As with all predators, southern grasshopper mice require large territories and guard them fiercely against all intruders.
As with all predators, southern grasshopper mice require a large territory of two to three hectares in order to find the amount of food they require to survive. The territory size may equal the home range and may occur in male-female pairs.
A male and female along with their offspring occupy a larger home range for burrowing compared to males and females alone. On average, males have a home range of 7.8 acres, while females occupy an area of 5.9 acres.
The home range of southern grasshopper mice males in the Chihuahuan Desert during the non-breeding season was observed to be smaller compared to the home range of males during the breeding season. In contrast, there was not a significant difference between the home ranges of females during the breeding and non-breeding seasons. The average home range of adult males was slightly greater, about two to three times bigger, compared to adult females during the reproductive season. Although this is a big difference, these results were also not very significant. The larger home range of males during the reproductive season might be a strategy they use to maximize the number of encounters they could have with potential female mates when trying to reproduce.
The home ranges between southern grasshopper mice are not too far from each other, with an average maximum distance of 118.4± 8.0 meters, but are widely separated from neighbors.
Adult males tend to be highly territorial and guard their large territories fiercely against all intruders. Their efficient spacing is facilitated by high-pitched calls and vocalizations made at night to serve as territorial advertisement.
Southern grasshopper mice tend to maintain a specific place of residency for a longer period of time compared to other mammals.