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         Management Information

    Preventative measures: Research has shown that it can often be difficult to eradicate rats from islands in the early stages of invasion, hence it is better to prevent rodents arriving on islands in the first place. Eliminating a single invading rat can be disproportionately difficult because of atypical behaviour by the rat in the absence of conspecifics, and because bait can be less effective in the absence of competition for food (Russell et al., 2005). Weihong et al. (1999) provide useful information regarding the detection of rodent species using different trapping methods and bait.

    Physical: The use of poison baits is the only proven way to remove rodents from large islands. Trapping generally fails to remove all individuals, as trap-shy animals can survive and repopulate the island (DOC, 2004).

    Chemical: Rattus rattus can be eradicated from small areas or seasonally controlled using proprietary rat poison products in an appropriate manner. The largest island to date from which ship rats have been eradicated is Barrow Island (23 000 ha, Western Australia) (Morris, 2002).

    Second-generation anticoagulant poisons are used widely for ship rat control, but possible consequences of any ongoing control should always be considered. These consequences include primary or secondary poisoning of species we are aiming to protect or other non-target species, secondary poisoning of other vertebrate pests such as cats, and development of resistance to these poisons by ship rats. It is not known whether their tree-climbing habits will make eradication more difficult (SPREP, 2000).

    Fisher et al. (2004) suggest that diphacinone especially, and also coumatetralyl and warfarin, should be evaluated in field studies as alternative rodenticides in New Zealand. Brodifacoum, the most widely used rodenticide in New Zealand currently, can acquire persistent residues in non-target wildlife. Mineau et al. (2004) presented a risk assessment of second generation rodenticides at the 2nd National Invasive Rodent Summit. O'Connor and Eason (2000) discusses the variety of baits which are available for use on offshore islands in New Zealand.

    An investigation Spurr et al. (2007) was carried out to assess the behavioural response of ship rats to four different bait station types. Yellow plastic pipe, wooden box (‘rat motel’), and wooden tunnel bait stations were found all suitable for surveillance of ship rats and the first two at least for Norway rats (all were readily entered and had a similar amount of bait eaten from them).

    Biological: Contraceptive methods of control are currently experimental, but the potential for effective control using contraceptive methods is promising. National Wildlife Research Center (USA) scientists are working on several possible formulations that may make effective oral immunisation possible (Nash and Miller, 2004).

    Integrated management: Guidelines for the Eradication of Rats From Islands Within the Falklands Group offers guidelines for the eradication of rats from islands, based on the experiences in eradicating rats from the Falklands group. This paper offers guidelines for the eradication of rats from islands, based on the experiences in eradicating rats from the Falklands group. français     



