Sign and habitat impact of banteng (Bos javanicus) and pig (Sus scrofa), Cobourg Peninsula,northern Australia

The habitat preference and impact of banteng (Bos javanicus) and pigs (Sus scrofa) in Gurig National Park, on Cobourg Peninsula, Northern Territory, was investigated by systematically sampling twelve habitats. Animal signs (banteng and pig scats) and impacts (area of rooted, trampled or pugged ground and number of rubbed tree trunks) were recorded in 696 quadrats, each 5 × 20 m. Significant differences among habitats in sign and impact were detected. Pig rooting was concentrated on wetland communities, particularly sedgelands. Banteng sign focused on monsoon forest and coastal plains, where they caused less obvious damage than pigs. There was little evidence of either ungulate in the eucalypt communities, which are the most widespread of all habitats on the peninsula. In monsoon forests, banteng densities were approximately 70 per km^-2, Banteng, unlike pigs and buffalo, have remained near their point of introduction over the last 140 years, possibly because of the unique habitat mosaic consisting of grasslands abutting monsoon forest.     

Clidemia hirta Invasion at the Pasoh Forest Reserve: An Unexpected Plant Invasion in an Undisturbed Tropical Forest1

Clidemia hirta is a highly invasive shrub in tropical forests throughout the world, but has had little success invading mainland sites and undisturbed forests. In the early 1990s, this plant was found to have invaded an unexpected site, an undisturbed continental tropical forest at Pasoh, Peninsular Malaysia. In 1997, a study was conducted of the C. hirta population at the Pasoh Forest Reserve. A demographic survey of the 50–ha long–term research plot at Pasoh located 1002 C. hirta individuals, 69 of which were reproductive at the time of the study. All but 8 individuals were located in high light gaps or gap edges. Relative growth rates were significantly higher in gaps and gap edges than in the understory, and no reproductive individuals were found in the understory. Mean plant size and dry biomass density increased steadily over the course of the study, while the observed mortality rate was 0 percent over two months. The biomass density of Clidemia at Pasoh was <500 g/ha at the conclusion of this study, but because the population is confined almost exclusively to high light environments, its density in these sites is much higher. The location of C. hirta plants in gaps was significantly correlated with past disturbance by wild pigs, suggesting that soil disturbance and light availability are essential for their establishment. The implication of this study is that by competing with native species in gaps, C. hirta invasion has the potential to alter forest regeneration at Pasoh. Changing land use practices near the reserve have increased the number of wild pigs, and thus the level of disturbance, which may explain the recent success of C. hirta at Pasoh.     

Outreach increases detections of an invasive species in a crowdsourced monitoring program

Crowdsourcing can be a useful tool for the early detection of invasive species. Invasive wild pigs (Sus scrofa) have been reported in Ontario, Canada. We compared trends in reporting frequency of wild pig sightings to trends in media events that included directions for the public on where to submit their wild pig sightings. We found that media events occurring on the same week, and in up to two weeks before the sighting was reported significantly increased the number of wild pig reports we received. Our findings suggest that media can be used to increase participation by the public. Because of this relationship, our findings also imply that reporting frequency alone cannot accurately index real changes in wild pig numbers—participants were more likely to report sightings after they had been exposed to relevant media, and spikes in the number of reports tracked our outreach efforts. Despite this limitation, reports of wild pig sightings from community members remain a cost-effective tool to detect low-density invasive species across large regions, and participation in the program can be increased with periodic news media and social media blitzes.

     

Predicting home range size from the body mass or population densities of feral pigs,Sus scrofa (Artiodactyla: Suidae)

Telemetry studies of feral pigs (Sus scrofa, L.) in different habitats were used to predict home range size, from (i) body mass and (ii) population density. Geometric mean regressions of the log_e transformed data indicated that body mass of male and female feral pigs and mean population density were good predictors of the home range size of feral pigs (r² = 0.81, 0.77 and 0.85 respectively). There were no sexual differences in home range size of feral pigs once the effect of body mass was taken into account. Use of these variables in models that incorporate spatial aspects along with the practical application of the results to the management of feral pig populations are briefly discussed.     

