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This web site is devoted to DLNR's efforts to control invasive species in Hawai`i. It is designed to provide insight about specific threats to our state's ecosystems and provide information about the department's eradication efforts.

Invasive species - things you can do …

What can you do to protect Hawai`i from invasive species? Plenty! We are all ka poe malama 'aina, people who care for the land and sea. You can help the Department of Land and Natural Resources protect our natural resources by finding out what you can do to keep invasive species from entering Hawai`i, or from spreading if they do get here.

Be informed - Get involved!

Visit the State of Hawai`i websites, learn about invasive species and their impacts, look for opportunities where you can volunteer and check the newspapers that announce opportunities for cleaning beaches, streams, forests, roadsides or parks.

Department of Land and Natural Resources:
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Department of Health:
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Department of Agriculture:
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Report a Pest!

Promptly report sightings of plants and animals that don't belong in Hawai`i (snakes, alligators, parrots, miconia, banana poka, exotic birds, and other plants or animals): 

Department of Agriculture (Pest Hotline on O`ahu) (808) 643-PEST
Department of Land and Natural Resources on O`ahu (808) 587-0164

-During business hours, calls will be routed to the nearest HDOA office on all islands. The existing Pest Hotline (586-PEST) is an Oahu number, answered at the airport office, and neighbor island callers need to dial a prefix (1-808), AND they are charged long distance tolls.

-Calls after hours/on weekend hours or periods of inadequate staffing will be routed to the airport office on Oahu, STILL without toll charges to the caller.


Keep pets at home!

Keep your pets (cats, dogs, rabbits, birds, reptiles, fish, etc.) at home. It is illegal to release any non-native animal without a proper permit. 

Cats and dogs prey on native birds; aquarium plants and fish, if released into streams, pond or lakes, compete with and prey on native plants and wildlife; rabbits released into the wild destroy crops and native vegetation; and escaped or liberated exotic birds carry disease, damage fruit and flower farms and compete with endangered native birds. 

Bring any unwanted pets to the Humane Society. If you or a friend has an illegal animal as a pet, turn it in voluntarily to the Department of Agriculture and receive amnesty.


Lose the limu!

When fishing or boating, wash nets, anchor lines and all equipment well with fresh water and check for algae fragments. Keep your boat hull clean so you are not transferring these organisms from one port to another. 

If you are fishing in an area where there is a lot of alien algae make sure to thoroughly wash your gear in fresh water and check to make sure there are no fragments attached. 

Don't use nets or other fishing gear in areas that have high concentrations of alien algae and then move to a site with none, you are likely to transfer it.


Fight the bite!

Reduce or eliminate all standing water in your yard and remove containers in which water can collect, make sure all windows and doors have screens, and keep all screens repaired.

Weeds, tall grass and shrubbery provide an outdoor home for adult mosquitoes, which may also enter houses through unscreened windows or doors or broken screens. Many kinds of mosquitoes will breed in discarded tires.

Mosquitoes are generally considered only a nuisance, but some can transmit disease, such as Dengue Fever and West Nile Virus. For information on controlling mosquitoes, go to blue ball graphic, link to

Unusual numbers of dead birds can signal a problem - Contact Department of Health - 808-425-2535.


Don't mail a pest!

Mail order wisely and ask friends and relatives not to send you plants or animals through the mail or other delivery systems.

Many catalogs offer plants and animals that become serious pests in Hawai`i. Even the desirable plant, fruit or animal sent through the mail may have other pests growing on it. To avoid problems, check with the state Department of Agriculture to be sure a particular catalog item is allowable in Hawai`i.

Obtain the state import permit required for all animals and microorganisms and many plants. Be sure parcels mailed to you are clearly marked "Contains Living Material: Please Open for Agricultural Inspection" to avoid any delays in delivery.


Watch your step!

Clean your hiking boots, tires, dogs, running shoes and other gear before you enter native forest areas or travel inter-island.

Many alien weeds are carried from one island to the next on muddy boots, hunting and camping gear or farm equipment.

The simple precaution of scrubbing your gear can keep some of our worst pests from spreading to other islands or into the heart of our remaining pristine forests.


Make a declaration!

When returning to Hawai`i, fill out your Department of Agriculture declaration form completely and honestly.

Remember, just because you list the item doesn't mean it will be taken away from you. If necessary, it will be inspected and, if it poses a pest threat, it will be dealt with appropriately.

You are not subject to a penalty if you voluntarily submit these items for inspection. If you try to avoid inspection, the consequences are 1) a $100 - $25,000 fine and/or one year in jail (depending on the violation) or 2) being the person responsible for introducing a new disease or other pest to Hawai`i.


Don't pack a pest!

When returning home after a trip away from Hawai`i (or traveling inter-island,) don't bring plants, fruits, vegetables or illegal animals with you.

Plants, fruits, vegetables, pets and even muddy shoes are great hitchhiking vehicles for diseases, insects and weed seeds, which can easily escape and establish themselves as new pests.

Thoroughly clean boots, camping and other gear before returning home to Hawai`i (or after an inter-island trip.) Insects and seeds can also hitch a ride to Hawai`i on your stuff, including plants and pets.


Protect our farms!

Don't spread crop pests by sharing diseased plants. Ask the Hawai`i Department of Agriculture before sending or carrying plants inter-island.

People giving diseased plants to their friends may spread devastating pests; an act of generosity could be a deadly blow to your friend's garden or farm, and to others around the island.


Go native!

Landscape with native plants or non-pest ornamentals. 

There are many beautiful non-native plants that are tempting to use in landscaping or to sell in garden or flower shops that are terrible pests once they escape into the wild. Seeds and spores from non-native plants in your garden can easily spread and establish themselves in our native forests or farms.

Ask DLNR's Kaulunani program for advise on recommended plants for your particular location:

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Run a tight ship!

When you sail or fly on private craft, keep a clean ship. 

Don't be tempted to bring potted plants, animals or other living material to Hawai`i on your sailboat or private plane. Sand, soil and plant products can be full of pests. Ballast water and dirty hulls can carry foreign algae, jellyfish, mollusks and other potentially harmful species to Hawai`i.

Keep a clean craft and report and show everything you do bring to Hawai`i to the Customs and Agriculture inspectors.


Spread the word!

Share this information with a friend. Protecting Hawai`i from pest invasion depends on what you and other individuals do. Encourage your friends and family to do the right thing.

View the graphic: flower button, link toPDF version (542K PDF) of "Invasive species - things you can do …"


Salvinia molesta

Common Name: giant salvinia; aka: Kariba weed, African pyle, aquarium watermoss, koi kandy


image: Lake Wilson prior to start of Salvinia molesta extraction effort

image;  Lake Wilson after extraction operations had ceased

LAST UPDATE: August 11, 2004 - More than a year after successfully controlling a crippling infestation, Lake Wilson remains almost completely Salvinia-free. DLNR's Division of Aquatic Resources does monthly monitoring of the lake. Presently the only location where a few Salvinia plants still exist is on the South Fork amidst an area of California grass less than one acre in size. This area is completely enclosed by a floating oil boom to prevent any chance of the small plants from escaping, and the California grass which provides cover is being removed with the use of an aquatic harvester.

graphic: flower button, link toLearn more about Salvinia molesta in Lake Wilson and the clean-up effort of 2003

graphic: flower button, link toDLNR homepage
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