Étude de cas sur les impactsAustralia 
Altération d'habitat: Fleay’s Barred-frog (Mixophyes fleayi) is listed as 'Endangered (EN)' in the IUCN Red List of Threatened Species. Endemic to Australia it occurs in wet forests from the Conondale Range in south-east Queensland, south to Yabbra Scrub in north-east New South Wales. While the specific reason for its decline is not known large areas of its habitat are being degraded and altered due to urban encroachment, forest logging, trampling and rooting by pigs (Sus scrofa) and domestic stock; and the invasion of alien invasive weeds like mistflower (Ageratina riparia) and crofton weed (Ageratina adenophora). The Chytrid fungus (Batrachochytrium dendrobatidis) has been identified as the cause of illness and death in some populations (Hines et al 2004).
Altération d'habitat: The Southern Gastric Brooding Frog (Rheobatrachus silus) is listed as 'Extinct (EX)' in the IUCN Red List of Threatened Species. Endemic to Australia it occured in the Blackall and Conondale Ranges in south-east Queensland inhabiting streams and catchments of the Mary, Stanley and Mooloolah Rivers. It has not been recorded in the wild since 1981. The reasons for its decline are unknown; the Chytrid fungus (Batrachochytrium dendrobatidis) is suspected to have caused declines in populations. Its habitat is also degraded due to trampling and rooting by pigs (Sus scrofa) and the spread of the alien mistflower (Ageratina riparia) (Meyer et al 2004)
Altération d'habitat: The Mount Glorious Day Frog (Taudactylus diurnus) is listed as 'Extinct (EX)' in the IUCN Red List of Threatened Species. An Australian endemic, it occurred in disjunctive populations in three sub-coastal mountain ranges (Blackall, Conondale, and D’Aguilar Ranges) in the south-east Queensland region from Coonoon Gibber Creek in the north to Mount Glorious in the south. It has not been recorded in the wild since 1979. The reasons for its decline are unknown; the Chytrid fungus (Batrachochytrium dendrobatidis) is suspected to have caused declines in populations. Its habitat is also degraded due to trampling and rooting by pigs (Sus scrofa) and the spread of the alien mistflower (Ageratina riparia); Lantana (Lantana camara) and the alien grass Baccharis halimifilia. Frog populations were absent where pigs had caused damage and where alien plants had invaded (Hero et al 2004). Nuku Hiva Is. (French Polynesia)
Menace pour les espèces en danger: Grazing by feral pigs pose a major threat to the survival of the monotypic 'Critically Endangered (CR)' palm Pelagodoxa henryana (Johnson 1998) French Polynesia 
Altération d'habitat: L’impact du cochon sur la biodiversité de ces îles n’a pas fait l’objet de travaux à ce jour. Des forêts naturelles ombrophiles sont dévastées par des cochons sauvages sur les sommets de Hiva Oa et les plateaux d’altitude du Temehani à Raiatea (Meyer, pers. comm., 2007).
Interaction avec d'autres espèces envahissantes: L'implication des cochons dans la dissémination des graines de plantes exotiques envahissantes a été observée pour Syzygium cumini dans l’île de Hiva Oa, pour Miconia calvescens et Psidium cattleianum à Raiatea, et pour Chrysobalanus icaco à Raiatea et Fatu Hiva aux Marquises (Meyer, 2004a, et pers. comm., 2007). Montserrat
Altération d'habitat: Sus scrofa uproot patches of Heliconia caribbea plants, the main nest plants for the 'Critically Endangered (CR)' endemic Montserrat oriole (see Icterus oberi in IUCN Red List of Threatened Species) and a valuable food source for nectarivorous birds and insects. Loss of this plant may also increase soil erosion and flooding downstream (Pers.comm., Hilton, 2004 in Varnham, 2006)
Menace pour les espèces en danger: Sus scrofa are believed to trample and predate turtle nests (Martin, 2003 in Varnham, 2006). Marine turtles that nest in Montserrat include the 'Critically Endangered (CR)' Hawksbill turtles (see Eretmochelys
imbricata in IUCN Red List of Threatened Species); the 'Endangered (EN)' green turtle (see Chelonia
mydas in IUCN Red List of Threatened Species); the 'Endangered (EN)' loggerhead turtle (see Caretta
caretta in IUCN Red List of Threatened Species) and the 'Critically Endangered (CR)' leatherback turtle (see Dermochelys
coriacea in IUCN Red List of Threatened Species).
S.
Scrofa are thought likely to predate slower moving herpetofauna, such as 'mountain chicken' the near-endemic 'Critically Endangered (CR)' (see Leptodactylus
fallax in IUCN Red List of Threatened Species), and perhaps, if they enter its range, the endemic Montserrat galliwasp (see Diploglossus
montisserrati in IUCN Red List of Threatened Species) (Pers.comm., Hilton, 2004 in Varnham, 2006).
S. scrofa are likely to directly destroy mountain chicken nests by their extensive digging and wallowing along watercourses (Pers.comm., Hilton, 2004 in Varnham, 2006).
Modification de l'écosystème: Sus scrofa In medium-long term they are likely to have a very major impact on forest ecology, in particular through arresting tree succession (by eating seedlings) (Pers.comm., Hilton, 2004 in Varnham, 2006).
Réduction de la biodiversité indigène: Sus scrofa are often reported as eating large numbers of terrestrial arthropods (though population impacts under-recorded). New Caledonia (Nouvelle Calédonie)
Compétition: Warner (1948) mentions several introduced species as predators of a native bird called the kagu (Rhynochetos jubatus see in IUCN Red List of Threatened Species). “Escaped pigs and the introduced rats are … causing heavy damage to the kagu at the present time. They not only kill the birds but also destroy its food supply of land snails and large earthworms…. I often found snail shells in rat runways and burrow entrances and scattered about in other odd places. Many of these had been gnawed in typical rat fashion.… The pig and rat may also take young birds and eggs …"
Prédation: Warner (1948) mentions several introduced species as predators of a native bird called the kagu ("http://www.iucnredlist.org/details/143794/0">Rhynochetos jubatus see in IUCN Red List of Threatened Species). “Escaped pigs and the introduced rats are … causing heavy damage to the kagu at the present time. They not only kill the birds but also destroy its food supply of land snails and large earthworms…. I often found snail shells in rat runways and burrow entrances and scattered about in other odd places. Many of these had been gnawed in typical rat fashion.… The pig and rat may also take young birds and eggs …" Grand Terre Is. (New Caledonia) (New Caledonia (Nouvelle Calédonie))
Réduction de la biodiversité indigène: L’impact négatif du cochon est avéré sur la malacofaune, notamment sur les bulimes (Brescia, 2005) et fortement suspecté sur la microfaune terrestre, sur certains oiseaux nichant au sol ainsi que sur de nombreux fruits, graines et tubercules de plantes (Pascal et al., 2006). Hawaiian Islands (United States (USA))
Perturbation physique: “Watersheds, forests, and range are damaged when pigs root excessively ….” On Hawai‘i, with the control of feral goats and the elimination of feral sheep from certain habitats, the feral pig “has emerged as the most prominent agent of ecological perturbation, of wet forests in particular”.
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