北京地区同域分布的普通和黑头种群密度比较

2007年4月至7月,2007年12月至2008年1月,分别在北京市门头沟区小龙门森林公园、百花山自然保护区以及延庆县松山自然保护区,对同域分布的普通(Sitta europaea)和黑头(Sitta villosa)两种同域分布的类种群密度进行了调查。普通在小龙门森林公园、百花山自然保护区和松山自然保护区的种群密度分别是40.92、96.67只/km2和16.67只/km2。而黑头在上述3个调查区域的种群密度分别是2.03、16.67只/km2和23.33只/km2。普通的总体平均密度(51.4只/km2)高于黑头(20.68只/km2)。两种类分布的海拔和林型存在着差异。普通在海拔高度1070—1350 m的分布比较多。在海拔段1070—1250 m区间,普通的数量随海拔高度的增加呈递增的趋势。而黑头在海拔600—800 m分布较多,随着海拔高度的增加,种群数量呈递减趋势。普通主要分布在阔叶林和针阔混交林中,而黑头主要分布在针叶林中。     

Eradication of Feral Pigs From Pinnacles National Monument

Abstract: Feral pigs (Sus scrofa) have caused considerable damage where they have been introduced around the world. At Pinnacles National Monument, California, USA, managers were concerned that feral pigs were damaging wetland habitats, reducing oak regeneration, competing with native wildlife, and dispersing nonnative plant species through soil disturbance. To address these threats the National Park Service constructed an exclosure around 57 km² of monument land and through cooperation with the Institute for Wildlife Studies eradicated all feral pigs within the area. Trapping, ground-hunting, hunting dogs, and Judas techniques were used to remove feral pigs. Trapping techniques removed most pigs, but a combination of techniques was required to cause eradication. A series of bait sites and transects across the monument helped focus removal efforts and facilitated detection of the last remaining feral pigs in the exclosure. Consistent funding and cooperation from the National Park Service allowed for a seamless and comprehensive program that provided intensive removal of feral pigs. The successful eradication of feral pigs at Pinnacles National Monument should encourage managers in other areas to implement future control or eradication programs.     

Population densities of Sulawesi crested black macaques (Macaca nigra) on Bacan and Sulawesi,Indonesia: Effects of habitat disturbance and hunting

Population surveys of Sulawesi crested black macaques (Macaca nigra) were conducted on the Indonesian islands of Sulawesi and Bacan in 1992–1994 to assess the status of natural populations and determine habitat and anthropogenic factors affecting their population densities. We surveyed five sites for primates, including undisturbed and disturbed habitats. Data were collected on habitat structure and composition at two undisturbed and one disturbed forest site in which the primates were surveyed. The highest density of macaques was found in primary forest at Gunung Sibela Nature Reserve on Bacan (170.3 individuals/km²). Population density in logged forest on Bacan was high but significantly less than primary forest (133.4 individuals/km²). The high density of crested black macaques in primary forest on Bacan is best explained by the high carrying capacity found in primary forest. The lower food quantity and quality of food resources found in logged forest correlated with lower primate densities compared to primary forest. However, the large population of macaques in logged forest demonstrates the conservation value of such forest. Densities on Sulawesi at Tangkoko-Batuangas-DuaSudara Nature Reserve (TBDS) showed a continuing decline since earlier surveys. Primate densities were highest near the protected center of Tangkoko Reserve (66.7 individuals/km²). The peripheral areas of Batuangas and DuaSudara, even though adjacent and continuous, showed lower population densities of 46.4 and 23.5 individuals/km², respectively. The best explanation for the continued decline of Macaca nigra populations at TBDS is hunting. Unless conservation measures are implemented immediately, M. nigra on Sulawesi risks extinction in the near future. Am. J. Primatol. 44:89–106, 1998. © 1998 Wiley-Liss, Inc.     

Prehistoric Introduction of Domestic Pigs onto the Okinawa Islands: Ancient Mitochondrial DNA Evidence

Ancient DNAs of Sus scrofa specimens excavated from archaeological sites on the Okinawa islands were examined to clarify the genetic relationships among prehistoric Sus scrofa, modern wild boars and domestic pigs inhabiting the Ryukyu archipelago, the Japanese islands, and the Asian continent. We extracted remain DNA from 161 bone specimens excavated from 12 archaeological sites on the Okinawa islands and successfully amplified mitochondrial DNA control region fragments from 33 of 161 specimens. Pairwise difference between prehistoric and modern S. scrofa nucleotide sequences showed that haplotypes of the East Asian domestic pig lineage were found from archaeological specimens together with Ryukyu wild boars native to the Ryukyu archipelago. Phylogenetic analysis of 14 ancient sequences (11 haplotypes; 574 bp) indicated that S. scrofa specimens from two Yayoi-Heian sites (Kitahara and Ara shellmiddens) and two Recent Times sites (Wakuta Kiln and Kiyuna sites) are grouped with modern East Asian domestic pigs. Sus scrofa specimens from Shimizu shellmidden (Yayoi-Heian Period) were very closely related to modern Sus scrofa riukiuanus but had a unique nucleotide insertion, indicating that the population is genetically distinct from the lineage of modern Ryukyu wild boars. This genetic evidence suggests that domestic pigs from the Asian continent were introduced to the Okinawa islands in the early Yayoi-Heian period (1700–2000 BP), or earlier.     