         Location Specific Management Information
    Anacapa East
    Rattus rattus was eradicated from Anacapa East in December 2001. The eradication programme was led by Island Conservation and Channel Islands National Park. One application of brodifacoum (25ppm) was carried out aerially and by hand broadcast, at a rate of 15kg/ha. The endemic mouse (see Peromyscus maniculatus ssp. anacapae in IUCN Red List of Threatened Species) was protected by staggering the eradication over the three Anacapa islets, so that a free-ranging population was always present on one or more islets. A captive population was also kept on the island (Howald et al., 2004). A number of measures are now in place to prevent reinfestation: rodent proof storage areas, rodent proof containers, and rodent control at all entry points to the island (Anacapa Island Restoration Plan Progress Report and Work Plan). This was the first aerial application of rodenticide to eradicate rats in North America. For more information on the project and project updates please see: Project update May, 2003
    Anacapa Middle
    Rattus rattus was eradicated from Anacapa Middle in November 2002. The eradication programme was led by Island Conservation and Channel Islands National Park. One application of brodifacoum (25ppm) was carried out aerially and by hand broadcast, at a rate of 15kg/ha. The endemic mouse (see Peromyscus maniculatus ssp. anacapae in IUCN Red List of Threatened Species) was protected by staggering the eradication over the three Anacapa islets, so that a free-ranging population was always present on one or more islets. A captive population was also kept on the island (Howald et al., 2004). A number of measures are now in place to prevent reinfestation: rodent proof storage areas, rodent proof containers, and rodent control at all entry points to the island (Anacapa Island Restoration Plan Progress Report and Work Plan). This was the first aerial application of rodenticide to eradicate rats in North America. For more information on the project and project updates please see: Project update May, 2003
    Anacapa West
    Rattus rattus was eradicated from Anacapa West in November 2002. The eradication programme was led by Island Conservation and Channel Islands National Park. One application of brodifacoum (25ppm) was carried out aerially and by hand broadcast, at a rate of 15kg/ha. The endemic mouse (see Peromyscus maniculatus ssp. anacapae in IUCN Red List of Threatened Species) was protected by staggering the eradication over the three Anacapa islets, so that a free-ranging population was always present on one or more islets. A captive population was also kept on the island (Howald et al., 2004). A number of measures are now in place to prevent reinfestation: rodent proof storage areas, rodent proof containers, and rodent control at all entry points to the island (Anacapa Island Restoration Plan Progress Report and Work Plan). This was the first aerial application of rodenticide to eradicate rats in North America. For more information on the project and project updates please see: Project update May, 2003
    Arizona
    Community and government campaigns in Arizona are working to suppress rat populations, although it is unknown if these efforts will be sufficient to eradicate rats from the area.
    Ascension Is.
    A study of the feasibility of totally eradicating black rats has been carried out (Bell and Ashmole, 1995 in Varnham, 2006). The Management Plan recommends monitoring rat populations on the island around new and potential seabird nesting sites, to determine future reactive control measures (Pickup, 1999 in Varnham, 2006).
    Awaiti Is.
    Awaiti Island (2 ha) was used to trial the eradication of ship rats in 1982. Simple bait stations were used, containing Talon WB 50 (brodifacoum) pellets. Follow-up monitoring confirmed eradication had been achieved. They were found to have reinvaded in 2002 (Russell and MacKay, 2005).
    Bainbridge Islets
    Fearing that the small population of endemic rodents in Santiago were under threat of extinction, scientists from CDRS have decided to create a reserve on Bainbridge islets, near to Santiago. The first stage was the eradication of the ship rats that were present on four of the six islets. The work started in 2000 and by 2002 no ship rats had been detected on two of the islets. Once the total eradication has been confirmed, the program will extend to the two other islets where there are still ship rats. Charles Darwin Foundation for the Galapagos Islands, 2003.
    Barrow Is.
    Seven mammals were considered to be non-target risks on Barrow Island - Isoodon auratus barrowensis, Bettongia lesueur, Lagorchestes c. conspicillatus, Macropus robustus isabellinus, Petrogale lateralis lateralis, Trichosurus vulpecula arnhemensis, Pseudomys nanus ferculinus, Zyzomys argurus and Hydromys chrysogaster. A trapping programme was put in place in 1983 to eliminate any rats which may have colonised from Boomerang Island. None were trapped. After rats were detected at the south end of Barrow Island in 1990, a bait station was developed which gave access to rats but prevented a range of other mammals from gaining access. The native rodents Pseudomys nanus ferculinus and Zyzomys argurus are not excluded. These bait stations, filled with pindone impregnated oat bait, on a 25 x 25m grid (Morris, 2002), were placed across the south end of the island (270 ha) in 1991. No rats have been seen on Barrow Island since May 1991. Golden bandicoots (Isoodon auratus barrowensis) and Barrow Island mice numbers declined subsequent to the baiting programme but have since recovered to pre-baiting levels. Barrow Island is now one of the largest islands in the world which is free of introduced mammals.
    Bedout Is. (Western Australian Islands)
    Ship rats were eradicated from Bedout Island in 1981, using oats vacuum-impregnated with pindone on a 25 m grid.
    Bermuda
    There is concern that they could colonise offshore islands. Eradicated from Nonsuch Island in the 1960's. Quarantine measures are in place to prevent reintroduction to Nonsuch and introduction to Castle Harbour islands. It is recommended to continue quarantine measures on offshore islands (Madeiros, 2003 in Varnham, 2006).
    Bird Is.
    Rattus rattus was eradicated from Bird Island in the Seychelles in 1996. The eradication programme was undertaken by the island owner, and led by Don Merton, at a cost of US$5000. Brodifacoum (20ppm) was distributed in bait stations on a 50 x 50m grid, as well as hand broadcast, at a rate of 15kg/ha, over a five month period (Island Conservation and Ecology Group, 2004). After the initial knockdown using the bait stations, pelleted bait was broadcast by hand at ten day intervals. Capture rates were initially extremely high, but by the third week there was no sign of any rats. Permanent bait stations are maintained on the island to prevent reinvasion (B. Simmons, pers. comm., Merton et al.., 2002).
    A number of bird species were identified as non-target risks, and it was decided that the three Aldabran giant tortoises (Geochelone gigantea) on the island would be held in captivity throughout the operation. Masking tape was stretched across the lower portion of the station opening to prevent bait being consumed by other species such as skinks. Hermit crabs were excluded by raising the station 1-2 m off the ground.
    Black Rocks Is. (Bay of Islands)
    Rattus rattus was eradicated from Black Rocks (17 islets) between 1992 and 1997, by the Department of Conservation. The techniques used included an aerial application, hand broadcast and bait stations, using the chemical control brodifacoum. It was applied at 20-40kg/ha per islet, with bait stations on a 40 x 40m grid, over a one year period. Follow up was carried out in 1995, with apples, gnaw sticks, soap and snap traps (Shaw, 1997; J. Russell, pers. comm.).
    Boodie Is.
    Rattus rattus was eradicated from Boodie Island in 1985. The eradication programme used pindone bait stations on a 25 x 25m grid, over a one year period (Morris, 1989). Bait stations were covered to protect the burrowing bettong. However, rats pulled some of the oats from under the cover, and bettongs became locally extinct on Boodie Island. They were reintroduced in 1993 from Barrow Island. No rats were trapped in trapping programmes in 1998 and 2000 (Morris, 2002).
    Boomerang Is.
    Rattus rattus was eradicated from Boomerang Island (5 ha) in 1985. The eradication programme used pindone bait stations on a 25 x 25m grid, over a one year period (Morris, 1989). Non-target species included the brushtail possum (Trichosurus vulpecula arnhemensis) and golden bandicoots (Isoodon auratus barrowensis). In 2000 the island still remained rat-free, and possums and golden bandicoots had recolonised (Morris, 2002).
    Buck Is.
    An eradication programme was undertaken in 2000 on Buck Island to remove Rattus rattus, using diphacinone (G. Witmer, pers. comm.).
    Burgaux Is.
    Rattus rattus was eradicated from Burgaux Island (0.49 ha) between 1999 and 2002, in a programme led by PNR Martinique and INRA. The methods used were trapping over twelve days, on a 30 x 30m grid, and hand broadcast of bromadiolone (50ppm) (Pascal et al.., 2004).
    Cayman Brac
    Environmental Health Section of the Government maintains a rodent control program (Morgan, 1994 in Varnham, 2006) in populated areas only.
    Central Valley
    Bait stations were used to control numbers of Rattus rattus in California's Central Valley in October-December 2003. The strategy proved effective in reducing rat numbers and their predation on nesting songbirds. The labour involved and the inaccessibility of the densely vegetated areas of riparian forests may limit the implementation of this strategy on a larger scale.
    Chagos Archipelago
    The Chagos Conservation Management Plan identified the eradication of black rats from Eagle Island (the second largest Island in the archipelago) as an urgent conservation priority. The eradication programme is ongoing. Please see the Page and Meier, 2006 for more details.
    Chumbe
    Rattus rattus was eradicated from Chumbe Island in 1997.
    Clipperton Is. français 
    Given the small size of the atoll, an attempt to eradicate black rats (Rattus rattus) seems realistic. It is very strongly recommended, especially for the conservation of seabirds that nest on Clipperton.
    Conills
    An eradication programme was undertaken on Conills Island (1 ha) in 1999 to remove Rattus rattus.
    Cox Is.
    An eradication programme was undertaken on Cox Island (10 ha) in 1995, using brodifacoum (Kaiser et al.. 1997).
    Curieuse Is.
    An eradication programme was undertaken on Curieuse Island in 2000, to remove Rattus rattus. The programme was led by the Seychelles National Parks Authority, and consisted of two aerial applications of brodifacoum (20ppm), at a rate of 23kg/ha, eleven days apart. The estimated cost of the operation was US$59,000 (Currie et al. 2003; Merton et al.. 2002; www.pestoff.co.nz). In August 2001, ship rats were discovered on Curieuse Island, and had become widespread by 2002. It is suspected that ship rats again came ashore with building materials (Merton et al.. 2002).
    Denis Is.
    An eradication programme was undertaken on Denis Island in 2000, in an attempt to remove Rattus rattus from the island. The lead agency was the Seychelles Ministry of Environment, and the programme was led by Don Merton. The cost of the operation was US$50,000. Two aerial applications of brodifacoum (20ppm) were carried out, nine days apart, at a rate of 23.6kg/ha, but eradication was not achieved (Currie et al.. 2003; www.pestoff.co.nz; Merton et al.. 2002). A further attempt was made in 2003 by the island owner, also using brodifacoum, and was this time successful in achieving eradication (G. Climo, pers. comm.).
    Diego Garcia (Chagos Archipelago)
    Some local control is ongoing on Diego Garcia. Rat eradication planned to start on Diego Garcia immediately following successful conclusion of cat eradication (BIOT Administration, 2002 in Varnham, 2006).
    Double (Moturehu) Is. (Mercury Islands)
    Ship rats were eradicated from Double Island in 1983, using oats vacuum-impregnated with pindone on a 25 m grid.
    Double Is. (Western Australian) (Western Australian Islands)
    Rattus rattus was eradicated from Double Island (35 ha) in 1983. Pindone bait stations on a 25 x 25m grid were used over a one year period (Morris, 1989).
    Duffers Reef
    An attempt to eradicate Rattus rattus from Duffers Reef (2 ha) was made in 1983, but was not successful. The attempt was led by D. Taylor, and used brodifacoum (Veitch and Bell, 1990; D. Veitch, pers. comm.). Reinvasion occurred in c. 1990 (D. Brown, pers. comm.).
    Eagle Is. (Chagos Archipelago)
    The Chagos Ecological Restoration Project was carried out during February–April 2006 with the aim of eradicating the estimated 8,000 invasive ship rats R. rattus from Eagle Island. The project was managed by Fauna & Flora International (FFI) and funded primarily by the Foreign and Commonwealth Office/DFID Overseas Territories Environment Programme and the DEFRA/FFI Flagship Species Fund, with additional support from the Chagos Conservation Trust, Syngenta, Thames Water and Wexas.

    A 30 * 30 m baiting grid was established during the first 6 weeks, by cutting 82 km of transects by hand with machetes through often dense vegetation. This enabled access to all parts of the island to establish 2,844 regularly spaced baiting points. Bait was hand-broadcast between transects at regular intervals to increase coverage. The bait was 20 g wax blocks containing 0.005% brodifacoum, a second generation anticoagulant poison. The bait stations were regularly monitored, additional monitoring systems (live and snap traps, chew sticks and extensive day/night monitoring walks) were used to adapt baiting in remaining areas of activity. A post-eradication visit is due later in 2006 to confirm the eradication of the Eagle Island rat population. Please see Page and Meier (2006) for more details.

