicates the constant model ψ(.),θ
           effort of  hours per cell. To increase detection probability                         (.),θ’(.),P(.),θπ(.) (Hines et al., ) was compared to a con-
           within a cell, the team specifically targeted locations where                         stant single-season model, ψ(.),P(.) (MacKenzie et al., ).
           sign was most likely to be encountered (e.g. animal trails,                           Candidate models were compared using Akaike’s

           Oryx, 2018, 52(1), 126–133 © 2016 Fauna & Flora International doi:10.1017/S0030605316000727
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128         N. Lwin et al.

             FIG. 1 Habitat of a newly discovered population of hog deer Axis porcinus in the Indawgyi landscape of northern Myanmar, with the
             survey grid and the locations where hog deer were recorded.

             information criterion corrected for small sample sizes                                either assumed to be constant or allowed to vary with indi-
             (AICc; Burnham & Anderson, ). All analyses were car-                              vidual or additively combined covariates, was modelled, with
             ried out in PRESENCE v. . (Hines, ).                                            ψ held in a general form for each model. After incorporating
                When choosing between a model that explicitly ac-                                  covariates influencing detection probability with the greatest
             counted for spatial dependence (Hines et al., ) and                               Akaike weight (wi), the influence of spatial covariates on oc-
             one that did not (MacKenzie et al., ), a two-step model-                          cupancy was assessed in the second step of the analysis. Here
             ling approach was used to test the effects of the covariates.                         ψ was either assumed to be constant or allowed to vary with
             Initially, the probability of detecting a sign, where P was                           individual or additively combined covariates.

                                                                                        Oryx, 2018, 52(1), 126–133 © 2016 Fauna & Flora International doi:10.1017/S0030605316000727
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. https://doi.org/10.1017/S0030605316000727
Hog deer conservation in Myanmar                     129

           TABLE 1 Effect of covariates on detection probability (P̂) of the hog deer Axis porcinus in the Indawgyi landscape of northern Myanmar
           (Fig. ).

           Model ID           Model description                                                     No. of parameters            ΔAICc1           Akaike weight           −2L2
           M.1.1              ψ(Burn + Water + Village)P(Habitat)                                    9                            0.00            0.7377                  180.02
           M.1.2              ψ(Burn + Water + Village)P(Habitat + Burn)                            10                            3.00            0.1644                  179.65
           M.1.3              ψ(Burn + Water + Village)P(Habitat + Burn + Trail)                    11                            4.66            0.0719                  177.72
           M.1.4              ψ(Burn + Water + Village)P(Habitat + Trail)                           10                            6.70            0.0258                  183.35
           M.1.5              ψ(Burn + Water + Village)P(Burn + Trail)                               7                           18.32            0.0001                  204.52
           M.1.6              ψ(Burn + Water + Village)P(Burn)                                       6                           19.28            0                       208.32
           M.1.7              ψ(Burn + Water + Village)P(Trail)                                      6                           20.15            0                       209.19
           M.1.8              ψ(Burn + Water + Village)P(.)                                          5                           20.47            0                       212.21
           M.1.9              ψ(.)P(.)                                                               2                           24.71            0                       223.73
           M.1.10             ψ(.)θ0(.)θ’(.)P(.)θ0π(.)                                               5                           27.54            0                       221.28
           
            ΔAICc is the difference between each model’s AICc and the AICc of the top-ranking model.
           
            L is the maximum log-likelihood.

