General Impact
The small Indian mongoose has had a major impact on native species in the areas where it has been introduced. In most cases the native wildlife in these areas evolved in the absence of predatory mammals so they are particularly threatened by mongoose predation. Species considered to have been driven extinct through mongoose predation are the barred-wing rail (see Nesoclopeus poecilopterus in IUCN Red List of Threatened Species) in Fiji (Hays and Conant, 2007). The Critically Endangered (CR)' and 'Possibly Extinct' Jamaica petrel (see Pterodroma caribbaea in IUCN Red List of Threatened Species) suffered drastic decline in numbers in the 19th century presumably due to predation by mongoose (capable of taking incubating adults) and rats (BirdLife International 2004). Mongooses have also been implicated in the decline of many other bird, reptile and mammal species. Mongooses also eat invertebrates but the impact of this predation on invertebrate populations has not been studied.
In the Caribbean, mongooses prey on the 'Critically Endangered (CR)' hawksbill turtle (see Eretmochelys imbricata in IUCN Red List of Threatened Species) eggs in fragmented beach habitat (Leighton et al 2008, 2009, 2010, 2011) . Trapping around vulnerable beaches led to much greater breeding success for the turtles (Coblentz and Coblentz, 1985).
Mongooses on Mauritius have been blamed for the extirpation of introduced game birds and the decline of endemic species such as the 'Endangered (EN)' pink pigeon (see Nesoenas mayeri in IUCN Red List of Threatened Species) (Roy et al. 2002).
At least seven species of native vertebrates, including mammals, birds, reptiles, and amphibians, have almost disappeared on Amami-oshima Island since the introduction of the mongoose in 1979. The mongoose has been shown to have a strong negative effect on the 'Endangered (EN)' Amami rabbit (see Pentalagus furnessi in IUCN Red List of Threatened Species) (Watari et al. 2008). In addition, mongoose are carriers of human and animal diseases, including rabies and human Leptospira bacterium.
Location Specific Impacts:British Virgin Islands 
Predation: The small Indian mongoose has caused the near-extinction of the ground-nesting quail dove (Geotrygon mystacea) in the British Virgin Islands. A study by Small (1982) in the Virgin Islands National Park, showed that 23% of the eggs and hatchlings of 'Critically Endangered (CR)' hawkesbill turtles (Eretmochelys imbricata) were destroyed by mongooses (SPREP, 2000). Viti Levu Is. (Fiji)
Predation: Mongooses are believed to be largely responsible for the extirpation of the two largest skink, Emoia nigra and E. trossula from two of the largest Fijian islands, Viti Levu and Vanua levu. The species which are still to be found on mongoose free islands, disappeared from these islands a few years after the arrival of the mongoose (Hays and Conant 2007). There is circumstantial evidence for implicating the small Indian mongooses in the decline of several species of ground-dwelling birds (Pernetta and Watling 1978); four birds, the 'Least Concern (LC)' buff-banded rail (Gallirallus philippensis), the 'Least Concern (LC)' Spotless crake (Porzana tabuensis), white-browed rail Poliolimnas cinereus and the purple swamp hen (Porphyrio porphyrio which are present on mongoose free islands were extirpated from Fijian islands where mongoose are present (Hays and Conant 2007). Fiji
Predation: Small Indian mongooses are believed to be largely responsible for the extirpation of the two largest skinks, Emoia nigra and E. trossula from two of the largest Fijian islands, Viti Levu and Vanua levu. The species which are still to be found on mongoose free islands, disappeared from these islands a few years after the arrival of the mongoose (Hays and Conant 2007). Grenada
Predation: Chapter III of the 'Inventory and status of the natural and cultural resource base of the The National Parks and Protected Areas System Plan' reports that Garman's ground lizard - Ameiva ameiva or zaggada, a handsome blue coloured lizard, (male) now found only in Grenada and the Grenadines was almost brought to extinction by the mongoose. The red-humped agouti (Dasyprocta liporina) is extinct on the Island due to overhunting and the aggressive mongoose (Beresford Wilcox, Pers. Comm.) Guadeloupe 
Disease transmission: The mongoose is a reservoir and vector of pathogenic forms of the bacteria Leptospira interrogans responsible for leptospirosis disease, which has a rate of prevalence in Martinique and Guadeloupe forty times higher than in metropolitan France (Lorvelec et al., 2004).
