Approximately 60% of this species' distribution is in humid tropical forests. However, white-lipped peccaries are found in a wide diversity of habitats including wet and dry grasslands and woodlands, xerophytic areas like the Gran Chaco, tropical dry forests, and coastal mangroves (Wetzel and Lovett 1974, Mayer and Brandt 1982, Vaughan 1983, Sowls 1984, Altrichter and Boaglio 2004, Taber et al. 2008, Desbiez et al. 2009b). White-lipped peccaries tend to frequent areas close to water and may even visit coastal beaches to forage. In forest areas, they avoid open habitats such as savannas, and preferentially use forest corridors (Richard-Hansen et al. 2019, Jorge 2021). Peccaries are primarily frugivorous, but will eat other plant resources, invertebrates, fungi, and even occasional fish (Husson 1978, Kiltie 1981, Bodmer 1989, Fragoso 1994, Beck 2005, Desbiez et al. 2009a, Keuroghlian and Eaton 2008a, Fernandes et al. 2013). Beck (2006) determined that white-lipped peccaries fed on 144 plant species belonging to 36 families across their range. In some areas of the Brazilian Cerrado where forest reserves are surrounded by corn plantations, they will also feed on corn and soybeans (Jacomo 2002, Jacomo et al. 2013, Painkow et al. 2024). The species plays an important role as prey for large felines, ecosystem engineers, and in the function and structure of Neotropical forests as a major predator and disperser of seeds (Bodmer 1991, Painter 1998, Altrichter et al. 1999, Beck 2005, Keuroghlian and Eaton 2008a, Desbiez 2009a, Desbiez and Keuroghlian 2009, Keuroghlian et al. 2009, Cavalcanti and Geese 2010, Beck et al. 2010).

A number of radiotelemetry-based home range size estimates are now available from a diversity of habitats across this species' distribution. White-lipped peccaries travel long distances, and long-term studies evaluating their home range indicate non-random seasonal movements (Fragoso 1994, 1998a; Keuroghlian et al. 2004, 2015; Keuroghlian and Eaton 2008; Jorge et al. 2019) or non-random but multiannual movements (Reyna-Hurtado et al. 2009). They may also move long-distances of 10-100 km or more during population dispersal (Fragoso 2004, Fragoso et al. 2022). The main environmental factors that determine the movement and home range of the species are food availability, habitat and resource diversity, vegetation cover, and water sources (Altrichter et al. 2001; Keuroghlian and Eaton 2008; Reyna-Hurtado et al. 2009, 2012; Camino 2016; Beck et al. 2017; Jorge et al. 2019). They are diurnal, typically more active early in the morning and late in the afternoon (Mayer and Wetzel 1987, Galleti et al. 2015), but they may forage and feed at night during full moon periods (Mendes-Pontes 2004).

In Costa Rica, herds in tropical moist forest were found to have a mean annual home range size of 32-37.8 km² (100% Minimum Convex Polygon, MCP) (Carrillo et al. 2002). Fragoso (1998a, 2004) estimated home ranges from 21.8 to 200 km² (100% MCP) for groups monitored over three years in moist forest of Maraca Island in Roraima state, Brazil. Keuroghlian et al. (2004) estimated an annual herd home range of 29.51 km² (100% MCP) in a fragmented semideciduous Atlantic Forest in southern Brazil. Reyna-Hurtado et al. (2009b) found annual herd home ranges from 43.60 km² to 121.00 km² (100% MCP) in tropical semi-dry forest in the Calakmul Biosphere Reserve in Southern Mexico. Meyer et al. (2019) found herds White-lipped Peccaryto move from 27 to 51 km² in the Darien forests of Panama, while Richard-Hansen et al., (2019) found movements of two herds between 40 to 70 km². The largest home ranges of up to 253 km² have been observed in the Cerrado of Brazil (Jacomo 2004, Painkow-Neto 2024). All home range estimates presented are based on 100% or 95% minimum convex polygons for comparative purposes. Reyna-Hurtado et al. (2009), Carrillo et al. (2002), and Keuroghlian et al. (2004) observed a high level of spatial overlap between sub-herds, and the amount of overlap could vary depending on the season and resources available. In the Pantanal highlands, Jorge et al. (2019) demonstrated that area usage is related to fruit availability. The greater diversity and abundance of fruits during the rainy season led to increased area usage in the region, driven by changes in the spatiotemporal distribution of native fruits. The consensus is that white-lipped peccaries are clearly wide-ranging and require large areas for survival (Altrichter and Almeida 2002, Keuroghlian et al. 2004, Reyna-Hurtado et al. 2009). Their movements respond in part to changes in the availability of fruit patches and water sources (Mendez 1970; Kiltie and Terborgh 1983; Sowls 1984; Bodmer 1990; Altrichter et al. 2001; Keuroghlian et al. 2004; Beck 2005; Keuroghlian and Eaton 2008a, 2008b, 2009b; Reyna-Hurtado et al. 2009b; Camino 2016).