           Power analysis

           Survey design recommendations were derived based on the
           ψ and P estimates obtained from the field study. Where de-
           tection probabilities varied depending on survey conditions,
           the mean of these probabilities was used in calculations.
           Firstly, the number of survey visits (K) required to deter-
           mine species presence at an occupied site with a specified
           probability was investigated. The probability of detecting
           the species at an occupied site in at least one of the visits
           is P* =  – ( – P)K, where P is the mean detection probabil-
           ity on any one visit. From this expression the number of vis-
           its (K) required to achieve a given desired P* (.) was
           derived as K = log( – P*)/log( – P) (McArdle, ; Kéry,
           ; Pellet & Schmidt, ).
               Next, variations in the survey design that facilitated the                        FIG. 2 Mean probability of detection (± SE) of hog deer in
           detection of changes in hog deer occupancy were assessed.                             various habitat types.
           The assessments were based on the occupancy and detection
           probability estimates from the study data set and assumed a
                                                                                                 deer signs were detected on  of  sampling occasions
           standard single-season, single-species sampling design in
                                                                                                 and in  of  sampling units, producing a naïve occupancy
           which S sites were sampled K repeated times (where K
                                                                                                 estimate of ..
           was determined to achieve P* = .). Based on the number
           of replicates (in our case, the number of successive  mi-
           nute surveys), the number of sampling sites needed to                                 Detecting hog deer signs Investigating the covariates that
           detect a change in occupancy rate between two surveys                                 influenced the probability of detecting hog deer signs we
           for a given power given an actual proportional change, R                              found little support for spatial dependency in detection
           (effect size), was calculated. Six effect sizes (R = , , ,                       resulting from a study design based on four consecutive
           ,  and %) at a significance level α = . were assessed                        -minute replicates. The Markovian detection model
           under the constraint that the total number of sites (S) that                          (M..) had the lowest ranking in comparison to a
           could be surveyed was  (i.e.  ×  km grid cells identified                       constant single-season model (M..; Table ). Further
           as being within the putative boundaries of hog deer distribu-                         examination of the two segment-level occupancy parameters
           tion in the Indawgyi landscape). All simulations were imple-                          (θ and θ’) highlighted non-significant dependency (θ = .,
           mented using R code developed by Guillera-Arroita &                                   % CI .–.; θ’ = ., % CI .–.). Hog deer
           Lahoz-Monfort ().                                                                 detection was strongly correlated with habitat type (M.) and
                                                                                                 there was a large difference between this model and the
           Results                                                                               constant model (ΔAICc = .). Across the model set,
                                                                                                 detection of signs was most strongly influenced by habitat
           The  sampling units were surveyed for a combined effort                             (AICc wi = .) in comparison to burning (AICc wi = .)
           of . hours, with – grid cells completed each day. Hog                            or trail type (AICc wi = .). Among the habitat types, the

           Oryx, 2018, 52(1), 126–133 © 2016 Fauna & Flora International doi:10.1017/S0030605316000727
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130         N. Lwin et al.

             TABLE 2 Hog deer occupancy (ĉ ) estimates obtained from the best model for the Indawgyi landscape of northern Myanmar (Fig. ).

             Model ID               Model description                                      No. of parameters                ΔAICc1              Akaike weight               −2L2
             M.2.1                  ψ(Water)P(Habitat)                                     7                                 0.00               0.3017                      181.66
             M.2.2                  ψ(.)P(Habitat)                                         6                                 0.50               0.2351                      185.00
             M.2.3                  ψ(Water + Burn)P(Habitat)                              8                                 1.53               0.1402                      180.19
             M.2.4                  ψ(Burn)P(Habitat)                                      7                                 1.84               0.1202                      183.50
             M.2.5                  ψ(Village)P(Habitat)                                   8                                 2.18               0.1014                      183.84
             M.2.6                  ψ(Water + Village)P(Habitat)                           7                                 2.93               0.0696                      181.59
             M.2.7                  ψ(Burn + Water + Village)P(Habitat)                    9                                 4.54               0.0311                      180.02
             M.2.8                  ψ(Village + Burn)P(Habitat)                            8                                12.25               0.0007                      190.91
             
              ΔAICc is the difference between each model’s AICc and the AICc of the top-ranking model.
             
              L is the maximum log-likelihood.

             FIG. 3 Estimated relationship between predicted hog deer                              FIG. 4 Number of sampling sites needed to detect a change in
             occupancy and distance to water. The vertical lines represent                         occupancy rate with varying effect size at a significance level of
             % confidence intervals.                                                             α = ..

