896 J. Rode-Margono et al. Social behaviour and reproduction


Mean group and litter sizes, and numbers of adults, are in Table 3. Sample sizes for Bawean deer were too low to inves- tigate reproductive patterns, with immature individuals re- corded only in April and August (Fig. 4a). Bawean warty pigs were recorded in small family groups (with or without males), pairs, and as single males. Changes in group struc- ture over the year indicate a reproductive peak in the dry season, particularly in August (Fig. 4b).


Discussion


FIG. 2 Predicted occupancy (mean ± SD) of Bawean warty pigs in relation to distance to nearest village.


We obtained only two captures of deer over the first 3


months of our study (November 2014–January 2015), from 102 fully random trap positions. In the following 6 months (February–July) we sampled an additional 31 random loca- tions (47 ± SD 19 days/location), resulting in six more cap- tures of deer. The inclusion of five preferentially positioned traps during August–October (80 days/location) resulted in 30 additional captures, 27 (90%) of which were from a single location. These records were insufficient to calculate a popu- lation estimate for the Bawean deer using randomencounter modelling.


Activity patterns


Captures of Bawean deer (n = 56) indicated an overall activ- ity level of 0.56, but Rayleigh tests did not detect significant deviation from a uniform daily activity distribution (z = 1.22, P=0.295), suggesting this species may be cathemeral (Fig. 3a). Nevertheless, deer tended to be more active at dusk than dawn (P = 0.012) or midday (P,0.01), with a mean activity time of 20.36 ± circular SD 7 minutes. Records of Bawean warty pigs (n = 1,749) indicated an over- all activity level of 0.52, with Rayleigh tests showing an uneven distribution of daily activity (z = 19.13,P,0.01; Fig. 3b). Pigs weremost active at dawn (P,0.01 for all pair- wise comparisons; mean activity time was 03.22 ± circular SD 7 minutes), with a second peak at dusk (P,0.01), and were least active at midday (P,0.01;Wald tests), indicating a tendency for crepuscular activity patterns. There was no significant difference in number of encounters between day and night for either species (warty pig: χ2 = 2.438,df = 1, P=0.119; deer: χ2 = 1.6842,df= 1,P= 0.194). However, given the limited number of records of the Bawean deer, the observed activity patterns for this species need to be interpreted cautiously.


Relative abundance, distribution and habitat preferences Our results indicate that occupancy of Bawean warty pigs is negatively correlated with distance to villages but not with other measured covariates, such as tree height, density and diameter, habitat type, or distances to roads and protected area borders. In contrast, Rademaker et al. (2016)found a negative correlation between camera-trap rate and distance to protected area border, as well as a preference for commu- nity forest. Our occupancy model may have been unable to detect influences of habitat type because the majority of cam- eras were located in two habitat types: tall forest (60%) and rice cultivation (15%). However, Bawean warty pigs have pre- viously been found to prefer semi-open cultivated habitat (Semiadi & Meijaard, 2006; Meijaard, 2014), and this may have been captured in our data by the higher probability of occupancywith closer proximity to villages. Froma conserva- tion perspective this preference poses a risk to the pigs, as crop damage on Bawean Island is mainly combatted by hunting (Rode-Margono et al., 2016b;Rahman etal., 2017a); the use of non-specific hunting methods (e.g. snares) and associated stress may also affect Bawean deer (BBKSDAEast Java, 2009). Captures of Bawean deer were restricted to two areas,


with the majority of videos originating from a single loca- tion. Rahman et al. (2017a) detected high abundance in the same area and presence in a third location, using camera traps, and identified a low number of faecal samples in a fourth location. They did not detect deer in the area where the other 8% of our videos were recorded. Rahman et al. (2017b) suggested that Bawean deer prefer


secondary forest over primary forest, possibly because of higher productivity. Furthermore, they reported that Bawean deer use forests as refuges and edge habitat for for- aging,which puts themat risk of conflictwith people and pre- dation by feral hunting dogs. Although we could not analyse habitat preference because of insufficient data, the distribu- tion of our records confirmsthe deer’s occurrence in commu- nity forests and tall forests near forest edges, but not in the interior of the island, which is presumably primary forest. The apparent absolute avoidance of some parts of the


Oryx, 2020, 54(6), 892–900 © 2019 Fauna & Flora International doi:10.1017/S0030605318000996


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84  |  Page 85  |  Page 86  |  Page 87  |  Page 88  |  Page 89  |  Page 90  |  Page 91  |  Page 92  |  Page 93  |  Page 94  |  Page 95  |  Page 96  |  Page 97  |  Page 98  |  Page 99  |  Page 100  |  Page 101  |  Page 102  |  Page 103  |  Page 104  |  Page 105  |  Page 106  |  Page 107  |  Page 108  |  Page 109  |  Page 110  |  Page 111  |  Page 112  |  Page 113  |  Page 114  |  Page 115  |  Page 116  |  Page 117  |  Page 118  |  Page 119  |  Page 120  |  Page 121  |  Page 122  |  Page 123  |  Page 124  |  Page 125  |  Page 126  |  Page 127  |  Page 128  |  Page 129  |  Page 130  |  Page 131  |  Page 132  |  Page 133  |  Page 134  |  Page 135  |  Page 136  |  Page 137  |  Page 138  |  Page 139  |  Page 140  |  Page 141  |  Page 142  |  Page 143  |  Page 144  |  Page 145  |  Page 146  |  Page 147  |  Page 148  |  Page 149  |  Page 150  |  Page 151  |  Page 152  |  Page 153  |  Page 154  |  Page 155  |  Page 156  |  Page 157  |  Page 158  |  Page 159  |  Page 160  |  Page 161  |  Page 162  |  Page 163  |  Page 164