The OTs have many established invasive non-native species, many of which pose threats to agricultural production, wildlife and conservation, and public health. While some species are widespread within a territory, others have a more localised distribution and could be prevented from spreading to vulnerable sites, such as areas or islands of high biodiversity value, or even be eradicated before becoming too problematic. The aim of this work was to answer two questions:

1. What species should be prioritised for eradication from the whole territory?
2. What species established in one part of a territory should be prioritised to stop them spreading to another part of the territory?

Workshops were held in Anguilla and Turks & Caicos Islands (TCI) in January / February 2020. The work involved the development of a framework for the prioritisation of established invasive species for eradication or for control (to reduce the risk of in-territory spread) based on global risk management best practice, using consensus methods similar to those employed for the horizon scanning exercise. For the eradication exercise, species were scored against a range of criteria, with overall feasibility of eradication rated from very high to very low. For the control exercise, species were scored for their ability to arrive, establish and cause impacts on new islands within the territory. All terrestrial non-native species known to be established and potentially invasive in each territory were considered.

For Anguilla, 40 species were assessed for eradication, nine of which were listed as having a high or very high feasibility for OT-wide eradication:

• Jasminum fluminense Brazilian Jasmine
• Wasmannia auropunctata Little Fire Ant
• Plutella xylostella Diamond-Back Moth
• Cryptostegia madagascariensis Madagascar Rubbervine
• Tribulus cistoides False Puncture Vine
• Passer domesticus House Sparrow
• Papilio demoleus Lime Swallowtail
• Diaphorina citri Citrus Psyllid
• Chlorocebus aethiops Vervet Monkey

A total of 308 species / island combinations were assessed for control within Anguilla. The highest threat was from green iguana (Iguana iguana) to Prickly Pear Cays, with other priorities including preventing rodents, some ant species and false puncture-vine (Tribulus cistoides) spreading to Prickly Pear, Dog, Scrub and Sombrero Island.

For TCI, 59 species were assessed for eradication, 13 of which were listed as having a high or very high for OT-wide eradication:

• Iguana iguana Green Iguana
• Washingtonia robusta Mexican Fan Palm
• Solenopsis invicta Fire Ant
• Paratrechina longicornis Longhorn Crazy Ant
• Pheidole megacephala Big-Headed Ant
• Wasmannia auropunctata Little Fire Ant
• Nylanderia fulva Raspberry Crazy Ant
• Pennisetum setaceum Fountain Grass
• Tamarix canariensis Tamarisk
• Tribulus cistoides Dandelion (False puncture Vine)
• Bos taurus Feral Cattle
• Trachemys scripta Red-Eared Slider
• Lawsonia inermis Henna

A total of 297 species / island combinations were assessed for control within TCI. Ambergris Cays were found to be most vulnerable to invasion by the greatest number of species expected to have a high impact if they established, together with some islands from the Leeward Cays and Southern Cays.
Full details are given in the workshop reports:

• Anguilla
• TCI

Guidance documents for the methodology used:

• Overview of scoring method
• Plans for consensus workshop
• Detailed scoring guidance (for external experts)

Presentations on invasive species threats in Anguilla and TCI:

• Anguilla
• TCI

Information note on Anguilla and TCI:

• Anguilla and TCI information sheet