             probability of detecting hog deer sign (given presence) was                           % confidence was five. This corresponds to a survey
             highest in burnt grassland (Fig. ).                                                  effort of . hours per grid cell, rather than the -hour
                                                                                                   field surveys conducted. Based on the model-averaged
             Hog deer occupancy No sign of hunting of hog deer using                               occupancy (ĉ = . ± SE .) and detection probability
             firearms was encountered during field surveys. The                                    (P̂ = . ± SE .) estimated from the field data, the
             covariate analysis revealed that species occupancy was                                number of sites that would be required in a future survey
             higher in habitat closer to water (b̂ water = −. ± SE .;                        design to detect a change in occupancy varied considerably
             M.; Table , Fig. ). There was also an effect from human                           under different scenarios (Fig. ). These results revealed the
             activities, with a higher hog deer occupancy in recently burnt                        study area supporting a maximum of  sites and surveyed
             sites (b̂ burnt = . ± SE .) and sites further from villages                     over five occasions would not be able to detect changes in
             (b̂ village = . ± SE .). The summed model weights for                           occupancy of ,  or % with a power of .. At least ,
             each factor with respect to hog deer occupancy were as                                 and  sites would need to be sampled to detect changes
             follows: distance to water (.%), recent burning (.%)                            in occupancy of ,  or %, respectively, with a power
             and distance to village (.%). The model averaged                                   of . ..
             occupancy ĉ was . ± SE ..

                                                                                                   Discussion
             Power analysis According to the estimated mean
             detection probability (P̂ = . ± SE .) the number of                             Several deer species have undergone an overall decline
             replicates (-minute survey intervals) required to                                   across their mainland South-east Asian range, most notably
             determine hog deer presence at an occupied site with                                  sambar, hog deer and Eld’s deer Rucervus eldii (Gray et al.,

                                                                                        Oryx, 2018, 52(1), 126–133 © 2016 Fauna & Flora International doi:10.1017/S0030605316000727
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Hog deer conservation in Myanmar                     131

           ; Timmins et al., a,b). Yet our findings indicate that                        Hog deer occupancy
           the hog deer in our Myanmar study area have not followed
           this trend. The sampling protocol developed and its success-                          The widespread occurrence of the hog deer in our study area
           ful implementation proved to be robust. More importantly,                             raises several points for consideration. Firstly, without a
           our study shed light on a previously little known hog deer                            historical baseline from the wider Indawgyi landscape we
           population in Myanmar by revealing a high occupancy                                   cannot fully rule out that the current population is in fact
           across its putative habitat, and this information was used                            a remant of one that once extended across a larger range,
           to influence conservation planning directly. This is welcome                          and is therefore declining. We recommend expanding fu-
           news for a species that is under immense pressure. Security                           ture surveys beyond the putative range, which was identified
           concerns notwithstanding, we recommend using this rapid                               through preliminary field surveys, including interviews with
           survey technique across the wider Indawgyi landscape and                              the local community. Not only is this predicted to improve
           mapping the status of the hog deer elsewhere in Myanmar,                              statistical rigour in measuring population trends, it would
           especially in areas of tall grassland and riparian forest that                        also reduce the likelihood of individuals being missed and
           may have been overlooked previously.                                                  excluded from subsequent conservation planning. There is
                                                                                                 a seemingly suitable grassland habitat by the west side of
                                                                                                 Indawgyi Lake but it was not possible to survey there be-
                                                                                                 cause of security concerns.
           Sampling protocol                                                                         In the Indawgyi landscape hog deer occupancy was high-
           In tropical Asia the applicability of occupancy survey tech-                          er in habitat that was closer to water. This finding fits with
           niques for conducting range-wide assessments has been de-                             the species’ known preference for tall grassland and riparian
           monstrated for entire species (Asian tapir Tapirus indicus),                          forest, which is associated with the floodplains of large rivers
           subspecies (Sumatran tiger Panthera tigris sumatrae) and                              and lakes (Odden et al., ). Monsoonal flooding, as well
           populations (sun bear Helarctos malayanus, which was ca-                              as anthropogenic burning of grass (for which we found a
           tegorized as Data Deficient at the time; Linkie et al., ,                         positive and significant correlation with hog deer occu-
           ; Wibisono et al., ). Our application of this technique                       pancy), would stimulate the growth of young and edible
           to the hog deer yielded precise estimates of occupancy and                            shoots, thereby increasing food availability for hog deer, as
           detection probability. Furthermore, the sampling protocol                             found for the chital Axis axis (Moe & Wegge, ).
           required minimal training for a team with no prior experi-                            Although the results suggest that burning was not detrimen-
           ence of conducting surveys within a capture–recapture                                 tal to the hog deer (e.g. through reducing hiding cover), the
           framework, although training in identification of species                             species did exhibit a tendency to avoid villages. This may
           sign, especially where sympatric species occur, may be chal-                          have been to evade a threat not quantified in this study,
           lenging for an inexperienced team. The baseline results are                           such as areas of higher human activity in Pakistan that
           promising, and the power analysis identified where the                                were completely avoided by hog deer (Arshad et al., ).
           protocol should be refined.
               A simple modification to increase confidence in confirm-                          Threats to the hog deer
           ing the presence of hog deer would be to increase the survey
           effort from  to . hours per grid cell. A more challenging                          Hog deer may have thrived in the Indawgyi landscape be-
           modification would be to increase the number of survey                                cause of lower levels of threats that have been identified as
           sites, to detect a significant change in population trend.                            being important elsewhere, primarily the conversion of
           Based on the current sampling framework and its results,                              floodplain grassland to rice paddy, attacks by domestic
           a change in occupancy would only be detected if it were at                            dogs, the use of poisons to protect crops from wild herbi-
           least ± %. To improve the detection level would require                             vores, and hunting for wild meat using snares and guns.
           increasing the number of sampling sites beyond the current                            Other threats were absent; for example, competition from
           range maximum of  cells. This finding has important im-                             livestock grazing, competition with other wildlife (e.g. ele-
           plications for similar studies in tropical landscapes where                           phant, sambar, gaur Bos gaurus) for grazing, and the pres-
           the extent of habitat left to monitor is small, especially re-                        ence of large felid predators, such as the tiger and leopard
           garding the need to understand the occupancy dynamics                                 Panthera pardus (Bhowmik, ). Furthermore, informal
           of colonization and extinction within grid cells. As a caveat,                        interviews with two local hunters revealed that home-made
           grid cell size may need to vary based on varying habitat                              guns were typically used in the past to shoot hog deer, and
           quality across the hog deer’s range to ensure that occupancy                          also spears or knives, particularly at night in paddy fields
           is being measured, and where hog deer live in extensively                             during the rainy season, when it is easier to creep up
           flooded landscapes rapid surveys should be conducted in                               close. However, these interviews also revealed that hog
           both wet and dry seasons to avoid possible sampling biases                            deer hunting was considered to be minimal both in the
           associated with seasonal movements.                                                   past and at present. Nonetheless, during a routine project