Tayassuids, particularly white-lipped peccaries, are important ecosystem engineers. By disturbing the soil during foraging, they modify the understory and create water-rich environments. They also alter litter patterns and the composition of vegetation, which significantly impact other species (Silman et al. 2003, Keuroghlian and Eaton 2009). Frequently used sites, wallows, may experience soil compaction, enhancing water retention compared to natural puddles (Beck et al. 2010). Mud wallows, especially those frequented by large herds of white-lipped peccaries, are generally larger (~60 m²) than those used by smaller herds of collared peccaries (~10 m²). As a result, these wallows provide vital habitats for breeding and foraging for various anuran species, particularly during the dry season.

White-lipped Peccary herds often exceed 100 individuals, though groups of as few as five to more than 200 individuals have also been observed (Kiltie and Terborgh 1983, Desbiez 2007, Donkin, 1985, Mayer and Brandt, 1987, Fragoso 2004, Reyna-Hurtado et al. 2009). Reyna-Hurtado et al. (2016) found that large groups exist in areas with more water and far away from human villages. In certain seasons and some areas, large herds divide into smaller groups according to the distribution and abundance of food, although the more frequent reporting of smaller groups in some areas is probably correlated with increased hunting pressure (Ditt 2002). Group sizes in hunted areas adjacent to the Calakmul Biosphere Reserve in Mexico were smaller (Median = 16, SE = 1.84, n = 15) than those living inside the reserve, where no hunting is allowed (Median = 25, SE = 1.84 n = 9, Reyna-Hurtado 2009a). Keuroghlian et al. (2004) observed that a population of 150 white-lipped peccaries in a fragmented area of the Atlantic Forest periodically divided into 3-4 sub-herds with an average of 42 individuals each. They also observed a high frequency of switching of individuals among sub-herds and documented periodic sub-herd fusion and fission. Switching of individuals has also been observed in a long-term (10 years) radiotelemetry study in the Pantanal of Brazil (Keuroghlian 2003; Keuroghlian et al. 2004, 2015) and in Costa Rica (Sáenz and Carrillo 1999). Biondo et al. 2011 analysed two different populations 80 km apart in the Pantanal. They found a low degree of genetic differentiation between the locations analysed, and dispersal by both sexes (contrary to the predicted male-biased dispersal of most mammalian species). In addition, 30% of males and females were predicted to be dispersers, which can indicate high levels of gene flow between the two different herds. For this reason, the researchers stress the need for very large areas to maintain gene flow and genetic diversity between these distant but connected populations and suggest managing them as a unique population; this requires maintaining ecological corridors and natural links between herd populations (Biondo et al. 2011).

In the Gran Chaco, white-lipped peccaries appear to be widely distributed across different habitats and ecotones, despite the presence of both other extant peccary species in this ecoregion. Small to medium-sized groups of white-lipped peccaries have been observed in and around Defensores del Chaco National Park in Paraguay, the country’s largest protected area. These xerophytic forests may be some of the driest habitats occupied by the species; here they appear to occur at low densities but are still frequently taken by jaguars (Giordano 2015). In the humid Paraguayan Chaco of President Hayes Department, they appear to be widely distributed and occur sympatrically with collared peccaries, Chacoan peccaries, and feral pigs (Giordano and Gimenez Baez, unpublished data). In the Palo Santo woodlands, Rio Pilcomayo Basin of Paraguay along the border with Argentina, fairly large herds (minimum of ~70-100 individuals) of white-lipped peccaries have consistently been recorded in the same private reserves for almost 9 years.

