Q. I know a friend with a German cockroach insect infestation and would like to know if releasing a gecko into her house would be a good idea to control insects. She’s tried all the pesticides and bombs, all the sticky traps and sprays, and physical attacks such as stomping and the vacuum cleaner to no avail. She’s losing the roach and insect war, and she needs a safer alternative to an exterminator — like geckos. What kinds do REPTILES readers use?
Andy Patrick
Monticello, Ga.

A. It’s illegal in most states to release non-native animals, so I must first state that I can’t recommend this method despite its widespread popularity. That aside, I can offer some comments from acquaintances who have tried it.

Wall-crawling geckos, such as the popular mixed-species bag of house geckos spreading across many warmer climes, need humidity above what’s inside most U.S. homes. They tend to dehydrate unless a few plants with moist soil or water trays are available to them. A house with lots of insects may sustain them with moisture-filled meals for a while — I don’t want to visit anyone in a house that can do that long term — but the geckos will probably die or find their way outside after a week.

Secondly, house pets such as cats are fatal to geckos. I know of one instance in which the owners released an adult tokay gecko (Gekko gecko) in their home to eat cockroaches. They assumed it would be too big and threatening for their cat to touch — adult tokays average more than a foot in length — but kitty proved more than a match. It snatched the running lizard off a wall before it knew what hit it. A cat that would grab a wild rat in its mouth will have no qualms about catching a mere gecko — even a tokay.