Influence of Forest Fragmentation on the Winter Abundance of Mammals in Mt. Chirisan National Park,South Korea

Abstract: We examined the influence of both local habitat and landscape variables on mammal species abundance in a forest fragmented by road construction and in continuous forest in 8 study sites in Mt. Chirisan National Park, South Korea, from 2001 to 2004. We recorded tracks of 8 species of mammals, Siberian weasels (Mustela sibirica), yellow-throated martens (Martes flavigula), Bengal cats (Felis bengalensis), wild boars (Sus scrofa), water deer (Hydropotes inermis), roe deer (Capreolus capreolus), Korean hares (Lepus coreanus), and red squirrels (Sciurus vulgaris), on the snow on 8 2-km transects in our study areas. There were significant differences in density of snags, mean tree basal area, and in shrub coverage between the fragmented and unfragmented forest areas. We found significant differences in abundance index of tracks between the fragmented and unfragmented areas for 5 mammal species; the others had even distributions. Of the 8 mammal species analyzed, 5 species related to landscape and local vegetation variables in a stepwise approach with repeated measures. Landscape variables are significant predictors of abundance for many mammal species. Forest managers should consider multiple measures of forest fragmentation sensitivity when making forest management decisions.     

Opportunistic Predation of Wild Turkey Nests by Wild Pigs

Wild pigs (Sus scrofa; i.e., feral hogs, feral swine) are considered an invasive species in the United States. Where they occur, they damage agricultural crops and wildlife habitat. Wild pigs also depredate native wildlife, particularly ground-nesting bird species during nesting season. In areas inhabited by wild turkeys (Meleagris gallopavo), nest destruction caused by wild pigs may affect recruitment. There is debate whether wild pigs actively seek ground-nesting bird nests or depredate them opportunistically. To address this debate, in 2016 we examined the movements of wild pigs relative to artificial wild turkey nests (i.e., control [no artificial nests], moderate density [12.5–25 nests/km²], and high density [25–50 nests/km²]) throughout the nesting season (i.e., early, peak, and late) in south-central Texas, USA. We found no evidence that wild pigs learned to seek and depredate wild turkey nests relative to nest density or nesting periods. Despite wild pigs being important nest predators, depredation was not a functional response to a pulsed food resource and can only be associated with overlapping densities of wild pigs and nests. Protecting reproductive success of wild turkeys will require reducing wild pig densities in nesting habitat prior to nesting season. © 2019 The Wildlife Society.     

Density,habitat use,and daily activity patterns of the Red-rumped Agouti (Dasyprocta leporina) in the Atlantic Forest,Brazil

The Red-rumped Agouti (Dasyprocta leporina, Linnaeus, 1758) is considered common in areas where it occurs, and it is listed as Least Concern status in the IUCN red list; however, in recent decades it has been negatively affected by habitat loss and hunting. The conservation status needs to be updated since no recent studies have been conducted in the Atlantic Forest. Therefore, we aimed to estimate the density, occupancy and detectability of D. leporina in one of the larger Atlantic Forest remnants in Espírito Santo, Brazil, the Vale Natural Reserve (VNR). We surveyed four line transects between April 2013 and May 2014 to estimate density and abundance. To model occupancy probability, as well as to document activity pattern, we selected 39 sampling sites with one camera-trap each. Estimated density was 21 ± 3 individuals km^–2 and estimated population size was 4935 ± 368 individuals. Occupancy increases with palm density, distance from forest edge, and canopy cover. Occupancy and detectability decreases with distance from water resources. Detectability increases with palm density. The results presented herein can be a starting point to support future action plans for the species, making predictions regarding the ecosystem and management and conservation of D. leporina.     

