Ministry of Environment, Lands and Agriculture Development

ENVIRONMENT AND CONSERVATION DIVISION

Alien Invasive Species

Wedelia/ trailing daisy, Wedelia trilobata

Brief History

Wedelia or trailing daisy (scientific name: Wedelia trilobata (L.) Hitchc) is an invasive species that is not native to all Pacific Island countries. This species is native to the Caribbean Islands, which is brought to the Fiji Islands as a ground cover. It is an introduced species that has no native competitor, hence is aggressive when escaped and become established in the wild environment. Most importantly, there is also limited literature and research on this particular species, hence scientific knowledge is very limited. This species has been confirmed to be poisonous to both people and animals and people are urged to take precautions when handling wedelia.

Species significance to biological diversity

Despite it uses as good ground cover species, wedelia still has the potential to destroy our limited indigenous flora species, hence dangerous when escaped to the wild environment. If not controlled or managed properly, wedelia are likely to dominate our surrounding environment but most importantly, they would outgrown other indigenous creeping and herbal plants including grasses and sedges that have important places in our culture. Most indigenous plant species have significant ecological services and uses in traditional herbal medicine that play significant roles in traditional health care for many people in Kiribati). These indigenous species provide food, habitats, dispersal mechanisms and predation pressure for other species growing in Kiribati. These ecological roles, services and uses in our traditional culture are likely to disappear if wedelia are left on their own to grow freely in our environment

Infected areas around the Pacific

Some of the Pacific countries that have been already infected by this particular species are Fiji, Niue and Kiribati. Because it is an introduced species (exotic species), wedelia, at this stage, has no local name in Kiribati. The species has been confirmed to exist in Butaritari by staff and team of the National Biodiversity Strategy and Action Plan Project (NBSAP), based at the Environment and Conservation Division (ECD), Ministry of Environment and Social Development. This particular species has been confirmed also to exist in the capital island of South Tarawa and has been escaped to the wild around Bonriki airport. The area infected has been eradicated by Youths of different denominations in South Tarawa who work voluntarily with staff of ECD and is currently under continual surveillance by concerned the staff. Unfortunately, wedelia has been introduced to Nawerewere hospital compound (around the Pharmacy and Operations Theatre departments) as a ground cover. The same species has been confirmed to establish around the catholic compound area (convent) at Teaoraereke.

(Youths from different churches involved in the Wedelia eradication programme during the annual ‘International Day for Biological Diversity’).

What we could do to help eradicate Wedelia?

(Established wedelia around Tebwanimwaneka Primary School compound: South Tarawa)

Because it is highly invasive in nature, people should not be encouraged to transplant this species from infected to non-infected areas. The following are guidelines to ensure that wedelia species do not escape and become establish on the limited atoll environments of Kiribati, particularly on those islands that are already infected:

  • People who wish to plant this species around their front yards as a ground cover are urgently urged to grow this species but need to manage and to ensure that it does not escaped to the wild.
  • It is best to eradicate this species manually in the wild environment. Early detection and report of wedelia seen around the capital island is encouraged and most welcome.
  • Do not throw or disregard wedelia once uprooted. Keep them in piles in a clear space, away from other creeping plants, grasses, etc, and allow them to dry for a day or two. Burn them but do not throw them away at sea or in any other places. If not burned, chances of this species to re-establish and infect new areas are greatly increased.
  • Wash hands and body (if necessary) thoroughly after handling wedelia. Remember, it is a poisonous species and everybody is encouraged to take precautions when handling wedelia.
  • Call Environment and Conservation Division to report any new establishment of wedelia in new areas around the capital island using the following contact:

Biodiversity Section, ECD

Phone: 28-000 or 28-593 or 28-647

(Wedelia in bags, ready to be disposed of. This is a safe way to transport the species around the island if need to be)

1