Search the SPREP Catalogue

Rats were eradicated in 20052006 from the islands of Canna and Sanday, Scotland (total area 1,320 ha). Poison bait was laid from December 2005 onwards and the last rat was killed in February 2006. An intensive period of monitoring over the next two years con?rmed that no rats remained on the islands. Seabirds have been monitored on Canna for nearly 50 years and some species have shown good evidence of recovery since the eradication. Other species have not recovered and this may have been due to mortality caused by food shortages or storm events which have been impacting seabirds in the region. These regional changes in pressures affecting the seabird populations make the interpretation of the impacts of the rat eradication programme much more difficult. Atlantic puffins, formerly con?ned to off shore stacks, have recolonised sites on the mainland of Canna and a count of over 2,000 was recorded in 2016. Manx shearwaters, which had ceased nesting in the monitored colony have made a slow recovery to one or two pairs in 2016. Productivity has also increased from a low of 0.2 chicks per nest in the 1990s to 0.74 in 2017. European shags nesting in boulder colonies were most susceptible to rat predation. One such colony has recovered from 45 nests in 2005 to 75 in 2016 and productivity increased from less than 0.7 chicks per nest to an average of 1.6 following eradication. Populations of shags nesting in cliff locations have shown no recovery or have declined. Mew gulls, which nest along the shoreline, have increased from ?ve to over 30 pairs. Other seabirds, such as common guillemots and black-legged kittiwakes, have shown no clear trends and are probably affected by other factors. Rabbit populations have increased on both islands, reaching an estimated 15,500 animals in 2013 that were causing considerable damage through grazing, erosion, and disturbance of archaeological remains. It is unclear whether the increase in rabbit numbers can be attributed to rat eradication. An intensive control programme has brought the rabbit population under control. While some seabirds have responded positively to the rat eradication, the response of some has been slow and others have not responded, probably as a result of regional pressures on their survival. It is important that monitoring of both seabirds and rabbits continues to track the success of this important seabird colony.

Conservation gains and missed opportunities 15 years after rodent eradications in the Seychelles

Accouche, W.

Appoo, J.

Bristol, R.M.

Havemann, C.P.

Millett, J.E.

Retief, T.A.

de Groene, A.

van Dinther, M.A.J.A.

van de Crommenacker, J.

The Seychelles was one of the ?rst tropical island nations to implement island restoration resulting in biodiversity gain. In the 2000s a series of rat eradication attempts was undertaken in the inner Seychelles islands which had mixed results. Three private islands with tourist resorts successfully eradicated rats: Frégate (2000), Denis Island (2003) and North Island (2005). Frégate Island was successful with the ?rst eradication attempt whereas North and Denis Islands were initially unsuccessful, and both required second eradication operations. All three islands have developed conservation programmes including biosecurity, habitat rehabilitation, and species reintroductions, and have integrated nature into the tourism experience. Conservation actions, including rat and other invasive species eradications, on these three islands resulted in the creation of 560 ha of mammalian predator-free land, the reintroduction of seven populations of ?ve globally threatened birds (GTB) and the safeguarding of two existing GTB populations and several reptile and invertebrate species. However, on these and many other islands in the Seychelles, the potential of this conservation model, where island owners implement conservation programmes largely funded by the tourism businesses in collaboration with NGOs (Non-Government Organisations), has not been fully realised. We review the rehabilitation on Frégate, Denis and North Islands from inception to the present, and assess factors that have facilitated the subsequent development of conservation programmes, the presence of receptive businesses and governmental/NGO/donor support and explore limitations on business-led island rehabilitation.

Costs and bene? ts for biodiversity following rat and cat eradication on Te Hauturu-o-Toi/Little Barrier Island

Bell, E.

Campbell, J.

Cassey, P.

Ewen, J.G.

Green, C.

Gri?ths, R.

Joyce, L.

Rayner, M.

Towns, D.

Toy, R.

Veitch, C.R.

Wade, L.

Walle, R.