Census and distribution of the golden lion tamarin (Leontopithecus rosalia)

During 1990–1992, a survey of the golden lion tamarin, Leontopithecus rosalia, was carried out throughout its known distribution area. Forest remnants were identified by visual interpretation of Landsat‐TM satellite images. Localities occupied by L. rosalia were first identified by interviews with local people. All forests more than 20 ha in size, and for which two or more interviews suggested the presence of the species, were surveyed using “play‐back” recordings of lion tamarin long calls. The total wild population of L. rosalia, including that of the Poço das Antas Biological Reserve, was estimated to be 562 individuals in 109 groups. The lion tamarins were generally found in four major areas of forest (six or more groups per forest, not including Poço das Antas), with a further 12 groups isolated in small forest patches. Currently the species' distribution is restricted to just four municipalities in the state of Rio de Janeiro: Silva Jardim, Cabo Frio, Saquarema, and Araruama. Although they are typically confined to lowland forest of <300 m altitude, L. rosalia was recorded at an altitude of 550 m in one locality. Average group size varied from 3.6 to 5.7 individuals, and densities from 0.39 groups/km² to 2.35 groups/km² (2.17 individuals/ km² to 8.53 individuals/km²). Six of the isolated groups found during the survey were successfully translocated to a forest of 2,400 ha. There is now also a significant population of reintroduced lion tamarins. Overall, however, the possibilities for further expansion of the wild population are severely limited. Am. J. Primatol. 59:29–44, 2003. © 2003 Wiley‐Liss, Inc.     

尼日利亚西南部森林区域中大猩猩的状况调查

我们利用标准化调查和广泛调查两种方法对尼日利亚西南部森林中黑猩猩(Pan troglodytes)的分布状态进行了调查。本研究确认该地区总计2 443·58 km2的15个森林保护区内存在该物种。然而基于间接证据,该地区之前仅有8个森林保护区共计1 920·48 km2被调查过。我们将独立收集的年度数据根据不同保护区进行分类总结并且估计了建巢黑猩猩的个体密度。研究结果显示该地区的黑猩猩呈低密度高分散分布,其中只有Eba和Ise两个森林保护区中黑猩猩的分布密度显著大于0·20/km2。研究区域内四个森林保护区中黑猩猩的建巢数大于10 (Akure/Ofosu森林保护区,13个; Oluwa森林保护区, 11个;Ise森林保护区22个; Ago-Owu森林保护区,11个)。此外,在Ise森林保护区内我们观察到黑猩猩其它活动(例如观望行为,发声行为,取食迹象和粪便)的频次显著高于其它森林保护区。研究结果表明,残余且易于管理的黑猩猩种群分布于该调查区域。建议采取适当的保护措施来保证它们的继续生存     

Density Estimation of the Endangered Udzungwa Red Colobus (Procolobus gordonorum) and Other Arboreal Primates in the Udzungwa Mountains Using Systematic Distance Sampling

Estimates of population density and abundance are essential for the assessment of nonhuman primate conservation status, especially in view of increasing threats. We undertook the most extensive systematic primate survey yet of the Udzungwa Mountains of Tanzania, an outstanding region for primate endemism and conservation in Africa. We used distance sampling to survey three arboreal monkey species, including the endangered and endemic Udzungwa red colobus (Procolobus gordonorum). Overall, we encountered 306 primate clusters over 287 km walked along 162 line transects. We found the lowest cluster densities for both red colobus and Angolan colobus (Colobus angolensis; 0.8 clusters/km²) in the least protected forest (Uzungwa Scarp Forest Reserve, US), while we found the highest densities (3.2 and 2.6 clusters/km² for red colobus; 3.2 and 2.7 clusters/km²for Angolan colobus) in two large and protected forests in the national park. Unexpectedly, Magombera, a small forest surrounded by plantations, had the highest densities of red colobus (5.0 clusters/km²), most likely a saturation effect due to the rapid shrinking of the forest. In contrast, Sykes’ monkey (Cercopithecus mitis monoides/moloneyi) had more similar densities across forests (3.1–6.6 clusters/km²), including US, suggesting greater resilience to disturbance in this species. For the endemic red colobus monkey, we estimated an abundance of 45–50,000 individuals across all forests, representing ca. 80% of the global population. Though this is a relatively high abundance, the increasing threats in some of the Udzungwa forests are of continued concern for the long-term survival of red colobus and other primates in the area.     

