Botta’s Pocket Gopher
Common name: Botta’s Pocket Gopher
Scientific name: Thomomys bottae
Habitat: common in grasslands, open fields, and forest openings
Size: up to 23 cm long excluding tail
Description: Botta’s Pocket Gopher is tan to medium brown and often the color of the local soil. The gopher uses its short, powerful front legs and neck to “swim” through soil and push it away. Its short tail is partly covered in short, coarse fur. It fills its fur-lined cheek pouches with food to carry it into storage chambers in its underground burrow system.
Fun facts: Botta’s Pocket Gophers are very important because they make the soil richer. They push minerals from the deeper parts of their burrows toward the surface. Their burrowing helps make richer soils by mixing air, water, plant parts, animal wastes, micro-organisms and minerals. Richer soil helps the gophers too, because it make plants grow bigger and faster, which makes more food for gophers to eat!
Life cycle: During the year, a female Botta’s Pocket Gopher will have one to three litters (batches of babies). Each litter has about four or five young. Although gophers can breed all year, most young are born during the spring and at the end of summer.
Ecology: Gophers make and live in closed burrow systems, a few inches to ten feet below ground. Their burrows consist of a large den and connecting tunnels. A gopher burrow system can have 15 connected tunnels totaling 200 feet in length! In vernal pool grasslands they stay nearer the surface because the hardpan layer keeps them from digging deeper.
The Botta’s Pocket Gopher is an herbivore. It eats roots, stems and bulbs of plants such as White Hyacinth, Vernal Pool Brodiaea and Field Cluster Lily. The gopher can eat without leaving the safety of its underground burrow. It simply pulls its food into the tunnel through the roof! The Botta’s Pocket Gopher rarely appears above ground during the day. When it does, a Red-tailed Hawk, Great Blue Heron or Great Egret could eat it. It can avoid most of its predators by leaving the burrow only at night. However, Coyotes and the Great Horned Owl are nocturnal (active at night) and welcome a meal of Botta’s Pocket Gopher. Night or day, a California King Snake or Gopher Snake can crawl into a gopher burrow and eat both adults and young.
Conservation: Botta’s Pocket Gopher cannot live where soils have been paved over or are plowed up every year. The quality of its habitat is also decreasing because of Yellow Star-thistle, an invasive plant species from Asia. The Yellow Star-thistle is crowding out the native plant species that the gopher needs for food.
Investigate: Though you are unlikely to see gophers during the day, you will see plenty of signs that they have been there. As you walk across the grassland, soft spots and lumps in the soil tell you that the gophers have been at work.
When they tunnel under vernal pools during the dry season, Botta’s Pocket Gophers make their “gopher mounds” on the bottom of the pools. Visit the pools during the spring bloom and see what species of plants prefer to grow on the gopher mounds. In what ways do you think the gopher mounds and the pool bottom offer different conditions for plants to grow?