Identification: This compact burrowing rodent is distinguished by blunt head, large upper and lower incisors, fur lined pouches on both sides of mouth, and crescent shaped mounds of soil it digs up. Thirty-three species across the Western Hemisphere, having varied colors and sizes. Major points of difference in genera are the surfaces of their incisors and size of feet and claws.
Physical Attributes: Can fix oxygen found in tunnel environments that offer low concentrations of oxygen and higher carbon dioxide levels through high hemoglobin levels in their blood. Digging and excavation tasks are enabled by superb physical structure of gopher. Powerfully built forequarters, large digging forepaws with large claws, along with aggressive gnawing can be performed with mouth closed because supper and lower incisors are on exterior of mouth cavity.
Activity Periods: Works throughout year, typical workday begins early in the morning to sweep the area for intruders, forage for succulent vegetation, and for tunnel maintenance. Greatest amount of work done is when the soil is most workable, usually after winter soil warms up and soil dries out. Does not go dormant. Will take prolonged rest periods and when temperatures or humidity reach extremes, the gopher will go to deep nesting runway systems and live off of stored food caches. (See diagram of system).
Social Structure: Male systems don’t overlap. Males overlap female systems. Female systems don’t overlap. Home range sizes are dependent upon carrying capacity of local food supply. Typically territorial or solitary. Avoid each other unless during highly charged breeding cycle and weaning process. Female will drive out juveniles to new habitats after weaning. A lesson lost on the contemporary American Family.
Habitat: Live in seclusion in underground tunnel systems,which are rigorously defended. Prefer friable soil that has better than average gas exchange. Systems are typically made up of shallow feeding tunnels that run downward into deep nesting tunnel systems that can be several feet underneath the shallow systems. Average shallow tunnel depth is between 6-12″. Gophers can heave up large amounts of soil in random mounding patterns, each forming a crescent shaped mound. Mole mounds are conical in shape and form almost linear directions in their digging patterns. Gophers will forage above ground very near the tunnel opening for food and nesting material. ( See tunnel cross section diagrams). They can create up to 70 mounds a month. Will back fill old systems with new soil diggings, same for moles.
Food: Gophers seek food several ways; feeding above grounds, feeding on vegetation dragged into tunnel system, and direct consumption of roots, all mainly located by odor. Generally thought of as a strict herbivore that eats grasses, shrubs, forbs, and trees but research has revealed that insects make up a small but definite portion of their diet. They prefer perennial forbs that are succulent source of nourishment. Annual plants that provide fleshy underground nutrition and moisture are also highly sought after. Will dig into snow layer to find winter food supply, leaving earthen tubes above ground after snowmelts
Abundance: Typically can find 6-20 per acre in a favorable digging and feeding environment. Higher levels are often found in alfalfa, were populations can reach into the hundreds per acre.
Breeding Season: March through April. Breeding follows improved food and temperature conditions. Male gophers will construct and maintain linear systems that seek to overlap adjoining female tunnel systems during this cycle. Will breed after reaching sexual maturity the following spring. Litters average 4-6 but litter sizes vary with species. Gestation period 18-19 days. Multiple litters in lower elevations and milder climates with good to overabundant food sources. Breeding can occur throughout the year such as in alfalfa fields located in warmer growing location, like Arizona and California.
Predation: Badgers, spotted skunks, and some snakes can get some gophers in tunnels. Hawks, owls, coyotes, bobcats, raptors make up biggest threat as gophers feed or are dispersing above ground.