    Eagle Is. (Chagos Archipelago)
    Rat eradication is proposed for Eagle Island, the only rat-infested island in the Chagos bank sub-group (Varnham, 2003 in Varnham, 2006), currently seeking funding. A study was carried out into feasibility of removing rats from Eagle Island (Varnham, 2003 in Varnham, 2006).
    Europa Is. (Îles Éparses (Scattered Islands)) français 
    Several actions were begun in 2007, among them the rehabilitation of Europa with the eradication of Rattus rattus, Capra hircus and sisal (Agave sisalana ). The remoteness of these islands, their limited size and the lack of civilian populations, make them remarkable "study" sites for actions to control introduced invasive animal populations.
    Fajou Is. (Reserve Naturelle du Grand Cul-de-sac Marin)
    In March 2001, an attempt was made to eradicate the Javanese mangoose (Herpestes javanicus), the ship rat (Rattus rattus) and the house mouse (Mus musculus) from Fajou island in Guadeloupe. A follow up in December 2001 and January 2002 showed that the ship rat eradication had failed. There was a second attempt at eradicating the ship rats in March 2002, but it seems that it also failed. However it confirmed the success of the mongoose operation using traps alone. The success of the March 2001 house mouse operation using trapping and poisoning (Bromadiolone concentration 50 ppm, hand broadcast ) could not be properly evaluated (Lorvelec, O., et al.. 2004).
    Falkland Islands (Malvinas) (sub-Antarctic)
    Selective trapping & research programmes are ongoing. Further selective trapping & possible control is being considered/required. Eradication from all New Island may be considered in future.
    Feno Islet (Terceira Is. Terceira Is.)
    The eradication of the black rat from Feno Islet was initiated in 2006. An evaluation of rat numbers was undertaken in 2006 which indicated that the population size was small. Mass trapping was undertaken in early 2007 with the setting of 140 Sherman traps baited with cheese. Monitoring using the same trapping method continued till the end of 2008. No rats were detected 17 months after the last rat was caught. The black rat is now declared eradicated from Feno Islet.
    Please follow this link for a description of the eradication process (Amaral et al 2010)

    Roseate and common terns have recolonised Feno. By 2009 three years after eradication Feno once again hosts the largest colony of roseate terns on the Azores. Close monitoring is critical to prevent reinvasion of rats from the nearby main island of Terceira. (Amaral et al 2010).

    Flat Is. (Mauritius)
    Rattus rattus was eradicated from Flat Island in 1998, in a programme undertaken by Wildlife Management International Limited (led by Paul Bell). The methods used were brodifacoum (20ppm) and bromadiolone (50ppm) bait stations over a one year period (Bell, 2002; A. Khadun, pers. comm.). Land and hermit crabs were present on part of the island, and in order to prevent crabs taking the bait, it was necessary to raise the bait stations about 15 cm above the ground. However experience has showed the best way to overcome this problem is by simply increasing the amount of bait applied (Bell et al.. 2002).
    Folaca Is. (Cerbicales)
    Rattus rattus was eradicated from Folaca Island (0.2 ha) in 2001, in a programme undertaken by Agence Envir. Corse and INRA (led by Michel Pascal). The methods used were traps over twelve days, and hand broadcast of bromadiolone (50ppm) over 18 days, on a 20 x 20m grid (M. Pascal, pers. comm.).
    Folaccheda Is. (Cerbicales)
    An attempt was made to eradicate Rattus rattus from Folaccheda Island (0.1ha) in 2001, undertaken by Agence Envir. Corse and INRA, led by Michel Pascal. The methods used were trapping over twelve days, and hand broadcast of bromadiolone (50ppm) over 18 days, on a 20 x 21m grid, but eradication was not achieved (M. Pascal, pers. comm.).
    Fortyseven Is. (Bay of Islands)
    An attempt was made to eradicate Rattus rattus from Fortyseven Island (1 ha) in 1990 (led by D. Taylor), but was not completed (D. Taylor, pers. comm.; D.Veitch, pers. comm.).
    Gabriel Is.
    Ship rats were present on Gabriel Island in high numbers before an eradication programme was carried out in 1995, in a programme undertaken by Wildlife Management International Ltd (led by Brian Bell). The eradication was achieved using hand broadcast of brodifacoum (20ppm) and bromadiolone (50ppm) over a one year period (Bell, 2002; A. Khadun, pers. comm.). Gabriel Island is very close to Flat Island, and it was recommended that eradication be carried out there within 12 to 18 months to prevent recolonisation of Gabriel Island. Land and hermit crabs were present in high numbers, and as it was thought these may contribute to a failure of the eradication, more bait was used than would be usual. Since eradication, there has been significant regeneration of Pandanus and Latania, and an apparent increase in wedge-tailed shearwaters (Puffinus pacificus) and red-tailed tropicbird (Phaethon rubricauda) (Bell, 2002).
    Goat Is. (Leigh)
    Rattus rattus was eradicated from Goat Island in 1992, but reinvasion has since occurred. The eradication was carried out by the Department of Conservation (led by T. Wilson) (J. Russell, pers. comm.). For more information, please refer to MacKay and Russell, 2005. A further eradication attempt was made in 2005, and was declared successful (MacKay and Russell, 2005).
    Grand Cayman
    Environmental Health Section of the Government maintains a rodent control program (Morgan, 1994 in Varnham, 2006) in populated areas only.
    Great Bird Is.
    Rattus rattus was eradicated from Great Bird Island in 1995, in a programme undertaken by the Antiguan Racer Conservation Project (led by J. Daltry and M. Day). The eradication was achieved using brodifacoum (50ppm) bait stations on a 10 x 10m grid. Permanent bait stations are now in place on the island to prevent reinvasion (K. Lindsay, pers. comm.; K. Varnham, pers. comm.).
    Green Is.
    A rat eradication project was conducted by the Antiguan Racer Conservation Project (ARCP) in 2001, under the auspicies of the Caribbean Programme of Fauna & Flora International. The ARCP is funded by the Walt Disney Conservation Foundation, Durrell Wildlife Conservation Trust, Roger Vere Foundation, Lindeth Charitable Trust and the Bernhardine Fund. As is common in the Caribbean region, the ARCP aimed to eradicate both Rattus rattus and Herpestus aurupunctatus (javanicus) from Green Island, an unpopulated 43 hectare island off the Antiguan east coast. As it turned out, only Rattus rattus was found and was eradicated in 2001. The eradication was achieved over four weeks using brodifacoum (50ppm) bait stations on a 20 x 20m grid, at a cost of c. US$15,000. Non-target species included various bird species, in particular egrets and raptors such as Pandion haliaetus, Nyctanassa violacea. Permanent bait stations are maintained on the island to prevent reinvasion (K. Varnham, pers. comm.). The possible occurance of Capra hircus, Mus musculus and Herpestus aurupunctatus (the latter having been reported from Green Island before) was carefully investigated but no proof was found in the end. Thus the project finally only eradicated around two thousand rats from the island. An Oct 2001 report by Karen Varnham on a follow-up visit is available (G. Meier, pers. comm.).
    Harakeke Is.
    An attempt was made in 1992 to eradicate Rattus rattus from Harakeke Island (12 ha), led by D. Taylor, but was not completed (D. Taylor, pers. comm.).
    Hardy Is.
    Rattus rattus was eradicated from Hardy Island (2.63 ha) between 1999 and 2002 in a programme undertaken by PNR Martinique and INRA (led by Michel Pascal). The eradication was achieved using hand broadcast of traps and bromadiolone (50ppm) on a 30 x 30m grid over three years (Pascal et al.. 2004; Pascal, pers. comm.).
    Haulashore Is.
    Haulashore Island (6 ha) had a population of approximately 300 ship rats in 1991. An eradication programme was carried out using Talon WB 50 (brodifacoum) baits distributed in bait stations in a programme led by R. Taylor and B. Thomas (Thomas and Taylor, 2002; Taylor, pers. comm., D. Veitch, pers. comm.). Eradication was achieved over 90 days. The results of this eradication suggest that ship rats, like Norway rats (Rattus norvegicus), are susceptible to 'peer pressure', in that they will follow one another to food sources (Thomas and Taylor, 2002).

