Hi'iaka's Healing Herb Garden

Croakin’ Coquis: The Unapproved Control

Imagine, if you will, our beautiful Big Island before the arrival of Captain Cook. It truly must have been a paradise! Just think, no mosquitoes, no fruit flies, no mongoose, no coqui frogs. Things have changed a lot since that fateful day in 1778, and we must now cope with all of the unpleasant things, like mosquitoes, that can sometimes ruin a beautiful day outdoors. We’ll never get rid of all the invasive species, but I believe we should be doing our part, on our own properties, to control as many unwanted plants and animals as we can—for the benefit of the ‘aina and our own lifestyles.

What if there were a common, relatively inexpensive, natural product that could easily be applied to eradicate some members of a most unwanted species, the coqui frog? But what if this remedy were illegal because a governmental agency must first approve it before we can legally use it? And what if that agency is known to often take years to pass the simplest measures?

The currently-approved chemicals for coqui eradication are hydrated lime and citric acid. However, Mark Munekata says they don’t work. “Lime doesn’t kill the ‘pregnant’ females,” he told me, “even if they are placed in a 6 percent solution of lime overnight. They go into a ‘torpor,’ which is what they do during droughts. Then they are fine.” Lime is also toxic to human’s eyes and respiratory systems if contact occurs. Munekata also says, “Lime doesn’t stay active for more than a day, even with no rain. Baking soda stays active until it rains. Lime is ‘Russian roulette’—it can really hurt you. Soda is safer.”

According to the University of Hawai‘i College of Tropical Agriculture’s Web site, “citric acid anhydrous is a highly irritating and corrosive chemical… avoid eye, skin and respiratory irritation. It can be toxic to sensitive plants, plants that are stressed, or young, growing plant parts, causing leaf spotting or yellowing.”

Munekata is conducting experiments on private land with common baking soda (sodium bicarbonate), and has also conducted an independent study that showed this substance is effective on all stages of frogs—males, females, juveniles and females carrying eggs—within 10 minutes of application. It is known to be quite safe for use around humans (see “Cautions”), animals, plants, households, vehicles, but is DEADLY on the frogs. The Environmental Protection Agency classifies baking soda a “minimum risk pesticide” and “only needs the State of Hawai‘i to apply for a ‘Special Local Need’ (SLN) for emergency use to enable us all to use it and purchase it with community grant monies,” according to Munekata’s literature. But, he claims, the Mayor's office and the Department of Agriculture, who could move this through the EPA in Washington in 30 days, are not making it happen. Munekata is circulating a petition, which, with enough signatures, will enable the EPA to approve baking soda.

Because baking soda has not yet been approved by the State to treat frogs, we should not use it, but the word has gotten around, due in part to a KGMB-TV piece on March 2, 2007. Jim Mendoza logged this story on their Web site:

“They are tiny but their annoying sound is extremely large. The call of the coqui frog, especially a coqui choir, can drive you crazy. Mark Munekata tried lots of things to rid his Hilo property of coqui. He said the magic potion was in his refrigerator. He puts baking soda in his homemade traps.... He puts in a male coqui to call female frogs. When they hop in, the baking soda coats their bodies. The results are always the same—the coqui croak. ‘If it's a hot day and the frog contacts it, he can die within a minute,’ Munekata said.”

A homeowner in the Pepe‘ekeo area told me, “I have personally used this on three sites that I could not get under control with lime, citrus, or handcatching, and I am now at either 100 percent kill or 97 percent kill in all three sites with one application. I cannot say how wonderful it is to be using a product that I believe is not harmful to my health.”

However, there are potential disadvantages to baking soda. Another person in Pepe‘ekeo says the cost can be prohibitive—especially for large properties. “Soda isn't a perfect solution, yet, for large properties with large infestations. The cost is NOT cheap: $32 per 50 pound bag, versus hydrated lime at $11 for 50 pounds, and the lime goes much farther. We sprayed a small area of our place with soda and used half a bag, whereas a bag of lime will last a far longer time. In a place like ours, surrounded on four sides by wild, untended property, we need to spray the perimeters every four weeks to keep the noise level tolerable and the critters from getting into the orchard and under our bedroom windows. So, we are covering the perimeter of a five acre area, and at the cost of soda, we could easily spend $500 a month on the stuff. That is not possible.”

Munekata’s bottom-line opinion about the use of lime and citric acid is this: “Doing the same thing over and over again and expecting a different result is the definition of insanity.”

Cautions

As with any substance, there are risks with baking soda. Safety gear, including goggles, gloves and a long sleeved cotton shirt and long pants should be worn to lessen the continued exposure to sodium over time, especially for individuals with high blood pressure. Succulent or tender plants like Impatiens or ferns may show marginal salt damage to their leaves: It’s good to rinse them off after application.

On the Web:
ctahr.hawaii.edu/coqui/spray.asp
kgmb9.com/kgmb/display.cfm?storyID=10681
coquifrognews.blogspot.com