Reduction in native biodiversity: The mongoose has contributed to the demise of the burrowing owl (Speotyto cunicularia), the extinction of the lizard Ameiva juliae and the sharp decline in populations of two species of snakes (Liophis juliae) and the 'Endangered (EN)' (Alsophis sanctonum =Alsophis antillensis) and the Mabuya skink (Mabuya mabuya) (Lorvelec et al, 2004) . Fajou Is. (Guadeloupe)
Predation: The small Indian mongoose eradication and the sharp decline in the ship rat population, ended the destruction of the 'Critically Endangered (CR)' hawksbill turtle nests (Eretmochelys imbricata), and led to a re-colinisation of the dryer parts of the island by the clapper rail (Rallus longirostris), which had been strictly confined to the mangroves. The abundance indicies of the clapper rail and the terresrial crab Cardisoma guanhumi increased. More data is required to test the actual relationship between these increases and the reduction in alien mammal populations (Lorvelec et al. 2004). Amami Is. (Japan)
Agricultural: The small Indian mongoose has a large impact on crops (taro, sweet potato, melon, watermelon, loquat, etc.) and poultry in
farmland. The economic cost of the damage rapidly in-creased
in 1994 (USD7000), 1995 (USD32,000), 1996
(USD64,000), 1997 (USD110,000), 1998 (USD100,000)
and 1999 (USD80,000).
Predation: The small Indian mongoose has had a predatory impact on native animals in the mountainous areas of the island where it has spread since 1986. Threatened native species that have been recorded in the diet of the mongoose include: the 'Endangered (EN)' Ryukyu rat (Diplothrix legatus); the 'Endangered (EN)' Ryukyu spiny rat (Tokudaia osimensis); the 'Endangered (EN)' Amami rabbit (Pentalagus furnessi); the 'Endangered (EN)' Ryukyu woodcock (Scolopax mira; the 'Vulnerable (VU)' Amami jay (Garrulus lidthi); the 'Near threatened' (NT) Ryukyu robin (Erithacus komadori); reptiles Japalura polygonata, Barbour's Eyelid Skink (Eumeces barbouri), Calliophis japonicus japonicus, Cyclophiops semicarinatus; and the mammal Crocidura horsfieldii watasei (Yamada, 2002). Martinique
Disease transmission: The Mongoose is a reservoir and vector of pathogenic forms of the bacteria Leptospira interrogans responsible for leptospirosis disease, which has a rate of prevalence in Martinique and Guadeloupe forty times higher than in metropolitan France (Lorvelec et al., 2004).
Threat to endangered species: The introduction of the mongoose is particularly cited as leading to a scarcity of certain species of herpetofauna and bird nesting on the ground or close to the ground, such as the 'Endangered (EN)' White-breasted thrasher (Ramphocinclus brachyurus). Hawaii (United States (USA))
Threat to endangered species: Small Indian mongooses are known to eat the young of the now 'Extinct in the Wild (EW)' Hawaiian crow (see Corvus hawaiiensis) (Giffen 1983 in Stone 1984) and both eggs and incubating females of the 'Vulnerable (VU)' Nene goose (Branta sandvicensis) (Banko 1982). Mongooses have had severe negative impacts on the the US Endangered Hawaiian Dark-rumped Petrel (Pterodroma phaeopygia sandwichensis) (Baldwin et al 1952) (SPREP, 2000).
The Draft Revised Recovery Plan for Hawaiian Forest Birds by U.S. Fish and Wildlife Service reports that 21 taxa of endemic birds are threatened in Hawaii. Predation is one of the causes and the mongoose is listed as one of the several predators. Virgin Islands, USA
Predation: Small Indian mongooses caused the near-extinction of the ground-nesting quail dove (Geotrygon mystacea). A study by Small (1982) in the Virgin Islands National Park, showed that 23% of the eggs and hatchlings of 'Critically Endangered (CR)' hawkesbill turtles (Eretmochelys imbricata) were destroyed by mongooses (SPREP, 2000).
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