    Rats were confirmed to have reinvaded in 2005, although it is thought that the actual reinvasion occurred between 1998 and 2002. This is likely to have occurred due to the small water gap required to be crossed from the mainland (Russell, 2005).

    Houtman Abrolhos Is. (Western Australian Islands)
    Ship rats were eradicated from the Houtman Abrolhos Islands in 1993, using oats vacuum-impregnated with pindone on a 25 m grid.
    Ile du Chateau (sub-Antarctic) (Kerguelen Archipelago (sub-Antarctic))
    An attempt has been made to eradicate Rattus rattus from Ile du Chateau (250 ha) using brodifacoum (led by T. Micol) (J.L. Chapius, pers. comm.).
    Îlle Aux Aigrettes
    Rattus rattus was eradicated from Ille aux Aigrettes in 1987, in a programme undertaken by the Jersey Trust and led by Don Merton. The eradication was achieved using one application of brodifacoum (20 ppm) at a rate of 20kg/ha (B. Simmons, pers. comm.; Merton, 1987; D. Merton, pers. comm.). Endemic pink pigeons (Columba mayeri) and Mauritian kestrels (Falco punctatus) have since been reintroduced (K. Varnham, pers. comm. 2002).
    Isola dei Topi
    An attempt to eradicate Rattus rattus from Isola dei Topi (10 ha) was carried out in 2000 (Perfetti and Sposimo, 2001; Perfetti et al.. 2004).
    Isola La Scola
    An attempt to eradicate Rattus rattus from Isola La Scola (2 ha) was carried out in 2001 (Perfetti and Sposimo, 2001; Perfetti et al.. 2006).
    Isole Legemini
    An attempt to eradicate Rattus rattus from Isole Legemini (10 ha) was carried out in 1999 and 2000 (Perfetti and Sposimo, 2001; Perfetti et al.. 2001; 2002).
    Isolotto d'Ercole
    An attempt to eradicate Rattus rattus from Isolotto d'Ercole (10 ha) was carried out in 2000 (Perfetti and Sposimo, 2001; Perfetti et al.. 2005).
    Juan de Nova Is. (Îles Éparses (Scattered Islands)) français 
    Several actions were begun in 2007, among them a continuation of the rehabilitation of Juan de Nova with the eradication of cat populations (Felis catus) and Rattus rattus. The remoteness of these islands, their limited size and the lack of civilian populations, make them remarkable "study" sites for actions to control introduced invasive animal populations.
    Kauwahaia Is.
    Rattus rattus was eradicated from Kauwahaia Island in 1989 (in a programme led by G. Taylor) (Veitch and Bell, 1990). Rats were found to have reinvaded during the 1990s (Taylor and Cameron, 1990).
    Kayangel Is.
    A feasibility study was planned for June 2006 as part of a PII (Pacific Invasives Initiative) project, which should lead to a management and eradication plans. Target species for eradication include Norway rats (Rattus norvegicus), ship rats (Rattus rattus), cats (Felis catus) and mice (Mus musculus).
    Koi Is. (North Island)
    Rattus rattus was eradicated from Koi Island in 1996, in a programme undertaken by the University of Auckland (led by M. Lee). The eradication was achieved using trapping and hand broadcast of brodifacoum over a six month period. Talon 50WB bait was left in plastic bags over the island to help prevent reinvasion of the island (Lee, 1999; J. Russell, pers. comm.).
    Lacepede Is. (Western Australian Islands)
    Rattus rattus was eradicated from Middle Lacepede (42 ha) in 1996. The eradication was achieved using pindone bait stations on a 25 x 25m grid, over a one year period (R.I.T. Prince, pers. comm.).
    Lavezzu Islets
    Rattus rattus was eradicated from Lavezzu Island and 16 islets (Tome, 110 ha) in 2000, in a programme undertaken by INRA and Agence Envir. Corse (led by Michel Pascal). The eradication was achieved using trapping over twelve days, and hand broadcast of bromadiolone (50ppm) over 18 days, on a 30 x 34m grid (M. Pascal, pers. comm.).
    Little Cayman
    Environmental Health Section of the Government maintains a rodent control program (Morgan, 1994 in Varnham, 2006) in populated areas only.
    Little Rat Is. (Bay of Islands)
    Rattus rattus was eradicated from Little Rat Island (1 ha) between 1992 and 1997. The eradication was achieved using trapping, and the programme was led by D. Taylor (Shaw, 1997).
    Lobos Is.
    Rattus rattus was eradicated from Lobos Island in 2002, in a programme undertaken by the Charles Darwin Foundation and the Galapagos National Park Service. The eradication was achieved using traps and brodifacoum (27ppm) bait stations on a 30 x 30m grid over a one year period (V. Carrion, pers. comm.; K. Campbell, pers. comm.).
    Lobster Is.
    Rattus rattus was eradicated from Lobster Island in 1998, in a programme undertaken by the Antiguan Racer Conservation Project (led by K. Varnham). The eradication was achieved using brodifacoum (50ppm) bait stations on a 10 x 10m grid over a three week period. Permanent bait stations are now in place around the island, and are checked regularly to prevent reinvasion occurring (K. Varnham, pers. comm.).
    Lord Howe Is.
    Ship rats are currently controlled by poisoning in some areas on Lord Howe Island.
    Lundy Is.
    Rattus rattus was eradicated from Lundy Island in 2004, in a programme undertaken by the National Trust, RSPB, English Nature and Wildlife Management International Ltd (led by Biz Bell). The eradication was achieved using difenacoum (50ppm) bait stations on a 50 x 50m grid over a one year period (K. Varnham, pers. comm.).
    Malta
    Eradication of rats (Rattus rattus and R. norvegicus) is one of a series of actions being undertaken by the EU LIFE Yelkouan Shearwater Project. The overall aim of the project is to increase breeding pairs from 1500 to 2000 pairs nationally, and from 500 pairs to 700 pairs at Rdum tal-Madonna Special Protected area (75.3 hectares) (BirdLife Malta, undated).
    Marielas Grande Is. (Marielas islets)
    An attempt to eradicate Rattus rattus from Marielas Grande was carried out in 2004, in a programme undertaken by the Charles Darwin Foundation and Galapagos National Park Service. The eradication attempt used brodifacoum (27ppm) bait stations on a 25 x 25m grid over a one year period. Eradication is yet to be confirmed (V. Carrion, pers. comm.; K. Campbell, pers. comm.).
    Mauritius
    Control of rats has occurred concurrently with that of mongooses (Herpestes javanicus) in the National Park in south-west Mauritius. In Bel Ombre this ceased after two years.
    Mayor (Tuhua) Is.
    Rattus rattus was eradicated from Mayor Island (Tuhua, 1277 ha) in 2000. The eradication was achieved using an aerial application of brodifacoum (Williams et al.. 2002; www.pestoff.co..nz; D. Veitch, pers. comm.).
    Middle Is.
    Rattus rattus was eradicated from Middle Island (350 ha) in 1991. The eradication was achieved using pindone bait stations on a 25 x 25m grid over a one year period (Morris, 2002). Middle Island is home to the threatened golden bandicoot (Isoodon auratus), therefore it was necessary to construct a bait station which excluded native species (Burbridge and Morris, 2002).
    Midway Islands
    Rattus rattus was eradicated from Midway Islands, using trapping and either brodifacoum or bromethalin. The removal of rats has had a positive effect for native plant species such as naupaka (Scaevola sericea) and nohu (Tribulus istoides). Rats had earlier been observed chewing on apical and lateral buds of the naupaka (Starr and Martz, 1999). Cargo and boat traffic are strictly regulated on Midway Atoll to prevent accidental reintroduction of rats. Poison bait is set out on the pier as a secondary precaution (A. Bell, USFWS).
    Mokopuna (Leper) Is.
    Rattus rattus was eradicated from Mokopuna (Leper) Island (1 ha) between 1988 and 1990, in a programme led by S. Butcher (Veitch and Bell, 1990; D. Veitch, pers. comm.).
    Monito Is.
    An eradication programme was initiated in 1992, using bromadiolone. However, in April 1993, the United States Fish and Wildlife Service (USFWS) stopped the programme due to concern about the possibility of poisoning the Monito Island gecko. The programme continued using snap-trapping only. In 1998, the second eradication campaign began, using the rodenticide with the approval of USFWS (brodifacoum). The risk of poisoning non-target species such as the endemic yellow-shouldered blackbird (Agelaius xanthomus) and the zenaida dove (Zenaida aurita) was reduced by the use of baiting stations. No rats have been detected since 1999. Monitoring continues using chewing sticks. The probabity of reinfestation is low due to the isolation and ruggedness of Monito Island.
    Mont Panié
    A three year feasibility project initiated in 2003 by pest control specialists from the Invasive Species Specialist Group (ISSG, IUCN) has focussed on the 5000 hectare Mont Panié Botanical Reserve and has investigated the control of pest mammals in north-eastern New Caledonia. In 2004 the project control techniques focusing on feral pigs and rats were investigated. During September and October 2005 an intensive rat trapping and field trial programme was conducted at a 100 hectare site at Thoven and local people were trained in rat trapping and monitoring. Both the ship rat (Rattus rattus) and the Pacific rat (Rattus exulans) were controlled at target levels. Results from the investigations and trials suggest there is potential to effectively control a range of pest mammals on Mont Panié.
    Montebello Islands
