Invaders: Ants, Snakes, Rats, Mongoose, And That’s Just on Land

Sep 9, 2016

David Moverley is Invasive Species Advisor for the Secretariat of the Pacific Regional Environment Program in Honolulu for the World Conservation Congress. He works with countries through out the pacific to coordinate and expand efforts again invasive alien species. In Hawai'i, we're already overrun with two of the most damaging pests: rats and mongooses.
Credit noe tanigawa

  

Little fire ant bites may be hard to associate with ants at first because the body has a delayed reaction to the bites. They may appear as small bites or as large welts. The ants are known to sting the eyes of dogs, cats, and other pets, who must be treated to avoid blindness.
Credit Hawai'i Ant Lab

  Invasive Alien Species, IAS, are organisms introduced outside their natural range. This week, Hawai'i committed itself to a comprehensive new bio security plan against invasive alien species, but its success depends partly on how vigilant others are.  In 2010, nearly all the world‘s governments agreed to address IAS, but today, only three percent of countries are on track to meet international commitments.  HPR’s Noe Tanigawa reports the Honolulu Challenge issued at the World Conservation Congress hopes to reinvigorate positive efforts.

David Moverley is Invasive Species Advisor for the Secretariat of the Pacific Regional Environment Program, stationed in Samoa.  He was kind of aghast at a cartoon mongoose advertised as a business mascot here.   

“Yeah, I was very surprised to see that on television actually.”

Moverley spent the past four months trying to trap two mongooses who jumped off a ship in Fiji, a major Pacific transit point.  He knows the devastation rats and mongooses have wreaked on Hawai‘i’s native birds.

“Up here in the north, you must be aware of the brown tree snake on Guam and the absolutely disastrous effect it’s had on the native birds there.  So that’s obviously a high risk for you all here in Hawai‘i, and effectively anywhere the US military flies to from Guam.”

Family pets are plagued by little fire ants whose stings can cause blindness, as they did for this cat.
Credit Hawai'i Ant Lab

"Some of the biggest risks at the moment, is the little fire ant.  It’s a huge risk, and it can be very bad on many levels.  Not just for the environment.  It basically drives wildlife from their home.   You can’t really walk through the forest because little fire ants will fall out of the trees onto you.   When you accidentally squash one, it notifies all the other ants to all bite you at the same time.  So it’s very unpleasant.”

“It makes the land really hard to work.  If you can imagine trying to harvest your taro and other crops while you’re getting stung all the time.  There are people in the Pacific who the choice is to do that and learn to live with it or go and find somewhere else to live.”

“The LFA on the Big Island, are pretty much here to stay.  They’ve spread way too far I think for them to be eradicated.  Many people are beside themselves in trying to manage this.”

Casper Vanderwoude manages the Hawai‘i Ant Lab in Hilo, where little fire ants have been for twenty years.  Bites usually occur when the ants are blown off trees and onto people.

“It can actually be difficult to associate the sting with the ant, because there’s a little bit of delay in the body’s reaction.  Not everybody’s aware they’re being stung by ants, but most people eventually work it out.”

Statewide, Vanderwoude says we’re doing pretty well, actually, keeping the ants in check.  The outbreaks on O‘ahu and Kaua‘i appear to have been stemmed, but there are three active sites on Maui, Waihe‘e, Huelo and Nāhiku.  Vanderwoude is certain there are outbreaks we have not yet detected.

Look closely, this is a piece of coconut frond with Little fire ants on it. The ants are tiny, less thana sixteenth of an inch, and do like to live in trees. People are often affected when they stand under trees or have ants blown onto them from nearby foliage. This is a reference photo from the Hawai'i Ant Lab in Hilo
Credit Hawai'i Ant Lab

“The thing is, with invasive species, it’s such a cross cutting issue.  It affects all parts of society, industries, and development.  It has huge potential as a tool for adaptation to climate change.  I believe it’s one of the best tools in the toolbox.  Basically, the best thing the Pacific can do for climate change, in my opinion, is to make sure their ecosystems are resilient, that they are strong, that they can provide and adapt during these big changes that are happening to us.”

David Moverley says invasive species have got to become everyone’s responsibility, and as a byproduct, this vigilance will bring us closer to knowing what’s supposed to be there.  Check any plants you move.  Wash them before moving them.  If you see anything new or strange, report it to the Department of Agriculture or to quarantine.  Be sure to declare risky items coming into country.

The 2016 World Conservation Congress has issued a multi-step program for increased action against invasive species.  It calls for more resources to develop policies and enforce recommended measures.  It calls for investment, innovation, and partnerships to increase eradications and better understand social and economic impacts.  The new guidelines are called the Honolulu Challenge.  

Find out more about efforts against the little fire ant across Hawai'i at the Hawai'i Ant Lab.