           Oryx, 2018, 52(1), 126–133 © 2016 Fauna & Flora International doi:10.1017/S0030605316000727
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. https://doi.org/10.1017/S0030605316000727
132         N. Lwin et al.

             site visit in  the survey team found a hunting platform in                        significant habitat conversion). However, our sampling proto-
             the grassland, and the occupancy team would have found it                             col could be extended to include other little-known deer spe-
             difficult to detect signs of hunting with guns during surveys.                        cies, such as sambar and Eld’s deer, in South-east Asia.
             It is difficult to quantify the threat posed by hunting, and we
             recommend a fuller assessment; however, the widepsread
             occupancy of hog deer recorded suggests that the level of                             Acknowledgements
             threat is not high in our study area.
                 The absence of a covariate for the presence of dogs, as a                         We thank Patrick Oswald for GIS support, Sarah Brook for
             proxy for hunting, may be a limitation in our study. We used                          sharing information on the hog deer, the Myanmar Forestry
             distance to village as a proxy for human disturbance (a com-                          Department for survey permission, and the Conservation
             monly used technique in hunting and deforestation studies                             Leadership Programme and the Helmsley Charitable Fund
             in the tropics) and this should have partly controlled for the                        for funding the work.
             presence of dogs, if indeed they had an effect. Thus, whereas
             we cannot directly disprove the relationship between hog
             deer and the presence of dogs, the widespread hog deer oc-                            Author contributions
             cupancy (% of the study area) suggests that hunting was                             ML, NL and FM conceived and designed the study. NL, SSA
             not influential. If dogs were critically important and hunting                        and AKL conducted the fieldwork. AH analysed the data.
             was high then the widespread occupancy pattern we re-                                 ML, NL, AH and FM wrote the article.
             corded for this threatened species would not have been
             found. The major threat to the hog deer population is
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           Oryx, 2018, 52(1), 126–133 © 2016 Fauna & Flora International doi:10.1017/S0030605316000727
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. https://doi.org/10.1017/S0030605316000727
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