Around half of the 18 or so species in the pig family (Suidae) are in the genus Sus. By far the best known and widely distributed pig is the Eurasian Wild Pig or Wild Boar (Sus scrofa). Indeed, this species has one of the largest geographic ranges of any mammal.The enormous geographic variation in appearance--amplified by the intentional and accidental release of wild, domesticated, and hybrid forms across various parts of the range--led to the description of a large number of putative species and subspecies now widely viewed as invalid (although new data and analysis may yet result in the revival of some of these names).
Before human intervention, this species was present from the British Isles in the extreme west through Eurasia from southern Scandinavia to southern Siberia and extending as far east as Korea and Japan and southeast to some of the Sunda Islands and Taiwan. To the south, this species ranged along the Nile valley to Khartoum and north of the Sahara in Africa and roughly followed the continental coasts of south, east, and southeast Asia. Within this range, it was absent only from extremely dry deserts, such as the driest regions of Mongolia, and alpine zones such as the high altitudes of the Pamir Mountains.
In recent centuries, humans have had a dramatic impact on the distribution of the Eurasian Wild Pig through hunting and habitat modification. The Eurasian Wild Pig disappeared from the British Isles in the 17th century and from Denmark in the 19th century and during the 20th century its numbers and distribution declined over much of its range in locations as far-flung as Tunisia, Sudan, Germany, and Russia. In the mid-20th century, there were moderate population recoveries following these severe declines in Russia, Italy, Spain, and Germany and both natural and assisted range expansions in Denmark and Sweden. The species has also been accidentally reintroduced to Great Britain via escapes of mixed-origin pigs from commercial farming operations.Introduced feral populations derived from this species are serious pests causing severe ecological disruption in many parts of the world including Australia, New Zealand, the eastern Malay Archipelago, North America, Central America, and South America, among others.
The Eurasian Wild Pig is ecologically flexible and may be found in habitats ranging from closed natural and planted forests to open scrublands with some cover. In Europe, they are found in agricultural landscapes as well as riverine and mountainous forests, reaching especially high densities in oak-dominated forests. In Southeast Asia, this species may be found in mature forests, secondary forests, gardens, and plantations. It can reach very high densities in dipterocarp forests during periods of mast-fruiting. Although these wild pigs generally avoid open agricultural fields, when crops are taller they may enter fields and cause considerable damage.
The diet of the Eurasian Wild Pig is extremely varied and can even include young deer and lambs.The pigs themselves may be preyed upon by Gray Wolves, Dholes, Tigers, Leopards, Eurasian Lynxes, and large reptiles such as crocodiles and pythons.
The gestation period is around 112 to 130 days. Litter size is typically between five and nine young, each piglet weighing 750 to 1000 g at birth. The piglets begin to eat solid food, such as worms and grubs, at about 2 weeks and are weaned at 3 to 4 months. Eurasian Wild Pigs may live over 20 years in the wild. Adults are dangerous when they feel threatened. A male will lower its head, charge, and slash upward with his tusks; a female, whose tusks are not visible, will charge with her head up, mouth open, and bite.Eurasian Wild Pigs tend to be most active between dusk and dawn.
Although this species is secure globally, many local populations are vulnerable due to hunting pressure as well as hybridization with domestic and feral pigs.
There are an estimated 2 billion domesticated pigs on our planet, which are derived mainly from Eurasian Wild Pigs and Sulawesi Warty Pigs (Sus celebensis). There is evidence that local pigs were domesticated independently in Europe, Asia Minor, the Far East (including Japan), and various parts of Southeast Asia. The earliest evidence of domestication dates back more than 10,000 years.
(Meijaard et al. 2011 and references therein)
Feral swine, also known as feral pigs or wild boars, is a designation that can be applied to introduced Eurasian boars, escaped or released domestic pigs, and cross-breeds of the two. Eurasian boars were introduced to North America as early as 1539 as domestic pigs; additional introductions of other wild Eurasian boar races for hunting occurred through the1800’s and 1900’s. New York populations of feral swine have most likely emerged from escaped and abandoned Eurasian boars kept in captivity and at hunting preserves. Feral swine crossbreed readily with domestic pigs, which has resulted in a wide range of coat colors and body shapes. Many look like typical wild boars, while others may be hard to distinguish from domestic pigs. Known breeding populations of feral swine in NY (2011) include northwest Cortland, southwest Onondaga, and southern Tioga counties. Pennsylvania also has well established populations in 18 or more counties. Swine may be seen in several Southern Tier border counties with Pennsylvania. Feral hogs have also been observed in a few upstate counties associated with hunting preserves.
Biology
Feral pigs can breed at any time with a gestation of 115 days. A female is sexually mature at 1 year of age. Litter sizes range from 1-8 piglets; sows aggressively protect their young. Due to their hardiness and ability to adapt to a wide range of weather conditions and food sources, feral swine can triple their population in a year. Sows average 110 pounds and boars 130 pounds, but can reach up to 400 pounds. They can be spotted, belted, or striped, entirely brown or domestic looking. Their razor sharp tusks can be 5 inches long before breaking or wearing down. Swine use their tusks to defend themselves and to establish dominance. In NY, the adults have few predators to control herd size.
Impacts Feral swine (Sus scrofa) have a list of environmental, agricultural and human impacts including:
Signs of Feral Swine
Feral swine are nocturnal; rooting and wallowing in fields and forests, eating crops and hunting. They can decimate acres of fields and gardens every night. Their rooting furrows, 2 to 8” deep, leave a “plowed” look to the landscape. Their tracks and impressions of their coarse hair can be seen at wallowing holes, creeks and mud holes. After wallowing, which can destroy habitat, they often rub the mud onto nearby trees. Swine tracks are similar to deer tracks, but more rounded. Swine scat can resemble deer, dog and human scat.
Management
In New York, anyone with a small game license may hunt and keep feral swine year round with no limit. To prevent the spread of disease, wear plastic or rubber gloves while dressing the animal, and bury the offal. Do not feed raw meats or organs to pets or livestock and thoroughly cook the meat before consuming. Feral swine may be excluded from gardens and domestic hog pens with very heavy duty fencing, but since they can burrow, fencing should be monitored. Domestic swine should be securely enclosed. Shooting can be used to remove one or two feral hogs, but trapping is recommended for removing family groups. Specially-designed corral traps with heavy metal fencing and mechanical doors are needed to capture free-ranging swine.
Reporting
If you see, shoot, or trap feral swine please report it to your regional NYS DEC Wildlife office http://www.dec.ny.gov/about/50230.html. It is important that natural resource managers know where the swine are. Feral swine are a threat to New York’s landscape and agriculture. They can cause an immense amount of damage in a short period of time and can transmit disease. Please do not intentionally release swine into the wild for hunting and keep an eye out for escaped domestic pigs. Eradication of feral swine is important.