The gestation period of the White-lipped Peccary is between 156 and 162 days in zoos (Roots 1966). The average litter size observed in pregnant females captured in the Peruvian Amazon ranged from 1.6 to 1.7 offspring (Gottdenker and Bodmer 1998, Mayor et al. 2009). Additionally, in the Peruvian Amazon, Mayor et al. (2009) estimated an annual reproductive production of 0.89 parturitions and 0.62 young per adult female, and no seasonal reproductive pattern was observed. A sex ratio of 1:1 was reported in pregnant females hunted in the Peruvian Amazon (Gottdenker and Bodmer 1998, Mayor et al. 2009) and in the Mexican dry forest (Reyna-Hurtado et al. 2009). However, other estimates in free-ranging individuals showed a sex ratio biased towards females in the Pantanal (ranging from 1.36:1 to 1.88:1, female-male ratio) (Biondo et al. 2011), and this was also seen in other biomes (Fragoso 1994, Painter 1998, Altrichter et al. 2001b, Jácomo 2004). The White-lipped Peccary is a highly precocial species and presents a high morphological preparation for the early autonomous functionality of newborns in terms of thermoregulation, nutrition, locomotion and sensory processing. Consequently, newborns possess a relatively high ability to detect and escape from predators, reducing their rate of predation (de Andrade et al. 2018, de Souza-Pereira et al. 2021). Generally, the young nurse for about six months and reach sexual maturity between one and two years of age (Schmidt 1990, March 1993). Using paternity and maternity testing, Leite et al. (2018) indicated that both males and females have offspring with multiple partners, demonstrating a promiscuous genetic mating system, a similar pattern observed in collared peccaries (Cooper et al. 2011).

White-lipped Peccaries are confined to the Neotropical Region, from southeastern Mexico in the north, through Central America and northern and central South America, as far south as Entre Rios in northern Argentina and Rio Grande do Sul in southern Brazil (Sowls 1997). To date, it has been proposed that there are five subspecies of the White-lipped Peccary, but this has not been validated through genetic and/or morphological research (Groves and Grubb 1993, Taber et al. 2011). Limited chromosome (Giannonil et al. 1981, Benirschke and Kumamoto 1984) and DNA (Gongora and Moran 2005) studies have revealed polymorphisms and some variation in sequence divergence among a few individuals from different geographical regions.

Tayassu pecari was introduced to Cuba in 1930 (Mayer and Wetzel 1987) but is no longer found in the wild there. It is presumed to be extirpated from El Salvador, and its range has been significantly reduced in Mexico, Central America, and southern South America in the last 20 years (Leopold 1959; Reyna-Hurtado et al. 2009, 2010; Altrichter et al. 2012; Thorton et al. 2020). The Amazonian populations are the largest and range over an area of 6.7 million km².

Traditionally, they range from sea level to over 1,900 m on the eastern slopes of the Andes.

White-lipped Peccary conservation depends on maintaining protected areas, degraded habitat restoration, and hunting management. This species occurs in numerous protected areas throughout its extensive range; however, it is uncertain whether the existing network of reserves is adequate to ensure the survival of representative populations sufficient in size to maintain their viability in all major habitat types across its distribution (Altrichter et al. 2012, Oshima et al. 2021, Keuroghlian et al. 2023). It is also doubtful if most reserves are large enough to maintain large herds, or if there is sufficient connectivity between reserves to allow recovery when epizootic events or population crashes occur. This is of particular concern in Central America (March 1993, Meyer et al. 2019). Ecological corridors should be prioritized to maintain connectivity between populations in fragmented habitats, particularly linking larger forest fragments (Falconi-Briones et al. 2024). For instance, wildlife crossings, such as green bridges, overpasses, tunnels, viaducts, and culverts, should be implemented near highways to provide safe passage (Mozart et al. in press). Mozart et al. (in press) used land use and land cover maps, along with population genetic data, to examine the impact of non-forested areas on the genetic connectivity of white-lipped peccaries in the Pantanal floodplain and the surrounding Cerrado plateau in central-western Brazil. Their analysis focused on patterns of genetic relatedness within these landscapes, investigating how land use and land cover affect resistance to gene flow. When comparing herds from each environment, they found that individual peccaries within herds were less genetically related in the Pantanal than in herds on the Cerrado plateau. This suggests that in the less fragmented Pantanal floodplain, there is greater movement between herds and higher genetic variability within herds. In contrast, White-lipped Peccary movements are more restricted on the fragmented Cerrado plateau, where fewer individuals can disperse between herds. Forest fragmentation reduces encounters between herds, limiting the exchange of genetic material and disrupting gene flow (Biondo et al. 2011, Maciel et al. 2019, Mozart et al. in press). With ongoing fires continuing to devastate White-lipped Peccary populations, creating climate adaptation corridors has become essential for building climate resilience (Mozart et al. in press). Effective resilience plans must include strategies for conserving habitat diversity. Wide-ranging species like the White-lipped Peccary need to escape routes, which are often lacking. Reforesting potential corridors is crucial for facilitating their movement and ensuring their survival.