Considerable bene?ts can be achieved for indigenous biodiversity when invasive vertebrates are removed from islands. In New Zealand, two logistically challenging eradications were undertaken, one to remove cats (Felis catus) and the other Paci?c rats (Rattus exulans) from Te Hauturu-o-Toi/Little Barrier Island (Hauturu). Here we document the short- and long-term impacts of these interventions on the biodiversity of Hauturu. We also assess the extent to which predicted outcomes were re?ected in the measured responses for a wide range of species. Short-term impacts of the eradication program encompassed individual mortality for some native species but no measurable impact to populations. In contrast, at least 11 native vertebrates and one native invertebrate species increased in abundance after rat and cat removal. Fifteen of 34 plant species monitored had signi?cantly more seedlings on Hauturu after rat eradication compared with control islands, indicating future changes in forest composition. Several native species previously not recorded on the island were discovered, including the New Zealand storm petrel (Fregetta maoriana) (formerly considered extinct), the forest ringlet butter?y (Dodonidia helmsi) and eight species of aquatic invertebrate. The chevron skink (Oligosoma homalonotum) has been found in increasing numbers and tuatara (Sphenodon punctatus), raised in captivity on the island, are now re-established and breeding in the wild. These results illustrate an island gradually recovering after a long period of modi?cation. We conclude that more success stories such as Hauturu must be told if we are to allay the publics concerns about such eradication campaigns. And more public support is required if the conservation community is to tackle invasive species at a scale commensurate with the threats they pose.

Practical considerations for monitoring invasive mammal eradication outcomes

Bird, J.P.

Holmes, N.D.

Shaw, J.D.

Varnham, K.

Monitoring provides important evidence to evaluate if invasive mammal eradications on islands achieved conservation goals and to inform future allocation of conservation funds. However, monitoring can be costly, and compete with management actions for resources, so it is important that efforts are targeted. It can be difficult to obtain results of monitoring from previous projects, which puts future projects at a disadvantage when projecting possible conservation outcomes. In this short paper we discuss practical considerations for designing monitoring associated with an eradication programme. We focus on the ecological outcomes of invasive species eradication, as opposed to speci?cally monitoring if an eradication was successful or not. We identify major motivations for undertaking monitoring and present a decision tree intended to improve the efficiency of monitoring by supporting project managers determining when and what to monitor, and how to incorporate monitoring into project planning.

Community-based conservation and recovery of native species on Monuriki Island, Fiji

Brown, J.

Chand, R.

Cranwell, S.

Fisher, R.N.

Harlow, P.

Lovich, K.

Niukula, J.

Rasalato, S.

Seniloli, E.

Thaman, B.

Thomas-Moko, N.

Vadada, J.

The small uninhabited island of Monuriki (40.4 ha) in western Fiji is of national and international conservation concern for its several protected species. Exotic invasive species and a Category 5 cyclone have exacerbated conservation challenges. The cooperation of local, national, and international stakeholders continues to be crucial in restoration of the islands native ?ora and fauna. This summary presents a timeline of restoration efforts and current status of the recovery programme for Monuriki. The critically endangered dry forest habitat of Fiji is only found in a few isolated patches on disparate islands. The Fijian crested iguana (Brachylophus cf. vitiensis) is a critically endangered species restricted to a few small islands in this dry forest zone of western Fiji. The population of crested iguanas on Monuriki Island is the third largest remaining population. Even before iguanas were ?rst documented on the island in the early 1980s, individuals had been removed by local resorts for display purposes, a practice that was previously unregulated. In the late 1990s, the ?rst efforts to conserve and restore Monuriki Island were discussed, but conservation initiatives were not implemented until the development of the Crested Iguana Recovery Plan in 2008. In 2011, domestic goats (Capra hircus) and non-native rats (Rattus exulans) were removed from the island, and 10 pairs of iguanas were brought into captive breeding facilities within Fiji. In 2015, the ?rst 32 captive-bred crested iguanas were released back on Monuriki Island. More than half of these iguanas (N=26) were radio-tracked for 56 days post-release in order to assess survivorship and help provide insights into their short-term movement patterns. Of the 26 iguanas that were tracked, nearly 70% (N=18) were found after 56 days indicating excellent short-term survival. In February 2016, Tropical Cyclone Winston, a Category 5 storm passed through Fiji and devastated some of the tropical dry forest habitat on Monuriki. With sustained winds of up to 230 km/ hr nearly all of the canopy leaves from trees on Monuriki Island were removed and large amounts of debris covered the forest ?oor. Following the cyclone, a brief wildlife survey revealed Monurikis iguana and bird populations were still present. In 2017, the crested iguana captive breeding programme was brought to an end when 16 of the original 20 iguana founders, and an additional 32 captive bred o? spring, were reintroduced onto Monuriki. This was accomplished, in part, due to successful breeding and reestablishment of the remaining wild iguanas on the island. Despite a major storm event, reestablishment likely resulted from reduced egg and hatchling predation by the rats, and excellent habitat recovery after goat removal. Overall these invasive species eradications have proven highly successful for the recovery of the iguanas, wedge-tailed shearwaters (Puffinus paci?cus), and several other non-target species including the banded rail (Gallirallus philippensis) and endangered Fijian peregrine falcon (Falco peregrinus). Furthermore, eradication of non-native species has also helped the recovery of the highly threatened tropical dry forest ecosystem in which these species exist.

