In a study published in BMC Public Health, an open access journal, tilapia was introduced into abandoned fish ponds at an altitude of 1,880m and the effect measured over six months on the numbers of mosquito immatures.

For centuries, the Zoque people of southern Mexico would venture each year during the Easter season deep into the sulfuric cave Cueva del Azufre to implore their deities for a bountiful rain season.

As part of the annual ritual, they release into the cave's waters a distinctive, leaf-bound paste made of lime and the ground-up root of the barbasco plant, a natural fish toxin. Believing the cave's fish to be gifts from their gods, they scoop up their poisoned prey to feed upon until their crops are ready to harvest.