Feral pig population structuring in the rangelands of eastern Australia: applications for designing adaptive management units

Feral pigs (Sus scrofa) are an invasive species in Australia. Their negative impact on conservation values has been demonstrated, and they are controlled in many areas in the rangelands of Australia. However, they are usually controlled over small, often ad hoc management units (MUs), and previous research has revealed that these MUs can be inadequate. Understanding feral pig population structuring can aid in the design of appropriate MUs. This study documents an approach to improving MUs for feral pig control in the rangelands of Australia. Feral pigs from a 500,000 km² region were genotyped with 13 polymorphic markers. Genetic analyses were used to identify population structure. Identified sub-populations were then related to geographical and environmental gradients with geographical information systems, regression analysis and with canonical correspondence analysis. Five sub-populations were identified. These were moderately differentiated, with relatively high-migration rates. Two sub-populations in drier, lower elevation areas overlapped, due to extensive migration, probably along the large, inland rivers and flood plains. Sub-populations in higher rainfall environments appeared less likely to migrate. Sub-population differentiation was also dependant on distance, indicating isolation by distance was present. A case study applying an adaptive MU to a previously controlled area is presented. Generally, however, MUs for feral pig control for natural resource protection and endemic disease eradication in the rangelands should take into account geographical size, but also geographic features, especially major rivers in low-rainfall areas.     

Distribution and abundance of plants with extrafloral nectaries in the woody flora of a lowland primary forest in Malaysia

The first data on the taxonomic distribution and abundance of woody plants with extrafloral nectaries (EFN) from SE Asia are reported. The species richness and frequency of woody angiosperm plants with extrafloral nectaries was studied in the Pasoh Forest Reserve, a primary lowland forest in Peninsular Malaysia. EFN were present on 12.3% of the 741 species surveyed. 91 plant species belonging to 47 genera and 16 families were found to have EFN. Euphorbiaceae, Dipterocarpaceae, Rosaceae, Leguminosae, and Ebenaceae were the families most frequently bearing EFN whereas EFN were rare in the more primitive subclasses of the Magnoliopsida and common in the more advanced taxa (Dilleniidae, Rosidae, Asteridae). Most common were flattened glands associated with the leaf blade. A comparison with data from the Neotropics showed a great similarity in regard to the taxonomic distribution of plants with EFN. EFN-plants occupied 19.3% of the cover of the Pasoh Forest 50 ha plot.Species with EFN were under-represented among shrubs and trees of the understorey. We found an increase in the number of species with EFN as well as in their cover from the understorey to the canopy emergents. EFN were found more often among the abundant species (species with n>500/50 ha). Percentage occurrence and cover of EFN-bearing plants in the 50 ha plot of primary forest was lower than recorded for secondary habitats in tropical areas. At present, in the core zone of the Pasoh Forest Reserve which has been investigated only few species known to indicate disturbance occur. Therefore most of the recorded EFN-species cannot be regarded as secondary forest plants.The interactions between ants and EFN-bearing plants appear to be rather facultative and nonspecific. In Pasoh we found 28 ant species from seven genera visiting EFN. Most of the EFN-associated ants belonged to the subfamily Myrmicinae while Ponerines were rare, a pattern which was also reported for the Neotropics.In cooperation with the Forest Research Institute Malaysia, Kepong, 52109 Kuala Lumpur, Selangor, Malaysia.     

Distribution,population density,and status of sympatric cercopithecids in the Campo-Ma’an area,southwestern cameroon

A study on species composition, distribution, and population density of cercopithecids in the Campo-Ma’an area, Southwestern Cameroon, was undertaken from December 1997 until August 2000. A total of 665.5 km of line transects was used for the census. Thirteen diurnal primate species including five endangered species (Gorilla g. gorilla, Pan troglodytes, Mandrillus sphinx, Colobus satanas, Cercocebus torquatus) were recorded in the Campo Forest, the greatest part of which is a logging concession.Cercopithecus nictitans (1.43 groups/km²),C. cephus (1.13 groups/km²),C. pogonias (0.81 groups/km²), andC. torquatus (0.51 groups/km²) occurred at medium frequencies compared to figures from other Central African study sites. Mandrill densities estimated (0.27 groups/km²) show that the area is very important for the conservation of this rare species. Guenon densities found inside areas with a high level of human activities did not differ significantly from densities estimated in areas with a lower level of human activities.C. torquatus densities were significantly higher in the areas with a low level of human disturbance and encounter rates withLophocebus albigena also indicate a preference of less disturbed areas. Mangabeys are thus likely to be adversely affected by human activities in the area. In the Ma’an Forest, which has not been logged yet, ten species were confirmed. The population densities of two guenons (C. nictitans andC. cephus) were estimated to be twice as high in the unlogged forest area as compared to the logged forest of Campo. Other species are rarer in the Ma’an Forest than in the Campo Forest. Although mangabeys are adversely affected by human activities, the results still indicate that selective logging may be compatible with the conservation of cercopithecids, if a reduced damage logging concept and antipoaching measures are implemented. Increased hunting activities following logging operations will definitely have a negative longterm impact on primate populations in the Campo-Ma’an area if no further, more effective conservation measures will regulate wildlife use in future.     

