Air conditioning units as death traps for introduced Common House Geckos, Hemidactylus frenatus Duméril & Bibron, 1836, on Saipan, Commonwealth of the Northern Mariana Islands, with a discussion of impacts

Several species of house geckos (genera Hemidactylus , Gehyra , Lepidodactylus ) are classic examples of human commensals whose ranges have expanded dramatically through biological invasions, particularly on tropical islands. While these animals are often considered a benign presence and are known for their presence around light sources at night, where they prey on nuisance insects, their attraction to the warmth of electronic components for thermoregulation can lead to significant economic damage. This manuscript details incidents on Saipan, Northern Mariana Islands, where the invasive Common House Gecko ( Hemidactylus frenatus ) caused multiple failures of mini-split air conditioner compressors by short-circuiting internal motherboards. An online review confirms this is likely a broader, underreported issue throughout the range of this species, whose effect on appliances from televisions to switchboards has only been reported from Australia, Cuba, and Taiwan. The synthesis of the new observations with existing literature underscores that the ecological success of these invaders has unexpected consequences relevant to humans as they have extended their impact from ecological to infrastructural domains. We urge greater awareness and proactive mitigation strategies in affected regions worldwide.