Faces of the Restoration: Howard Shellhammer

What first got you interested in the salt marsh harvest mouse?
I was doing my doctoral research at UC Davis in the late 1950s, and my major professor was a shrew guy. That got me into the marshes trapping shrews but soon I became interested in harvest mice. When I came to San Jose State, there wasn't a heck of a lot of information about them. After trapping and studying the mice for five or six years, I petitioned the federal government to declare them endangered. [The government responded, listing the salt marsh harvest mouse as endangered in 1970.]

They are attractive little critters. It became obvious to me that the mouse was essentially a “canary in a coal mine”. If I could do something to protect the mouse, I could do something to protect the marshes, and vice versa.

The salt marsh harvest mouse lives only around the San Francisco Bay and Suisun Bay. Is that because other populations have died out? Are there other estuaries with their own unique marsh mouse populations?
An earlier study looked at genetic evidence, and as far as we can tell, the mouse evolved in the Bay as the marshes were created as sea level rose. Twenty thousand years ago, you could walk to the Farallon Islands and there was no bay. As the bay filled and marshes were created there was isolation of some of the harvest mice.

So no other areas of the world have marsh-specific mouse species?

Not that we know of.

Can you give readers a feeling for the history of public interest in San Francisco Bay marshes?
When Westerners came to the Bay for the first time, the marshes were much more extensive. Everything flat, including much of San Francisco, San Jose and other areas was marsh, marshland edge or upper ecotone. So if you were going to build on flat ground, there was the potential to fill the marshes. There have always been people interested in the marshes, but as time has gone on, more and more people. Certainly there was much more interest starting in the ‘70s. Today, I'm on several groups trying to save some marshes. If global sea level rise is as great as it could possibly be, most of the tidal marshes are endangered.

Since you began studying mouse populations in the 1960s, what has happened to them? Is the picture getting better or worse?
There's no way to assess a Bay-wide population number. When we trap mice, we put out 100 traps 10 meters apart and set them t for four nights. In most areas we get three to four mice; in a great number of marshes we get zero. Sometimes eight to 10.

Most tidal salt marshes are incomplete -- only half there. The upper half of the pickleweed zone is missing, and the upper, or high marsh, zone has vanished. This situation is so common that most people assume what they see are complete and unaltered marshes.

At various places around the Bay, we are turning salt ponds and other areas into salt marsh. There has been a lot of effort. Because of lack of money and other things, we are often left with a steep edge at the back of the marshes, where they meet dikes, cities, garbage dumps and sewage disposal plants. In many cases the marshes abut a dike at a 45° angle. In addition, most marshes are not connected well with one another, so what often looks like one big marshes is biologically a series of much smaller ones.

The mice usually don't have any place they can go when the tides are high. Pickleweed habitat is almost totally inundated every month. And every six months, it really goes underwater. During the very high tides at Solstice, it is chaotic. There are thousands of birds diving into the water, taking out shrews and mice.

There are areas around Coyote Hills, Sears Point and Grizzly Island, where there are hills near the marshes that could provide habitat if they were protected. There are other areas where large marshes can be created, ones that can develop higher areas of escape cover within them. It is a difficult and costly process to create larger marshes, and high marsh escape cover in the marshes that we have. But it has to be done if we are to save not only the mouse but most of the other species as well.

Tell me about your interests outside of biology - I understand you've written poetry and done watercolors and other artwork?
Well, I draw more than I paint. I write some poetry, but I'm not a poet. My wife and I just put a book together for our family called "Songs of Marshes," with pictures and poems – it was very satisfying. I hike and I bike, but that doesn't make me a professional hiker and biker. My wife is a plein air artist by avocation; she does landscape watercolor painting. I tend to do botanicals.

How do you like to enjoy yourself on the Bay?
I belong to a hiking group. We recently went out to Coyote Hills. Most of my time in marshes is purely aesthetic. Life's too short not to appreciate the beauty and color and shade and sunlight and shadow that make the world around us beautiful. The two women in my life helped train my eye to look at the world – often I put my scientific mind to sleep and just enjoy the geese and pelicans. You need to keep both sides of the mind going.

Any thoughts for our readers?
Keep at it. The problems aren't going to get easier. Don't get turned off by the fact that they are getting more complex.