High density of white-faced capuchins (Cebus capucinus) and habitat quality in the Taboga Forest of Costa Rica

Across the globe, primates are threatened by human activities. This is especially true for species found in tropical dry forests, which remain largely unprotected. Our ability to predict primate abundance in the face of human activity depends on different species' sensitivities as well as on the characteristics of the forest itself. We studied plant and primate distribution and abundance in the Taboga Forest, a 516-ha tropical dry forest surrounded by agricultural fields in northwestern Costa Rica. We found that the density of white-faced capuchins (Cebus capucinus) at Taboga is 2–6 times higher than reported for other long-term white-faced capuchin sites. Using plant transects, we also found relatively high species richness, diversity, and equitability compared with other tropical dry forests. Edge transects (i.e., within 100 m from the forest boundary) differed from interior transects in two ways: (a) tree species associated with dry forest succession were well-established in the edge and (b) canopy cover in the edge was maintained year-round, while the interior forest was deciduous. Sighting rates for capuchins were higher near water sources but did not vary between the edge and interior forest. For comparison, we also found the same to be true for the only other primate in the Taboga Forest, mantled howler monkeys (Alouatta palliata). Year-round access to water might explain why some primate species can flourish even alongside anthropogenic disturbance. Forest fragments like Taboga may support high densities of some species because they provide a mosaic of habitats and key resources that buffer adverse ecological conditions.     

黑龙江省东完达山地区东北虎猎物种群现状及动态趋势

猎物种群丰度是限制虎分布和数量的关键因子,因此猎物种群密度监测和估算是虎保护的重要内容之一。应用采用大样方法,地理信息系统技术和多元统计分析,研究了黑龙江东完达山东部地区东北虎猎物种群(马鹿、狍子和野猪)现状及动态变化趋势。结果表明:研究地区马鹿的种群平均密度为(0.2010±0.0270)只/km²、狍子的平均种群密度为(0.4980±0.0436)只/km²、野猪的平均种群密度为(0.3423±0.0275)只/km²。单因素方差分析表明,在相同生境下,3种有蹄类密度在在阔叶混交林中和杂木林中差异极为显著;不同的生境,3种猎物的猎物的密度也存在着显著差异。相关分析表明马鹿密度和野猪密度程正相关,而马鹿密度和狍子密度、狍子密度和野猪密度则不相关。 同1989年该地区东北虎猎物种群相比:1989-2002年的13 a时间内马鹿的年平均递减率为13.48%、狍子的年平均递减率为12.69%、野猪的年平均递减率为1.89%。     

Recolonizing native wildlife facilitates exotic plant invasion into Singapore's rain forests

Halting biological invasions and rewilding extirpated native fauna are conservation interventions to bolster biodiversity, species interactions, and ecosystems. These actions are often considered separately and the potential for reintroduced wildlife to facilitate invasive plants has been largely overlooked. Here, we investigated the role of Singapore's recolonizing native wild pigs (Sus scrofa) in facilitating an invasive weed Miconia crenata into tropical rainforests, which are normally highly resistant to invasion. We conducted line-transect surveys in 11 Singaporean rain forests and used generalized linear mixed models to consider the contribution of pigs' soil disturbances, human forest paths, and other environmental covariates, on the density of M. crenata. We found that M. crenata was more abundant at forest edges and invasion into forest interior was facilitated by pigs, paths, and canopy gaps, but that these effects were all additive, not synergistic (i.e., not multiplicative). These results highlight how modern invasions are driven by multiple disturbances as well as propagule pressure (e.g., urban birds dispersing seeds at forest edges where they establish in pig soil disturbances). Singapore's extensive native forest restoration efforts may have provided plentiful edge and secondary forests that are well suited to pigs and M. crenata, which in turn undermine the aims of fostering later-successional native plant communities. To prevent negative externalities, we suggest that plant restoration and rewilding projects consider the potential role of wildlife in facilitating non-native plants, and couple these actions with preliminary screening of unintended consequences and continued monitoring, as well as limiting human-mediated weed invasion to minimize propagule sources.