Global biodiversity loss is disproportionately rapid on islands, where invasive species are a major driver of extinctions. To inform conservation planning aimed at preventing extinctions, we identify the distribution and biogeographic patterns of highly threatened terrestrial vertebrates (classified by the International Union for Conservation of Nature) and invasive vertebrates on ~465,000 islands worldwide by conducting a comprehensive literature review and interviews with more than 500 experts. We found that 1189 highly threatened vertebrate species (319 amphibians, 282 reptiles, 296 birds, and 292 mammals) breed on 1288 islands. These taxa represent only 5% of Earth's terrestrial vertebrates and 41% of all highly threatened terrestrial vertebrates, which occur in <1% of islands worldwide. Information about invasive vertebrates was available for 1030 islands (80% of islands with highly threatened vertebrates). Invasive vertebrates were absent from 24% of these islands, where biosecurity to prevent invasions is a critical management tool. On the 76% of islands where invasive vertebrates were present, management could benefit 39% of Earths highly threatened vertebrates. Invasive mammals occurred in 97% of these islands, with Rattus as the most common invasive vertebrate (78%; 609 islands). Our results provide an important baseline for identifying islands for invasive species eradication and other island conservation actions that reduce biodiversity loss.
The spread of invasive non-native species presents one of the greatest threats to biodiversity globally: invasive species are the primary driver of biodiversity loss on islands and the second largest everywhere else (CBD ; Millennium Ecosystem Assessment, 2005). Many of the UKs island ecosystems have been damaged by the arrival and establishment of invasive non-native species. Introduced predators have caused particularly catastrophic damage to many species of waders and seabirds, undoubtedly causing numerous extirpations as well as contributing to ongoing declines(Stanbury et al. 2017). Removing invasive vertebrates from islands is an important conservation tool to protect and restore island ecosystems and to prevent further declines and losses of native species. The UK Rodent Eradication Best Practice Toolkit is intended as an advisory resource, providing a systematic approach for planning and implementing rodent eradications and biosecurity in the UK. It provides technical advice on specific methods to be used in the UK, as well as an eradication project management framework which is applicable to projects everywhere. This Best Practice Toolkit has been compiled, and contributed to, by several UK governmental and non-governmental organisations involved in island restoration, these being: Royal Society for the Protection of Birds (RSPB), Animal and Plant Health Agency (APHA), Department for Environment, Food and Rural Affairs (Defra), GB Non-Native Species Secretariat (GB NNSS), Joint Nature Conservation Committee (JNCC), National Trust, National Trust for Scotland, Natural England, Natural Resources Wales (NRW), Scottish Natural Heritage (SNH), Scottish Wildlife Trust (SWT) and the Isles of Scilly Wildlife Trust. The Toolkit has also received input from Wildlife Management International Ltd (WMIL), and draws heavily from the documentation produced by WMIL for various rat eradication projects undertaken in the UK.
The use of the UK Rodent Eradication Best Practice Toolkit aims to give UK organisations and practitioners the ability to embark on invasive rodent management projects with greater confidence of achieving the desired island restoration goals. For more information or to provide feedback on this resource, please contact Sophie Thomas [email protected] .
Although the term biodiversity emerged from the pool of obscure jargon quite a few years ago, it is still enshrouded with significant ambiguity. At one extreme, some people use it as a loose synonym for nature. At the other extreme, some people reduce biodiversity to simplistic parameters, such as the number of species. Conservation organizations, both private and public, must navigate these waters with great care. They need to engage a pulic that loves nature as embodied in beautiful places and charming creatures - elk in a Yellowstone meadow or snow leopards on a Himalayan snowfield - while expounding the values of species and ecosystems that have "swamp," "rat," or "spider" in their titles. A the same time, to undertake their work in a systematic and rigorous manner, conservation organizations need to be able to quantify their goals and accomplishments. Some things are easy to measure, such as the areas of new reserves, but biodiversity writ large is not one of them.
Situated between Fiji to the west and Samoa to the northeast, the Kingdom of Tonga (referred
to as Tonga) is comprised of 171 scattered islands of which less than 50 are inhabited. The islands are
mainly composed of limestone formed from uplifted coral. Current critical environmental concerns have
arisen due to deforestation; damage to coral reefs and the introduction and spread of invasive alien
species. Anthropogenic pressure has resulted in extensive modification of all ecosystems on the
limestone islands of this group. Only uninhabited and steep volcanic islands still support large tracts of
forest.
Between the 27th and 29th of October 2015 invasive alien species surveys were conducted as part of
the GEF-PAS invasive alien species project/Samoa to help inform the Aleipata management Plan. As
part of these surveys sticky traps were placed on Nuulua Island to detect the presence of Rattus sp.
The sticky traps were checked after two nights with no evidence of rat presence. These sticky traps
were left for a further 50 nights to increase the chances of detecting rat. As part of this return trip to
Nuulua Island an incidental bird list was compiled and other species of interest (i.e. Yellow Crazy
Ants and Coconut Crabs), were recorded when encountered.
Pacific islands intimately connect land and sea.
Rats, cats, and other invasive species quickly destroy
these links, particularly by predating on native forest
seeds, forest birds, sea birds, and other vital ecosystem
components. Effective management of invasive species is
key to protect terrestrial and marine systems, supporting
their function and increasing their resilience to change.
Late is an isolated and uninhabited island located about 55 km WSW of the island of Vava'u, in the Kingdom of Tonga. Late supports a tropical broad-leaf forest ecosystem, one of the most threatened ecosystem types in the world and one of the best remaining tracts of diverse native forest in Tonga. Owing to its relatively unmodified forest communities, Late is also a global stronghold for two IUCN listed species of bird, one native mammal, and six species of reptile.
Invasive mammal eradications are a proven, effective method of restoring damaged ecosystems and preserving biodiversity. On most tropical oceanic islands indigenous land crabs compete with targeted alien species for bait and interfere with traps and detection devices. Current eradication practices are inherited from successful termperate or subantarctic campaigns, yet we do not possess trued and tried methods for managing land crab interference. This report is the first organized attempt to address what's now commonly referred to as "the land crab problem." Accounts of land crab interference with eradication projects were sourced from an array of eradication practitioners; the resulting information was sorted into major topics and presented in tables, figures, and text. Major topics include: bait application rates, land crab and rat bait consumption, land crab behaviour, land crab interference with bait-stations, land crab deterring bait masks, and toxin exposure risk for non-target species. The summarized information in this report will guide future investigations into the land crab problem.
Anticoagulant rodenticides are an important tool for managing rodents by increasing the chances of success and lowering the resources required. This guide was developed to assist non-specialists in gaining a better understanding of the risks, costs, and benefits of using anticoagulant rodenticides. Everyone has a role to play in ensuring that rodenticides are used responsibly and that the risk of negative impacts to people and the environment is minimised. Failure to do so could result in the loss of support for the use of these useful tools.