    An eradication programme using bran pellets with brodifacoum was initiated in 1996. The presence of granivorous birds bar-shouldered dove (see Geopelia humeralis in IUCN Red List of Threatened Species) and brown quail (see Coturnix ypsilophora in IUCN Red List of Threatened Species) required bait stations had to be developed to exclude these species but still allowed access by rats. This was achieved using a plastic bottle with two 43 mm holes cut in its sides, placed over a 50 m grid. Eradication was achieved on all islands except Hermite and two adjacent islands, where rats were detected in 1999. An initial helicopter baiting in 1999 did not result in eradication, probably because of logistical and technical problems. A helicopter baiting of all western islands took place in 2001. Monitoring up to 2005 suggest that eradication has been achieved. Two threatened mammals have been successfully introduced to the archipelago: mala (see Lagorchestes hirsutus in IUCN Red List of Threatened Species undescribed mainland subspecies) was introduced to Trimouille Island (520 ha) in 1999 and djoongari Shark Bay mouse, (see Pseudomys fieldi in IUCN Red List of Threatened Species) was introduced to North West Island (135 ha) in 2000). Proposals are being developed to reintroduce 3 species of mammals and two species of birds to Hermite Island, and further introductions of mainland highly threatened mammals are being considered.
    Montserrat
    Experimental rat control is ongoing at a small sample of Montserrat oriole nesting sites in the Centre Hills. There are plans to revive rat control in agricultural areas (Hilton, 2004 in Varnham, 2006).
    Mosquera Is.
    Rattus rattus has been eradicated from Mosquera Island, in a programme undertaken by the Charles Darwin Foundation and Galapagos National Park Service. The eradication was achieved using hand broadcast of brodifacoum (27 ppm) and 1080 (F. Cruz, pers. comm.; K. Campbell, pers. comm.).
    Moturako Is. (North Island)
    An attempt was made to eradicate Rattus rattus from Moturako Island in 1990, but was not completed (G. Taylor, pers. comm.; D. Veitch, pers. comm.).
    Moturoa Is.
    Rattus rattus was eradicated from Moturoa Island (157 ha) in 1994. Constant reinvasions occur, and individuals are trapped or poisoned by various landowners (J. Russell, pers. comm.).
    Motutapere Is. (Cavalli Islands)
    Rattus rattus was eradicated from Motutapere Island in 1994 (P. Thomson, pers. comm.), but reinvaded in 2003. A further poison drop to eradicate the reinvaded rats is planned for July 2005 (MacKay and Russell, 2005).
    Mouse Is. (Bay of Islands)
    Rattus rattus was eradicated from Mouse Island (1 ha) between 1992 and 1993, in a programme led by D. Taylor (Shaw, 1997; D. Veitch, pers. comm.; J. Russell, pers. comm.).
    New Zealand
    Mainland rodent control strategies usually set targets of low R. rattus densities over bird breeding seasons, and integrate with other pest control. Techniques include a range of pesticides and kill traps (Broome, 2004). Active control of ship rats over large tracts of forest on the mainland increased during the 1990s, in part due to evidence that rat control was of benefit to declining native populations (Innes, 2001). They have been controlled to low levels in up to 4000 ha forest blocks by both aerial and ground poisoning, and by trapping. In addition, ship rats have been killed as a by-product of the aerial 1080 operations directed at possums over the past five decades. Ship rats and possums are now frequently co-targeted in control programmes (Innes, 2001). The Department of Conservation aims to reduce its use of brodifacoum on the mainland from 1999, due to concerns about its persistence in the environment (Innes, 2001).
    Towns and Broome (2003) outline the history of rat eradications in New Zealand. Innes et al (1995) provides information on the chemical control of the ship rat on mainland New Zealand.
    North Double Is.
    An eradication attempt was made in 1983, using pindalone oats placed in bait stations. No signs of rats have been found during visits in 1991 and 2000.
    North Is. (Seychelles)
    An attempt was made to eradicate Rattus rattus from North Island in 2003, but was not successful. The attempt was undertaken by the island owner (led by G. Climo), and involved three aerial applications of brodifacoum (20 ppm) (D. Merton, pers. comm.).
    Northern Sporades National Marine Park (Northern Sporades Is.)
    Eradication of black rats on the three islets commenced during March 2005. 150 kg of the anticoagulant rodenticide Brodifacoum-based BRODIRAC was hand broadcast at bait stations on the islets in March 2005, before the falcons had returned from their winter quarters in Africa. More than 18 months later, there is no evidence rats survive on the 15 ha Lagofytonisia islets which have been declared rat-free. The project was carried out as part of an EU-LIFE project to improve conservation measures for the Eleonora’s Falcon
    A second rat eradication trial is now underway on the 4.5 ha Kastronisia islets in the Northern Sporades, which host up to 24 pairs of Eleonora’s Falcon, and suitable eradication sites across hundreds of Greeks islands in the whole Aegean are being identified and prioritised for future rat-removal (BirdLife International, 2007).
    Nukulaelae Is.
    Mongooses were introduced about 1950 (from Fiji) in an attempt to control rats, but they died out.
    Opakau Is. (North Island)
    An attempt was made to eradicate Rattus rattus from Opakau Island (4 ha) in 1990, but was not completed (G. Taylor, pers. comm.; D. Veitch, pers. comm.).
    Oyster Is.
    An attempt was made to eradicate Rattus rattus from Oyster Island (1 ha) in 1990, but was not completed (G. Taylor, pers. comm.; D. Veitch, pers. comm.).
    Pasco Is.
    Rattus rattus was eradicated from Pasco Island (2 ha) in 1985. The eradication was achieved using pindone bait stations on a 25 x 25m grid over a one year period (Morris, 1989).
    Pearl Is. (Stewart Is.)
    A rat eradication operation commenced on Pearl Island (512 ha) in 2005 (B. Beaven, pers. comm.).
    Perce Is.
    Rattus rattus was eradicated from Perce Island (0.54 ha) in 1999, in a programme undertaken by PNR Martinique and INRA (led by Michel Pascal). The eradication was achieved using hand broadcast of bromadiolone (50ppm) over 18 days on a 30 x 35m grid, and trapping over twelve days (Pascal et al.. 2004; M. Pascal, pers. comm.).
    Phil's Hat Is. (Bay of Islands)
    Rattus rattus was eradicated from Phil's Hat between 1992 and 1993, in a programme led by D. Taylor (Shaw, 1997; D. Veitch, pers. comm.).
    Pinzon Is.
    An attempt to eradicate Rattus rattus from Pinzon Island was carried out in 1987, but was not successful. It was undertaken by the Charles Darwin Foundation and the Galapagos National Park Service. The methods used included coumatetralyl bait stations on a 25 x 25 m grid, hand broadcast of brodifacoum (27ppm), and 1080, over a 45 day period (F. Cruz, pers. comm.; K. Campbell, pers. comm.).
    Pitt Is.
    Rattus rattus was eradicated from Pitt Island in 1989, in a programme undertaken by the Charles Darwin Foundation and the Galapagos National Park Service. The eradication was achieved using hand broadcast of 1080 and trapping (F. Cruz, pers. comm.; Munoz, 1996; K. Campbell, pers. comm.).
    Poirier Is.
    Rattus rattus was eradicated from Poirier Island (2.1 ha) in a programme undertaken between 1999 and 2002, carried out by PNR Martinique and INRA (led by Michel Pascal). The eradication was achieved using hand broadcast of bromadiolone (50ppm) and trapping on a 30 x 37m grid (Pascal et al.. 2004; M. Pascal, pers. comm.).
    Pribilof Islands
    A prevention programme was set up in 1993 to prevent the accidental introduction of rats. This consists of trap and poison stations, community education, outreach to vessels, local shipwreck response capabilities, and regulations. Several rats have been killed on the St Paul docks but there is no evidence of establishment. Snap traps appear to be more effective than poison, but cause minor loss to non-target species.
    Prince Is. (Western Australian Islands)
    Rattus rattus was eradicated from Prince Island (4 ha) in 1983, using pindone bait stations on a 25 x 25m grid over a one year period (Morris, 1989).
    Rabbit Is. (Antigua)
    Rattus rattus was eradicated from Rabbit Island in 1998, in a programme undertaken by the Antiguan Racer Conservation Project (led by K. Varnham). The eradication was achieved using brodifacoum (50ppm) bait stations on a 10 x 10m grid over a three week period. Permanent bait stations are now in place around the island, and are checked regularly to prevent reinvasion occurring (K. Varnham, pers. comm.).
    Rarotonga Is.
    In a review of bird conservation problems in the South Pacific, commissioned by the South Pacific Regional Environment Programme (SPREP) and the International Council for Bird Preservation (now Birdlife International) in the early 1980s, it was identified that the 'Endangered (EN)' kakerori, or Rarotonga flycatcher (see Pomarea dimidiata in IUCN Red List of Threatened Species) as one of the species most urgently in need of conservation management (Robertson et al. 1994). As a result of a study begun in September 1987, it was confirmed that the conservation status of kakerori was ‘critically endangered’. They also reported to the Cook Islands Conservation Service (now Cook Islands Environment Service) and SPREP, that ship rats (Rattus rattus) were having a detrimental effect on the breeding of kakerori, and that cats (Felis catus) were likely to be predators of recently fledged juveniles and adult birds.

