Q: What did you say?
A: Hemidactylus frenatus! You know, geckos – those little lizards running around your house, up and down the walls and across the ceilings like they own the place. Hemidactylus frenatus is their scientific name. “Hemidactylus”, the name of the genus, is from ancient Greek, “hemi” meaning “half” and “dactylus” meaning finger, because of the shape of their toes. “Frenatus”, the name of the species, is from a Latin word that means “bridle”, apparently a reference to the coloration of some individuals. The English name that scientists use is “common house gecko”.
Q: Okay, got it! So, how do they do that? Run up and down the walls and stuff?
A: Good question. Scientists have been trying to figure that out for years, and for obvious reasons. Imagine if you could make something in a laboratory that would stick to walls and ceilings only when you wanted it to stick.
Q: So what did those boffins learn?
A: Geckos have millions of tiny hair-like structures on their feet called setae that easily cling to smooth surfaces.
Q: What good are geckos? Are they dangerous? What if one falls on me? Should I try to kill it?
A: Geckos are not dangerous. They are shy, reclusive and nocturnal, so you won’t see them much during the day. Besides, they hang around your ceiling lights at night eating bugs – including mosquitoes – so they are providing you with free insect control. If one falls on you, just brush it off. Keep in mind that it might leave its tail behind: Like some other reptiles, geckos can drop their tails in an emergency.
Q: Drop their tails?
A: Yes, several species of lizards drop their tails as a defense mechanism, a process called autotomy. The detached part usually wriggles for a few seconds to distract the predator, and eventually the lizard grows a new tail, usually shorter and smoother than the original one. Some snakes and salamanders do this, too.
Q: So, they have predators?
A: Yes, chickens love them, and cats like to chase them around the house. Snakes and pigeons also eat them.
Q: Do geckos make a kind of chirping sound? I hear it in the house.
A: Yes. In fact, the Filipino word for gecko, “tuko”, is onomatopoetic, meaning that its name mimics the sound of its chirp. They make that sound when mating or protecting territory.
Q: How do they reproduce?
A: Geckos have two distinct sexes, male and female, and they are oviparous, meaning that they lay eggs. House geckos lay two soft eggs in a dark, protected space, like a crack in a wall, and the eggs harden and hatch in 30 to 60 days. Their lifespan is about five years.
Q: What about their poop? It’s all around my house!
A: Slightly larger than a grain of rice, the droppings are small, cylindrical and dark brown with a white tip, which is uric acid. The droppings show up on walls and surfaces frequented by geckos. Although the droppings themselves are not poisonous, they might contain salmonella. Salmonella causes diarrhea, fever and stomach cramps, which can be harmful to infants and the elderly.
Q: What else do I need to know? Do they bite or carry any diseases, for example?
A: Actually, geckos have tiny teeth and can bite, but they would bite only if threatened. Anyway, they are too small to hurt you. No, aside from the possibility of salmonella in their droppings, they don’t carry any diseases.
Q: Are geckos just found around here, around southern Luzon?
A: Actually, the common house gecko is one of the most widespread lizard species worldwide. Believed to have originated in tropical South Asia, they spread across the Pacific Ocean to many other tropical regions, even Hawaii, where they are considered an invasive species. They also can be found in Mexico, Central America, and northwestern South America. They arrived in Columbia in the mid-1990s and spread to Ecuador in a few years. Nowadays they are found also in the Galapagos Islands and French Polynesia.
Q: Are there other species like the common house gecko?
A: In the genus Hemidactylus, there are about 120 species, but only half a dozen of these are widespread. In the Bicol Region, there are three similar species – the Philippine false gecko, the Bicol hollow-dwelling gecko, and the Bicol false gecko – but they belong in the genus Pseudogekko and are considered to be rare.
Q: How can I get rid of geckos in my house?
A: YouTube has several videos on simple, humane DIY gecko traps. Also, “sticky traps” are available from hardware stores and online retailers like Shopee and Lazada, but they are inhumane. Ideally, the best way to get rid of them is simply to control the number of insects in your house.
Q: Can I eat them?
A: Dumb question. Not sure it deserves an answer. However, since you raised the subject, it should be noted that some cultures in South and Southeast Asia ignorantly eat tokay geckos for their presumed medical benefits. Tokay geckos are larger and more colorful than house geckos, and they are found in Catanduanes Province, but they are protected under the Wildlife Resources Conservation and Protection Act of 2001.
Q: If I can’t get rid of them, what should I do?
A: Why not just live and let gecko!