Beyond protected areas, Indigenous Territories in the Amazon basin are typically large, and while white-lipped peccaries are a preferred subsistence hunting species in these management units, in the Amazon these hunting practices are often sustainable, and crucially, Indigenous Territories maintain forest cover to the same degree as protected areas. In the Peruvian Amazon, white-lipped peccaries are hunted for subsistence, which has been monitored for the past 25 years by the Peruvian Forestry and Wildlife Service, wildlife biologists, and Indigenous communities (Fundamazonia 2023). Some communities have official wildlife management plans that regulate hunting and facilitate a legal sale of part of the harvest (DICREL/ACRCTT 2022). Wildlife management plans also incorporate habitat conservation and avoid deforestation (Bodmer et al. 2023).

Peccary pelts were exported from many central and South American countries during the first half of the 20th century, before the implementation of CITES in 1973. During the 1960s and 70s many countries began to prohibit the export of peccary pelts, and in 1986, collared and white-lipped peccaries were included on Appendix II of CITES. Peru is currently the only range country that permits legal export of peccary pelts, and hides can only be exported if they originate from subsistence hunters living in the Amazonian region (Fang et al. 2008). Other countries, including Argentina, are exploring prospects for developing a managed commercial harvest of peccary hides for export. However, the low quality of White-lipped Peccary pelts and the shrinking demand in Europe for peccary leather have made the pelt trade virtually non-existent, and the past threats from pelt exports have dissipated (Fundamazonia 2023). White-lipped Peccaries are widely maintained in captivity in their countries of origin, but very rarely elsewhere, mainly because of the stringent veterinary restrictions placed on the movement of live animals into countries with significant domestic pork industries.

Research into the biology and ecology of the White-lipped Peccary is essential for developing informed, comprehensive conservation strategies. It is evident that the movement behaviour of white-lipped peccaries is influenced by environmental and landscape variables. Gaining a deeper understanding of their movement patterns, the environmental and biological triggers, and the ecological consequences of these movements, remains a priority. Significant progress has been made in population genetics analyses in Brazil, highlighting the crucial role of genetic diversity and the relationships within and among herds for guiding effective management, especially in rewilding initiatives. Agriculture and paved roads in the Cerrado highlands limit gene flow, increasing the vulnerability of White-lipped Peccary to loss of genetic variability and local extinctions (Mozart et al. in press). We must also learn how to manage White-lipped Peccary populations living in and around farming areas, where they eat cultivated corn. Such management efforts would reduce conflict with plantation owners (Costa et al. 2023, Painkow-Neto et al. 2024). Without such efforts, White-lipped Peccary may be extirpated from those regions.

Additionally, investigating the adaptive strategies that allow herds to persist amid climate change, agricultural expansion, poaching, and fragmented or human-modified habitats is critical. Understanding these survival mechanisms and identifying the factors that facilitate coexistence between white-lipped peccaries and humans is fundamental for implementing conservation measures that ensure sustainable coexistence and the long-term preservation of these populations.

The most important research need for this species is related to the sudden disappearances and reappearances across its range (Fragoso et al. 2022). Anecdotal evidence from Bolivia suggests that White-lipped Peccary herds collectively left large areas, with parallel appearances in other areas hundreds of kilometres away. Intriguingly, several Indigenous Peoples in the same region have oral traditions that speak of white-lipped peccaries disappearing and reappearing from the ground at mineral licks, and ceremonies to ask for white-lipped peccaries to return. Could white-lipped peccaries engage in possible long-term and long-distance migration behaviour or are these simply population-dispersal events? These possibilities or alternative explanations require confirmation, as the conservation implications of long-distance migrations would be enormous.

Infectious diseases are probably involved in the local episodes of the disappearances of White-lipped Peccary populations. However, their impact has not yet been well evaluated. Many studies are opportunistic, with small sample sizes and in captive populations. In future research, it is important to focus on the impact of infectious diseases on the conservation of peccary species and develop longitudinal studies with a broader geographic coverage in coordination with local research groups and including multidisciplinary approaches. Likewise, it is necessary to advance local and regional studies on infectious diseases in domestic pigs that reveal possible emerging pathogens.

Research on White-lipped Peccary management, conservation, ecology, and biology has expanded in recent years. A range wide status assessment on this species has been completed, based on a workshop held in 2005, where the historical and current status and distribution data were compared, and the main threats and population status were determined (Altrichter et al. 2012). However, this assessment needs to be updated, and research, management, and monitoring capacity are lacking in many of the range countries. Capacity building of conservation biologists, local and national government technicians, and community para-technicians is a high priority for the species. There is also a need for a review of national and local government policies and regulations for this species across its range.