    The draft plan for the recovery of kakerori recommended a cost-effective experimental recovery programme targeting predators of kakerori and scientific study aimed at assessing the effectiveness of this work. A rat poisoning regime to simply ‘sustain’ the population of kakerori, was designed and implemented. Breeding success was significantly better in poisoned areas (0.95 fledglings/breeding territory) than in unpoisoned areas (0.30 fledglings/ breeding territory). Breeding success was similar in areas receiving weekly and fortnightly rat poisoning (0.97 and 0.93 fledglings/territory, respectively), indicating that the latter poisoning regime was adequate to reduce rat densities to a level which allowed most kakerori to nest successfully.

    Yearly accounts of 'The Kakerori Recovery Plan' are available from Robertson and Saul, 2004; Robertson & Saul, 2005; Robertson & Saul, 2006; Robertson & Saul, 2007; and Robertson & Saul 2008.
    Please follow this link to read the Kakerori Recovery Plan: A Conservation / Invasive-Species Management Case Study 2007.

    Rat Is. (New Zealand) (Bay of Islands)
    Rattus rattus was eradicated from Rat Island (56 ha) in 1993. The eradication was achieved using pindone bait stations on a 25 x 25m grid over a one year period (Burbridge et al.., unpublished).
    Ray Francisco
    An attempt to remove Rattus rattus from Ray Francisco (12 ha) was made in 2000 (Orueta, 2002).
    Rdum tal-Madonna
    Eradication of rats (Rattus rattus and R. norvegicus) is one of a series of actions being undertaken by the EU LIFE Yelkouan Shearwater Project. The overall aim of the project is to increase breeding pairs from 1500 to 2000 pairs nationally, and from 500 pairs to 700 pairs at Rdum tal-Madonna Special Protected area (75.3 hectares) (BirdLife Malta, undated).

    Work on rat control began in December 2006 until March 2007. The aim of the project was to remove rats from the main part of the site and then, using a network of regularly inspected permanent bait stations, detect and destroy any rats moving into the area. Please follow this link Varnham and Meier, 2007 for more details on methods used, results, recommendations and future of the project (Varnham and Meier, 2007).

