Zion and Bryce Canyon National Parks are home to all sorts of beautiful wildlife, from the majestic bull elk, bugling in the evening breeze, to the ever social Black-Tailed Prairie Dog burrowing his way across the meadow (and leaving many a hole for a horse to break his leg in).
Among some of the meeker animals here in Utah is the Northern Grasshopper Mouse, about 7 inches long if you include the tail, and dwelling primarily in the prairies and deserts. The Northern Grasshopper Mouse is uniquely proportioned. While most mice have a very long tail, the Northern Grasshopper Mouse’s tail is only about 30% of the total body length. They are grey or even cinnamon in color above, and white beneath, with white covering their feet and the tips of their tail.
When it comes to mice, the Northern Grasshopper is a sure-enough tiger! Unlike the common House Mouse who feeds on household crumbs, the Northern Grasshopper Mouse is 75% carnivorous and preys upon grasshoppers, spiders, crickets, beetles, caterpillars, small mammals such as other mice, and even scorpions! In fact, scorpions make up such a large part of the Northern Grasshopper Mouse’s diet that they are often called the Scorpion Mouse.
The Northern Grasshopper mouse is a burrowing animal, dwelling in burrows they made for themselves as well as left-over burrows from other rodents such as Black-Tailed Prairie Dogs. Because of this, the Northern Grasshopper Mouse is often found making friends with the Black-Tailed Prairie Dog. The Northern Grasshopper Mouse is even known to mimic the Black-Tailed Prairie Dog, standing upright on his hind feet and chirping loudly to claim his territory with his nose pointed up into the air. The Northern Grasshopper Mouse has specific purposes in mind for each of his burrows. The Nest Burrow is used for his primary residence and, since he is a nocturnal animal, he spends most daylight hours inside the Nest Burrow. The Nest Burrow is typically around 10 inches deep and is built at a 45 degree angle. He will usually close up the burrow’s opening each day in order to keep safe and to keep a little moisture inside his burrow in the dry Utah climate. The Cache Burrow is where he stores seeds- even though most of his diet is meat and insects, about 25% of his diet is still seeds and vegetation. There is a possibility that the Northern Grasshopper Mouse even uses some small burrows filled with scent from his own natural oils as Signpost Burrows in order to mark the boundaries of his rather large territory.
The Southern Grasshopper Mouse is generally born between September and February in litters ranging from 2-7. Although they are altricial species, with a gestation period of 32-47 days, and are not able to reproduce until around 3 months, their average lifespan is only about two months.
Nature can be rather cruel, at least in the eyes of us human ones, and it would seem that the primary purpose of the Northern Grasshopper Mouse is a perfect example of such, for that purpose is to carry the plague by means of 57 species of fleas. The plague is transmitted to their friend, the Black-Tailed Prairie Dog, and is a means of keeping the Prairie Dog population in check. Because of their common association with the Plague, or Black Death, it is strongly recommended that you never stick your hand inside any burrows and see to it that your children do not do so either. A bite from either the Northern Grasshopper Mouse or the Black-Tailed Prairie Dog could very easily be fatal or at least send you to the hospital for several months. In fact, due to the Plague, it could very well be argued that rodents such as mice and prairie dogs are the deadliest animals in Zion or Bryce Canyon National Park.