The idea of getting rid of frogs seems to be a controversial subject. Some people claim that frogs are endangered and caution against killing any of them, while others consider them annoying pests that have spiraled out of control in many areas. Overall, frogs are beneficial for the environment because they eat mosquitoes and other undesirable critters. In this way, they can be part of a balanced local ecosystem that enables the possibility of organic farming and gardening. On the other hand, given the right conditions, certain kinds of frogs can multiply to the point that their numbers can create problems for certain types of humans. For example, south Florida seems to be having problems with the Cuban tree frog, which is not native to the area but has managed to migrate there and is now reportedly overwhelming the native frog population, disrupting the local ecosystem, and annoying residents with their noisy mating calls. Meanwhile, Hawaii has been battling a severe infestation of the coqui frog for the past ten years.
Originally from Puerto Rico, this imported species has proliferated so rapidly on the Big Island of Hawaii that they have passed a state law prohibiting people from releasing, transporting, or exporting coqui frogs, which are classified by the state as “injurious wildlife.” After searching through several different Internet sources, I have identified a significant demand for getting rid of frogs arising from frustrated property owners. Many of them are struggling with large numbers of noisy frogs disrupting their normal sleep patterns and even getting into their houses in some cases. Those who keep dogs in their yard also complain because some dogs foolishly attempt to eat the frogs, which often makes them sick because frogs are capable of releasing a poisonous substance called batrachotoxin when threatened. Others seem to like the frogs and don’t want to get rid of them, and animal-loving groups don’t like to use pesticides for this purpose because they claim that these produce a relatively slow and painful death for their beloved frogs.
Personally, I tend to favor organic and environmentally friendly ways of getting rid of things whenever practicable, but also favor lots of free speech and access to information. Therefore, in the classic Karlonian style I have combed through the Internet sources and brought together many different methods for getting rid of frogs that were reported to have some success. The “organic” status of some methods is debatable because although they involve chemicals, they are food-grade substances that do little environmental damage even though they can effectively kill or repel frogs. Here are the methods that I have found so far:Although probably not practical for a large infestation, it is always possible to capture the frogs with a glass or net and simply move them farther away in the hopes that they will take up residence somewhere else. I have had to do this with a few frogs that managed to get into our house after particularly rainy periods. If you have standing water nearby, some people have advised capturing the tadpoles as well if you can find them.
2. Eliminate favorable habitats. Old wood piles, pots, ferns, shrubs, and other relatively dark, damp places can provide convenient places for frogs to hide and breed, so if it is possible to get rid of these without damaging your property, you might want to do so. If you have pets, loose pet food and water dishes can also attract frogs, so these are additional items to consider removing. 3. Turn off outdoor lights. The idea behind this one is that the lights attract bugs, which in turn attract the frogs because frogs like to eat bugs. If you don’t mind keeping the lights off, this can keep the frogs at a safe distance from your house. 4. Kill all of the bugs. By eliminating all of the insects and other critters around your home, you can drive off the frogs by removing their food sources. There are plenty of pesticides available that can kill bugs, and many of them will kill the frogs also because their skin is a permeable membrane that is especially susceptible to chemicals, even ones that are relatively non-toxic to humans.
However, using pesticides will defeat the purpose of organic gardening and may also incur the wrath of environmentalists, pro-animal groups, and whatever gods of nature might exist in your corner of the universe. 5. Bring in natural predators. Interestingly, frogs have a variety of natural enemies that will happily eat them, including snakes, turtles, lizards, crows, owls, hawks, hedgehogs, foxes, raccoons, rats, otters, minks, large fish, and even other frogs. Additionally, many kinds of waterbirds, turtles, snakes, fish, and aquatic insects eat the tadpoles that eventually morph into frogs. Although some people may dislike most of these other animals as much as the frogs, if you’re looking for the “greenest” solution, this is probably it. 6. Use the power of citrus. In the case of Hawaii’s coqui frog problem mentioned above, the Department of Agriculture in that state recently approved the use of citric acid as a method of frog control. Citric acid is found naturally in citrus fruits such as lemons, limes, and oranges, and is also added to many kinds of fruit-flavored drinks to add tartness.
Although generally safe for human consumption, a 16% solution of it (equal to about double the strength of lemon juice) has apparently proved very effective in wiping out large frog populations. Similar solutions may be available at chemical supply or hardware stores. If you could manage to procure some and have a reliable sprayer, this might turn into an interesting experiment. 7. Repel them with moth ball chemicals. Some people have had success with various snake repellents or even repellents that are labeled specifically for frogs. The active ingredients in these products are naphthalene or paradichlorobenzene, the same chemicals used in moth balls. They work by emitting a certain odor that repels the frogs and can be deposited around the perimeter of your yard. However, in sufficient concentration these chemicals can leach into nearby water, killing fish and other types of aquatic life. 8. Bleach them out. Several people have reported that regular strength bleach is very effective at killing frogs if sprayed directly on them.
Note that some people consider this a relatively inhumane method of dispatching them, however, which could incur the wrath of the same groups mentioned in #4 above. 9. Repel them with salt or vinegar solutions. A less drastic version of the bleach treatment is to spray the affected areas with a salt water or vinegar solution. This acts as a repellent by causing a slight burning sensation on the frogs’ feet but will not do any permanent damage or kill the frogs unless you use very high concentrations. 10. Turn up the caffeine. Back in 2001, the U.S. Environmental Protection Agency (EPA) approved the use of concentrated caffeine to control infestations of coqui frogs in Hawaii. This came after a U.S. Department of Agriculture study found that a 2 percent solution of caffeine, which is about 125 times more powerful than what is found in an average cola drink, was 100% effective at killing frogs in laboratory tests. It was also effective in wiping out slugs, snails, lizards, and toads.
Some groups have opposed this experimental use of caffeine for frog control because its effects on other “nontarget” wildlife and the environment in general are not yet known. Below the rather extreme levels used in the USDA experiment, I am not sure exactly what strength of caffeine would be required to make an effective frog blaster; perhaps something just a little stronger than a double espresso or Jolt cola would do the trick. Or we could even try an industrial strength version of Karlonian iced tea, where I have been known to steep the tea bags for an unusually long period of time. As with some of the other methods, it is difficult for me to determine whether they would be considered “organic” or not — caffeine is found in nature after all, but we haven’t really tried to use it as a pesticide either. At any rate, all of these experiments in frog control reinforce what was probably the ultimate takeaway lesson from my years of studying chemistry in college: it’s the dose (as opposed to the notion of a “good” or “bad” drug) that makes the poison!