Recovery and current status of seabirds on the Baja California Pacific Islands, Mexico, following restoration actions

Aguilar-Vargas, A.

Aguirre-Muñoz, A.

Aztorga-Ornelas, A.

Bedolla-Guzmán, Y.

Bravo-Hernández, E.

Corrales-Sauceda, M.

Cárdenas-Tapia, A.

Fabila-Blanco, A.

Félix-Lizárraga, M.

Hernández-Montoya, J.

Hernández-Ríos, A.

Latofski-Robles, M.

Luna-Mendoza, L.

Méndez-Sánchez, F.

Ortiz-Alcaraz, A.

Rojas-Mayoral, E.

Solís-Carlos, F.

Torres-García, F.

The Baja California Pacifc Islands, Mexico, are globally important breeding sites for 22 seabird species and subspecies. In the past, several populations were extirpated or reduced due to invasive mammals, human disturbance, and contaminants. Over the past two decades, we have removed invasive predators and, for the last decade, we have been implementing a Seabird Restoration Programme on eight groups of islands: Coronado, Todos Santos, San Martín, San Jerónimo, San Benito, Natividad, San Roque, and Asunción. This programme includes monitoring; social attraction techniques; removal of invasive vegetation; reducing human disturbance; and an environmental learning and biosecurity programme. Here, we summarise historical extirpations and recolonisations during the last two decades of restoration actions, and we update the status of breeding species after more than a decade. To date, from 27 historically extirpated populations, 80% have returned since the ?rst eradication in 1995. Social attraction techniques were key in recolonisations of Cassins auklet (Ptychoramphus aleuticus), royal tern (Thalasseus maximus), and elegant tern (T. elegans). A total of 19 species breed on these islands, four more species than a decade ago, including 12 new records. The most abundant seabirds, black-vented shearwater (Puffnus opisthomelas), Cassins auklet, western gull (Larus occidentalis), and Brandts cormorant (Phalacrocorax penicillatus), have shown a remarkable population increase. Current threats include the potential reintroduction of invasive mammals, guano mining, recreational activities, pollution, and commercial ?sheries. To maintain these conservation gains in the long-term it is necessary to continue implementing restoration actions and reinforcing protection on these important natural protected areas.

The recovery of seabird populations on Ramsey Island, Pembrokeshire, Wales, following the 1999/2000 rat eradication

Bell, E.A.

Bell, M.D.

Morgan, G.

Morgan, L.

Ramsey Island, 259 ha, is ca. 1 km off the Pembrokeshire coast, south-west Wales. The eradication of brown rats (Rattus norvegicus) was successfully completed in the winter 1999/2000 using a ground-based bait station operation. The pre-eradication survey using tape playback estimated the Manx shearwater (Puffinus puffinus) population to be 849 pairs. These surveys were repeated in 2007, 2012 and 2016. Each survey showed the Manx shearwater population had increased, reaching 4,796 pairs in 2016 with birds spreading from previously known breeding locations. European storm petrels (Hydrobates pelagicus) were ?rst recorded breeding on Ramsey Island in 2008 with up to 12 pairs in 2016 (a minimum estimate based on accessible survey areas). Other species have also shown improvements to population estimates and range since the rat eradication. This evidence shows that there can be little doubt that the presence of brown rats on Ramsey played a signi?cant role in suppressing breeding numbers and limiting the breeding range of seabirds on the island and the positive results following the successful eradication are now being seen.

Inform Des informations environnementales pour la prise de decision

Le programme Inform offrira aux iles du Pacifique un acces fiable a leurs propres donnees environnementales nationales, ainsi quúne procedure et des conseils sur lútilisation de ces informations.

PROE

2018

Directives De Redaction Dún Rapport Sur Létat De Lénvironnement.

Un rapport national sur létat de lénvironnement fournit des informations sur létat de lénvironment et de la société les tendances et les contraintes observées dans le ppays et dans la mer qui l'entoure.

PROE

2017

Directives de rédaction dún rapport sur létat de lénvironnement|SOE - Report Guidelines