Collared peccary (Pecari tajacu) is a medium‑sized even-toed ungulate belonging to the family Tayassuidae, order Artiodactyla. It inhabits a broad swath of the Americas, from the arid deserts of the southwestern United States through Mexico, Central America, and into the tropical lowlands and highland forests of South America as far south as northern Argentina. The species thrives in diverse habitats, including scrub‑grasslands, thorn‑scrub, tropical dry forest, and even cultivated agricultural areas, demonstrating remarkable ecological flexibility. Adults are distinguished by a conspicuous white or light‑gray band of hair encircling the neck, giving the animal its common name. Both sexes possess elongated, curved canine tusks that protrude from the upper jaw and are used for foraging and defense. Their coarse, bristly coat varies from reddish‑brown to gray, providing camouflage across varied substrates. Collared peccaries are primarily nocturnal to crepuscular, forming stable groups that enhance predator detection. The IUCN classifies the species as Least Concern due to its wide distribution and large, stable populations, although localized declines occur where hunting pressure and habitat conversion are intense.

Collared peccaries live in cohesive social units called herds, typically comprising 5–15 individuals but occasionally reaching up to 30 in resource‑rich areas. Herd composition is fluid; females and their offspring form the core, while adult males may be solitary or temporarily associate during the breeding season. The species is crepuscular to nocturnal, with peak activity at dawn and dusk when they forage for food and water. Home ranges vary from 0.5 to 3 km² depending on habitat productivity, and individuals defend these areas through scent marking, vocalizations, and occasional aggressive encounters. Communication relies on a repertoire of grunts, squeals, and high‑pitched whistles that convey alarm, cohesion, or reproductive intent. When threatened, peccaries form a defensive circle, presenting their tusks outward to deter predators such as coyotes, jaguars, and large raptors. Their strong social bonds and coordinated vigilance enable effective predator avoidance and resource exploitation across heterogeneous landscapes.

Collared peccaries are opportunistic omnivores, consuming a varied diet that reflects seasonal availability. Plant material dominates, including fruits, seeds, tubers, cactus pads, and succulent leaves; they are particularly fond of mesquite pods, agave hearts, and palm fruits. In arid habitats, they supplement with roots and underground storage organs, digging with their snout and forefeet. Animal matter accounts for up to 15 % of intake and comprises insects, small vertebrates, carrion, and eggs. During the dry season, peccaries increase consumption of cactus water and succulent tissues to meet hydration needs, often traveling long distances to locate water sources. Foraging is primarily nocturnal, reducing competition with diurnal herbivores and minimizing predation risk. Their robust dentition, featuring sharp incisors and curved canines, allows them to process tough fibrous material and break open hard‑shelled fruits, while their keen sense of smell guides them to hidden food caches.

Females reach sexual maturity at 12–18 months, while males mature slightly later at 18–24 months. Breeding occurs year‑round in tropical regions, but in temperate zones a seasonal peak aligns with the rainy season, ensuring abundant forage for lactating females. After a gestation period of 144–152 days, a single fawn is born, though twins are reported in up to 5 % of litters. Newborns weigh 2.5–3.5 kg and are precocial, standing and following the mother within hours. The mother nurses the fawn for approximately 3–4 months, after which the young are weaned but remain with the natal herd for several years, learning foraging techniques and social cues. Longevity of reproductive capacity extends to about 8–10 years in the wild, with females typically producing 2–3 offspring over their lifetime. Males may sire multiple litters per year, especially when dominant during the breeding season.

The IUCN lists the collared peccary as Least Concern, estimating a global population of several million individuals, yet regional pressures threaten local subpopulations. Primary threats include unregulated hunting for meat and hide, habitat loss from agricultural expansion, urbanization, and mining activities that fragment the scrub‑grassland mosaics they depend on. In the United States, vehicle collisions and disease transmission from domestic livestock pose additional mortality factors. Climate change may exacerbate water scarcity in desert ranges, forcing peccaries to shift their distribution upward in elevation or toward human‑dominated landscapes, increasing human‑wildlife conflict. Conservation measures focus on sustainable harvest regulations, protected area designation, and community‑based monitoring programs. In Mexico and Central America, several national parks and biosphere reserves maintain stable peccary populations, and recent population surveys in the Sonoran Desert indicate a modest increase following the implementation of hunting quotas.

• Collared peccaries can run up to 48 km/h, allowing rapid escape from predators.
• They possess a unique “collar” of white hair that can vary in thickness with age and season.
• Peccaries are one of the few ungulates that actively dig for water and underground tubers.
• Their social defense circle can deter large predators such as jaguars and coyotes.
• Unlike true pigs, collared peccaries have a split upper lip that enhances their ability to root in sandy soils.