Protecting Paradise from Weeds
Island ecosystems comprise 5% of the earth’s surface yet support up to 50% of the globes endangered plant and animal species. Islands are a storehouse for global biodiversity but are at threat from introduced species. Their limited size and isolation however provides opportunities to secure and conserve species habitats for current and future generations.
Over 700 introduced plants have been recorded on Lord Howe Island, mostly in gardens. Of these, 270 have recognised invasive characteristics. Currently 68 invasive species are declared noxious for Lord Howe Island, out of 156 declared for the whole of New South Wales.
Lord Howe Island Weed Eradication Program
The Lord Howe Island Weed Management Strategy (2006) aims to reduce threats posed by invasive weeds to the island’s natural environment, to human health and agricultural capacity. Approaches to weed management on Lord Howe Island include prevention, early detection, monitoring, control and eradication.
The Lord Howe Island Board has implemented an ambitious program to eradicate at least 25 priority invasive weeds. The LHI Weed Eradication Program Results show that within a short 10 year period between 2004 and 2014, the impact of dense and widespread weed infestations has significantly reduced by 80% across 1,164 hectares of the island. This has been achieved through investment of $6.4 million dollars and over 129,000 hours of grid search method. Helicopter winch and helicopter lance spray programs have been successfully trialled to access weeds on cliffs and rugged terrain.
The Lord Howe Island Board embarked on the ambitious challenge of eradicating 25 priority weeds.
The Lord Howe Island Board ($1.8M) and State and Federal Government ($4.6M) have invested a total of $6.4 million dollars.
Over two million weeds have been removed (seedling to mature weeds) from the island since 2004.
Six invasive weeds eradicated - Cats Claw Vine, Cocos Palm, French Broom, Potato Vine, Tipuana, and Turkey Rhubarb.
Weed populations have reduced by 80% comparing year one to year ten.
Some of the weeds targeted for eradication and numbers of individuals removed over 10 years:
- Cherry Guava Psidium cattleianum IUCN (704,266)
- Ground Asparagus Asparagus aethiopicus WONS (687,404)
- Ochna Ochna serrulata (501,062)
- Bridal Creeper Asparagus asparagoides WONS (110,905)
- Climbing Asparagus Asparagus plumosus WONS (53,804)
- Bitou Bush Chrysanthemoides monilifera WONS (3,459)
New weed threats are being removed before they become widespread:
- Silky Oak Grevillea robusta (271)
- Kahili Ginger Hedychium gardnerianum IUCN (123)
- Singapore Daisy Wedelia trilobata IUCN (94)
- Leaf Cactus Pereskia aculeata (5)
IUCN – Top 100 Global Invasives Database – International Union for the Conservation of Nature (IUCN)
Key Investors Protecting Paradise from Weeds
The outcomes in protecting paradise from weeds has been made possible through the dedication of teams on ground including volunteers, the Friends of Lord Howe Island, with the support from the local community and investment from the following key agencies:
- Caring for our Country (CFOC)
- New South Wales Environmental Trust (NSWET)
- North Coast Local Land Services (NCLLS - formerly NRCMA)
- New South Wales Department of Primary Industries - Weeds Action Plan (WAP)
- Foundation for National Parks (FNP)
- Lord Howe Island Board (LHIB)
Protecting the Investment
To protect the investments and gains made, the importation of invasive plants is prohibited under the LHI Regulations 2014 with details provided in the LHI Plant Importation Strategy 2014. The LHI Biosecurity Strategy 2016 identifies quarantine and surveillance measures to exclude weeds, pathogens and exotic pests from entering Lord Howe Island.
The Next Decade of Weeding
The end point of the weed eradication program was forecast to be achieved over a 30 year period, given adequate resourcing. After 10 years of project delivery and data collection the Lord Howe Island Weed Eradication Program is being reviewed to ensure the program remains adaptable to new technologies, new risks and continues a strong eradication trend. The Lord Howe Island Board is preparing a business case to seek ongoing investment and project partners into the next decade to continue this important island conservation program.
Please see the Publications section for various weed eradication plans, policies and reports.
See the Lord Howe Island User Guide for further information on the weed program and other Lord Howe Island Board conservation initiatives.
A short video on the helicopter lance spray apparatus.