Pocket gophers are an important and very common mammal in many habitats in our area, so it seems appropriate to learn a little more about them. Most people know them as pests of ornamental plants or crops, but they play important roles far beyond that pestiferousness. And, just look at how cute they can be- photo by Flickr user Chuck Abbe:
What is a Pocket Gopher?
Why is this critter called a pocket gopher? No, it’s not because of some 1970’s fad of domesticating gophers and putting them inside pocket protector-lined pockets. BTW, this fad fantasy must include pocket protectors because gophers have sharp teeth that they habitually gnaw with to wear them down…without such nervous-seeming gnawing, their teeth would be 11” long by the end of the year. This fad could really take off one day because pocket gophers are not legally protected by the State!
Back to the subject at hand…the ‘pocket gopher’ name comes from odd pockets that these critters use as their cargo containers, hauling soil or food. Those pockets extent from the cheeks back to their shoulders. Inside those furry pouches, they haul food into their burrow, creating food storage piles in a deep portion of their burrow system. This food pantry also serves as their sleeping, baby raisin area, so food’s close at hand. That makes me think that maybe there’s a niche for food-storing bedroom furniture for humans!
Our local species of pocket gopher is the most widespread in California, and so there’s lots of information around about its natural history. Our species, Botta Pocket Gopher, is almost everywhere in the state except the high Sierra Nevada. Like most pocket gophers, the males of this species are larger than the females. So, its likely that the Jury Room sign that was posted for years ‘Home of the Giant Gopher’ referenced a male. Not that you’d try, but you tell pocket gopher species apart from where they live and then the size of their rear feet, the shape of their ears and the relative size of the dark area around their ear.
Pocket gophers are very territorial, protecting their extensive burrow system which represents the extent of their feeding ground. The size of their territory depends on how much food there is, but they range from the size of a tennis court or, sometimes, you can fit 10 gopher territories in the space of a tennis court. If you kill a gopher, its burrow system won’t be vacant for long…
Waves of Dispersing Gopher Young
During breeding season, gophers become less territorial, allowing visitors into their burrows, which seems sensible for reproduction. Where people aren’t watering plants, and the summers are so very dry, pocket gophers have a single breeding season in late winter. They bear 2-5 blind babies (aka ‘pinkies’). Gophers kick these offspring out of their burrows as soon as they are weaned (40 days after birth), and those young have to find a place to live. Those dispersing gopher children are why folks suggest leaving root protection cages out of the ground 6 inches. That wave of dispersing gophers will try to occupy whatever burrows they find…including the burrow complexes that have been abandoned by other gophers due to trapping or old age. People think that our gophers only live 3 years.
Gophers Drought Solutions
Gophers are soil engineers and are so good at their work that they are known to be an important solution to California’s water crisis.
Some have suggested that restoring mountain meadows in the Sierra Nevada could store as much water as two new giant reservoirs. Part of this would be done with reintroduction of a different rodent, the beaver, but another part is already under way by the pocket gopher. Pocket gophers are excellent hydrological engineers, assuring infiltration of snow melt and rain through the soil through their burrows, which include specific drainage architecture. Gophers can drown and need to breathe air, so their burrow systems must accommodate drainage for the rainy season.
Native Meadow Gardener Gopher
The better local natural historians around us will already know about the super-diverse and super-interesting mima mound meadows around Santa Cruz. These are caused by eons of soil movement by gophers, which means that they are literally “ecosystem architects.” Atop the mima mounds, there are poppies, lupines, purple needlegrass and other ‘dry’ loving species; between the mounds there are buttercups and rushes as well as streams and pools of water weeping from ancient gopher mounds during the winter. Dry and wet gopher-created ecosystems in close proximity makes for extraordinary species diversity.
Gopher Burrows: Habitat for Other Creatures
All of those gopher burrows are quite inviting to other creatures. In other places, scientists have described insect species that only live in gopher burrows. I see a species of brown fly come out of gopher burrows around here- there’s probably much more to be discovered. Pocket gophers don’t much like to invite things to enter their homes, so they plug their holes with a distinctive soil plug. However, I’ve seen newts poised for nocturnal forays at the mouths of gopher burrows. Others have seen rare California tiger salamanders using gopher runs. Those tunnels would of course be cooler and moister than the surrounding habitats in the summer. I commonly see the aptly named gopher snake winding its way from one gopher hole to the next, only the middle of its body visible. If gophers plug their holes, how do the snakes find their way in? Somehow they know…I saw a gopher snake recently quickly and energetically ‘dive’ into a gopher-strewn dirt pile and disappear quickly. Many are thankful for gopher predators because of the damage gophers can do to human-plants. Gopher snakes and alligator lizards are the most effective gopher control, because they can get down in the gopher burrows and eat the pinkies, controlling many gophers at one sitting.
What to do About Gophers
There are plenty of websites with information about how to, and many tools to, kill gophers, but is there another way to coexist with these creatures? I have spent a fair amount of money and time killing gophers or protecting plants from gophers using buried metal caging, and I have a few suggestions for gopher coexistence.
Lawns are pretty much passe at this point in California, so how about letting gophers make their homes in what would have been a lawn? The only drawback I’ve experienced is the mounds of dusty soil that they pile up, making a mess of what I want to be level ground without trip hazards. Use a gravel rake and smooth those mounds out and you’ve got a great seedbed for wildflowers to sprout from next spring. Yes, with all of that soil disturbance, gophers are doing a great job of preparing wildflower beds- poppies, lupines and other wild pea relatives, new yarrow seedlings, redmaids, owls’ clover, and lots more appreciates that fresh ground.
Another thing to do is choose plants that gophers don’t bother. Colt rootstock for cherry trees is highly resistant to gophers. Wild rushes (especially Juncus patens) stay green through the summer and are so tough that gophers can’t destroy them.
A final solution is to cultivate meadow voles, which are superior at running gophers out of their tunnels. Voles like lots of mulch- put mulch around and voles proliferate…and the gophers run away (or die at the homicidal teeth of the vole militia).
I’d like to see more discussion about human-gopher coexistence, so these important creatures can continue to do so much good across our region.
-This post originally presented as part of Bruce Bratton’s BrattonOnline.com weekly blog…check it out!