    Reunion (La Reunion)
    Since 1977, crop growers as well as non growers participate to control campaigns set in place by the grower union FDGDON (Fédération Départementale des Groupements de Défense contre les Organismes Nuisibles ). Rodents are subject to chemical control campaigns once or twice a year depending of the county (in french "communes")
    Saddle Is. (North Island)
    An attempt was made to eradicate Rattus rattus from Saddle Island (2 ha) in 1990, but was not completed (G. Taylor, pers. comm.; D. Veitch, pers. comm.).
    Saint Helena
    Poisoning campaigns were carried out against the black rat in the 1990s to control rats in towns (Ashmole and Ashmole, 2000 in Varnham, 2006).
    Saint-Paul Is. (sub-Antarctic)
    An eradication attempt was made in January 1997, in conjunction with an attempt at eradicating rabbits. A single aerial drop of brodifacoum bait was used in the dry season. Surveys were continued for two years after the bait drop, with no rat signs, and they have been declared eradicated.
    Saint-Paul Is. (sub-Antarctic) français 
    A campaign to eradicate black rats (Rattus rattus) and rabbits (Oryctolagus cuniculus) was conducted in 1997 with co-financing from the French Southern and Antarctic Territories and the European Development Fund. The total eradication of rats was proven over three successive campaigns and eradication of the rabbits was obtained after the second campaign and certified during the next one (Micol et Jouventin, 2002).
    San Jorge East Is.
    Rats were eradicated using rodenticide (diphacinone) in bait stations. Bait stations remained active for one year.
    San Jorge Middle Is.
    Rats were eradicated using rodenticide (brodifacoum) in bait stations. Bait stations remained active for one year.
    San Jorge West Is.
    Rats were eradicated using rodenticide (cholecalciferol) in bait stations. Bait stations remained active for one year.
    San Roque Is.
    Rats were eradicated using brodifacoum wax blocks in combination with bromethalin gel. Bait stations remained active for one year.
    Sandy Cay
    Rats eradicated from 5 ha Sandy Cay (nr Tortola) in 2002 (Varnham, 2003 in Varnham, 2006).
    Sandy Is. (Western Australian Islands)
    Ship rats were eradicated from the Lacepede Islands in 1986, using oats vacuum-impregnated with pindone on a 25 m grid.
    Sangalaki Is.
    After other options (for example to introduce cats!) had been rejected, InGrip-Consulting recommended a rat-eradication attempt and the islands' further protection as the solution of the problem. The decision to try a complete eradication was made because of the island’s small size, the absence of any endemic, native or threatened rodent species and even any terrestrial mammals at all, the specific extent of the problem the rats pose to this conservation site, the approximate population size the invasive rats had established, the significance of Sangalaki as a unique marine turtle nesting site in the region, the availability of funds, time and motivated personnel to undertake such an operation, including the necessary follow up work, the potential to use such a project as a demonstration project for other places with the same problem in the area, and the support and willingness to act by all potential partners and stakeholders involved. All operational cost were carried by the Turtle Foundation. The project was planned in great detail and began in 2003.
    It was decided to use a commercially available rodenticide, from the group of so called ‘second generation anticoagulants’ – poisons which interrupt the animals Vitamin K production thus hindering the process of natural blood clotting. It is produced in poisoned grains that are mantled by a wax layer for better weather protection and pressed into cube form. The toxin is ‘brodifacoum’ in a concentration of 0.005 mg, which allows a rat to ingest a lethal dose within a single feeding. The trade name of the poison chosen was “Klerat” and is worldwide available from the production company, Syngenta.
    The last living rats were observed on the 14th of July and all bait and bait station were withdrawn on the 26th of July 2003). The total amount of bait used reached around 55 kg, (equivalent to 4,15 kg/ha). Live trapping with Tomahawk collapsible live-traps (Type TLT no. 202 - squirrel size), was undertaken for several days to detect any potentially surviving rat. Highly attractive bait (fish, shrimps, chicken, fruits, peanut butter, toasted bread and cookies) was used and traps set on carefully chosen localities, spread over the whole island, but in totally 444 trapping hours between the 19th of July and 26th of July 2003 no rat was caught. The same live-trapping procedure was undertaken on the 2nd and 3 rd July 2003 and resulted in the catch of 8 animals (including one female with juvenile) in only 7 trapping hours. Until proven different Sangalaki Island was therefore declared temporarily rat free at Guntram Meier’s departure on the 28th of July 2003. A full report is available (InGrip-Report).
    A visit by Guntram G. Meier in January 2004 confirmed that no rats survived the eradication. As no further losses of turtle eggs or hatchlings due to rat predation were recorded, the eradication of this invasive alien species on the island can be considered a complete success and contributed to the ongoing marine turtle protection work on the island. Plans for related work on neighboring islets are currently under discussion (Marine Turtle Newsletter No. 106, 2004). While the rat eradication project was designed for the well-being of marine turtles, it also seems to have benefited megapodes such as Megapodius cumingii on the island (Megapode Newsletter 2004).
    Somes (Matiu) Is.
    Rattus rattus was eradicated from Somes (Matiu) Island (32 ha) in 1988, in a programme undertaken by the Department of Conservation (led by S. Butcher). The eradication was achieved using brodifacoum (Veitch and Bell, 1990; D. Veitch, pers. comm.; J. Russell, pers. comm.).
    South Double Is.
    An eradication attempt was made in 1983, using pindalone oats placed in bait stations. No signs of rats have been found during visits in 1991 and 2000.
    Stewart Is.
    Hickson et al. (1986) describes the use of rat poison at four places near Port Pegasus in southern Stewart Island. These places are visited by fishing boats en route to the Snares Islands, an internationally significant, rodent-free nature reserve in the subantarctic. Controlling rats in remote anchorages is expensive and logistically difficult, so it is important to determine whether or not poisoning significantly reduces the probability of rats boarding boats and how resources should best be deployed.

    Poison was used at remote anchorages of southern Stewart Island in spring and summer of 1984/85 to reduce the likelihood of ship rats (Rattus rattus), Norway rats (R. norvegicus) and kiore (R. exulans) boarding fishing boats heading for the Snares Islands. Poison baits were removed at successively slower rates, probably because poisoning had reduced rat numbers. The effectiveness of poisoning was tested by (i) live-capturing and tracking marked rats at a simulated anchorage near Halfmoon Bay, (ii) poisoning there as in southern Stewart Island, and (Hi) monitoring the survival and responses of the marked population. Population density approximated 2.0-2.5 ship rats per hectare before poisoning. The minimum monthly home range of ship rats averaged 0.54 ha (mean range length 142 m), which is much larger than previously recorded for ship rats in New Zealand. Neither Norway rats nor ship rats were restricted to the shoreline or along creeks. Poisoning caused a 93% reduction in an index of rat numbers in a 0.69 ha poisoning zone over 16 days, and a 76% reduction over the larger 10.4 ha effective trapping area including the poison zone. Poisoning reduces the risk of rats boarding boats, and can protect endangered plants and animals on infested islands (Summary from Hickson et al. 1986).

    Tawhitinui Is.
    Tawhitinui Island (21 ha) was used to trial the eradication of ship rats in 1983. Bait stations filled with Talon WB 50 (brodifacoum) bait were used. Follow-up monitoring in 1984 detected no signs of rats. In 2000, it was found that ship rats had reinvaded Tawhitinui Island (Russell and MacKay, 2005).
    Titi Is.
    Rattus rattus was eradicated from Titi Island in 1970, in a programme undertaken by the New Zealand Wildlife Service (led by B. Bell and D. Merton). The eradication was achieved using two hand broadcast applications of warfarin, at a cost of $100 (Gaze, 1983; Veitch and Bell, 1990; D. Veitch, pers. comm.; D. Merton, pers. comm.; J. Russell, pers. comm.).
    Tristan da Cunha Is. (sub-Antarctic)
    A feasibility study for eradication of rats from Tristan da Cunha has been prepared, along with a draft operational plan. If attempted, a rat eradication from Tristan would be expected to be challenging due to the presence of an established human population, along with the presence of livestock on the island. However, the longer that rats remain on Tristan, the greater the risk that they will be inadvertently introduced to the currently rat-free islands of Nightingale and Inaccessible with devastating effects.
    Wenderholm Regional Park
    Intensive control of alien species commenced at Wenderholm in 1992, when annual rodent poisoning began from spring to late summer, alternating between Talon 50 WB pellets (brodifacoum) and Storm Rodenticide (Flocoumafen), to avoid selection for toxin resistance. Initially, drainpipe bait stations were used, but in 1999 these were replaced with Philproof bait stations to reduce bait wastage, and Pestoff Rodent Blocks were used (brodifacoum) as the bait. Rat numbers have been reduced to very low levels, and there is no evidence of predation on translocated robin (Petroica australis) nests. There is some concern about the residual effects of second-generation anticoagulants, and future poisoning operations may require a more environmentally acceptable toxin.
    West Is. (Western Australian Islands)
    Ship rats were eradicated from the Lacepede Islands in 1986, using oats vacuum-impregnated with pindone on a 25 m grid.


