If you live in Guanacaste, or just about anywhere else in Costa Rica, you may be familiar with the following situation: You have already turned off the lights in your bedroom and sleep is about to consume you when suddenly you hear TCHAK-TCHAK-TCHAK, or a permutation thereof. That would be an adult male gecko invading your bedroom; a younger female will sound more like chip-chip-chip. What should you do in this case?

There are a handful of gecko species in Costa Rica, and the ones emitting the loud TCHAKs, or the softer chips, are likely to be Hemidactylus frenatus. As previously reported by the Costa Rica Star:

If you see these adorable and loud lizards in your home in Costa Rica, consider yourself lucky. Geckos are not only considered to be harbingers of good fortune in Asian cultures, they also happen to be efficient exterminators. Geckos arrived in Costa Rica from Asian ports where they became stowaways on trading ships. They will enter homes chasing after insects attracted by light bulbs, or they may be seeking warmth. Once inside, they will become active at night and emit up to three different loud clicking calls…

Geckos have two reasons to enter your home. It might be cold outside, which is unlikely if you live in Guanacaste, or your house is full of bugs. Since the latter is far more likely than the former, you should strongly consider allowing the geckos clean up your home with their voracious appetites. For this reason, they are called “limpiacasas” in the southern zone of Costa Rica and Panama. Geckos are also harmless to humans.

If, however, you hear a cacophony of TCHAKs and chips that do not allow you to sleep at night (these are mostly nocturnal creatures), you probably have too many geckos, which is more than likely due to having too many insects in your house. Before you fumigate, consider the following:

• Get a cat. Problem solved.
• Geckos will go where the insects are. Turn on an outside light (or install one) and watch the insects fly and crawl towards the bulb. Geckos will follow.
• Geckos are not happy among mothballs (camphor tablets). Actually, very few leaving creatures are happy around this resin byproduct. Place some mothballs in strategic spots such as corners and on top of cabinets.
• Get used to the geckos and count their calls at night. Nine TCHAKs or chips in succession are considered good luck for your household.

If you insist on fumigating, do it in the daytime and only after you have moved all your furniture and made a lot of noise to alert the geckos. Try to use an insecticide that is labeled as being organic.