Communication with the help of pheromones is equally used by snakes as the vomeronasal system. Typically, snakes use pheromones to communicate about their age, gender, and reproductive condition. Most snake pheromones are lipids that are left directly on the surface, but it has been proven that at least one of the pheromones is airborne and can be perceived from a distance. During wintertime, baby garter snakes use pheromones left by adults to locate them and find communal dens. Communicating with pheromones is especially important during the mating season when the female leaves a trail of pheromones to attract the males. Male snakes often use pheromones to trick their rivals and emit female hormones to deceive their competitors.