         Management Resources/Links

    2. Angel, A. & Cooper, J. 2006. A Review of the Impacts of Introduced Rodents on the Islands of Tristan da Cunha and Gough. RSPB Research Report No. 17. Royal Society for the Protection of Birds, Sandy,United Kingdom.
    5. Baker-Gabb D. 2004. National Recovery Plan for the Norfolk Island Scarlet Robin Petroica multicolor multicolor and the Norfolk Island Golden Whistler Pachycephala pectoralis xanthroprocta. Commonwealth of Australia, Canberra.
    12. Brown, D. 2006a. Preliminary Operational Plan For Rat and Mouse Eradication from Tristan da Cunha. Unpublished report to RSPB.
    13. Brown, D. 2006b. A Feasibility Study for the Eradication of Rats and Mice from Tristan da Cunha. Unpublished report to RSPB.
    15. Burbidge, A.A., 2004. Montebello Renewal: Western Shield review—February 2003. Conservation Science Western Australia 5(2), 194-201.
    17. Chagos Island Restoration Project 2006 (CERP). Fauna and Flora International.
    18. Christie, J.E., D.J. Brown, I. Westbrooke and E.C. Murphy., 2009. Environmental predictors of stoat (Mustela erminea) and ship rat (Rattus rattus) capture success. DOC Research & Development Series 305. Published by Publishing Team Department of Conservation PO Box 10420, The Terrace Wellington 6143, New Zealand
            Summary: Abstract: The association between capture success of stoats (Mustela erminea) and ship rats (Rattus rattus) and landscape-scale environmental predictors was explored using trapping data from three stoat control areas located in podocarp/broadleaved forest in New Zealand. Stoat capture success was higher at trap sites where a rat was also captured at the same trap or a stoat was captured at a neighbouring trap. Drier trap sites with good soil drainage and increased proximity to the operational trapping boundary were also associated with increased stoat capture. Rat capture success was higher at trap sites where a rat had been captured at a neighbouring trap, and at trap sites that were on steeper ground, more easterly facing and within forest habitat. Trap sites with generally poor soil conditions, i.e. sites with lower soil calcium levels and wetter sites with poor drainage, and increasing distance from the forest edge were also associated with increased rat capture. There were highly variable relationships between rat and stoat capture and landscape-scale environmental predictors between the three stoat control areas. This could be due to differing topography, but also to the highly correlated nature of many of the topographic, climate and habitat predictors. Further research specifically designed to separate these effects should focus on the variables identified as common between all stoat control areas in this study. Additional investigations of whether rats captured in double trap sets act as additional bait for stoats would have practical benefits for stoat control areas. The variability of the results emphasises the importance of ensuring that traps are abundant and widespread in stoat control operations.
    20. Cunningham, D.M. and Moors, P.J., 1993. Guide To The Identification And Collection Of New Zealand Rodents. Department of Conservation, NZ.
            Summary: A Guide To The Identification And Collection Of New Zealand Rodents, information on trapping methods.
    22. Doty, R. E. 1945. Rat control on Hawaiian sugar cane plantations. Hawaiian Planters Record 49(2): 71–241.
    23. Gerber, G. 1997. Nesting Behavior of the Little Cayman rock iguana, Cyclura nubila caymanensis. Joint Annual Meeting, American Society of Ichthyologists and Herpetologists/Herpetologists League/Society for the Study of Amphibians and Reptiles. University of Washington, Seattle, U.S.A.
    24. Innes, J., Hay, R., Flux, I., Bradfield, P., Speed, H. and Jansen, P. 1999. Successful recovery of North Island kokako Callaeas cinerea wilsoni populations, by adaptive management. Biological conservation 87: 201-214.
    26. IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4.
            Summary: The IUCN Red List of Threatened Species provides taxonomic, conservation status and distribution information on taxa that have been globally evaluated using the IUCN Red List Categories and Criteria. This system is designed to determine the relative risk of extinction, and the main purpose of the IUCN Red List is to catalogue and highlight those taxa that are facing a higher risk of global extinction (i.e. those listed as Critically Endangered, Endangered and Vulnerable). The IUCN Red List also includes information on taxa that are categorized as Extinct or Extinct in the Wild; on taxa that cannot be evaluated because of insufficient information (i.e. are Data Deficient); and on taxa that are either close to meeting the threatened thresholds or that would be threatened were it not for an ongoing taxon-specific conservation programme (i.e. are Near Threatened).
    Available from: http://www.iucnredlist.org/ [Accessed 25 May 2011]
    27. IUCN South-Eastern Europen e-Bulletin December 2006. Issue 11: Rats exterminated in important colony of Eleonora’s falcon
            Summary: The IUCN Red List of Threatened Species provides taxonomic, conservation status and distribution information on taxa that have been globally evaluated using the IUCN Red List Categories and Criteria. This system is designed to determine the relative risk of extinction, and the main purpose of the IUCN Red List is to catalogue and highlight those taxa that are facing a higher risk of global extinction (i.e. those listed as Critically Endangered, Endangered and Vulnerable). The IUCN Red List also includes information on taxa that are categorized as Extinct or Extinct in the Wild; on taxa that cannot be evaluated because of insufficient information (i.e. are Data Deficient); and on taxa that are either close to meeting the threatened thresholds or that would be threatened were it not for an ongoing taxon-specific conservation programme (i.e. are Near Threatened).
    Available from: http://www.iucnredlist.org/ [Accessed 25 May 2011]
    28. IUCN/SSC Invasive Species Specialist Group (ISSG)., 2010. A Compilation of Information Sources for Conservation Managers.
            Summary: This compilation of information sources can be sorted on keywords for example: Baits & Lures, Non Target Species, Eradication, Monitoring, Risk Assessment, Weeds, Herbicides etc. This compilation is at present in Excel format, this will be web-enabled as a searchable database shortly. This version of the database has been developed by the IUCN SSC ISSG as part of an Overseas Territories Environmental Programme funded project XOT603 in partnership with the Cayman Islands Government - Department of Environment. The compilation is a work under progress, the ISSG will manage, maintain and enhance the database with current and newly published information, reports, journal articles etc.
    30. Johnson, M. S. 1945. Rodent control on Midway Islands. US Naval Medical Bulletin 45: 384–398.
    31. Lorvelec, O., Delloue, X., Pascal, M., & mege, S. 2004. Impacts des mammiferes allochtones sur quelques especes autochtones de l'Isle Fajou (Reserve Naturelle du Grand Cul-de-sac Marin, Guadeloupe), etablis a l'issue d'une tentative d'eradication. Revue D'Ecologie - La Terre et La Vie 59(1-2): 293-307.
            Summary: French language. Information about impacts, eradication methodology, results and discussion in French.
    34. Marine Turtle Newsletter No. 106, 2004
            Summary: Describes the rat eradication on Sangalaki Is. as part of a green turtle (Chelonia mydas) conservation programme.
    Available from: http://www.seaturtle.org/mtn/archives/mtn106/ [Accessed 19 February 2008]
    36. Megapode Newsletter Vol. 18, nr. 1 October 2004. BirdLife/WPA/SSC Megapode Specialist Group
            Summary: Describes observations and conservation through rat eradication.
    41. Moors, P. J., Atkinson, I. A. E. and Sherley, G. H. 1992. Reducing the rat threat to island birds. Bird Conservation International 2: 93–114.
    47. Recher, H. F. and Clark, S. S. 1974. A biological survey of Lord Howe Island with recommendations for conservation of the island’s wildlife. Biological Conservation 6: 263–273.
    48. Robertson, H. A. Hay, J. R., Saul, E. K and McCormack, G.V. 1994. Recovery of the Kakerori: An Endangered Forest Bird of the Cook Islands, Conservation Biology 8 (4): 1078-1086.
    56. Sommer, E. 2006. Trip report. Unpublished report to RSPB.

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ISSG Landcare Research NBII IUCN University of Auckland