The Luck of the Bay Saver! Save The Bay Educator and Girl Scouts See Rare, Endangered Mouse

by Jill Jacobson

What does a Bay Area resident have to do to find the luck-bringing creature, the Salt Marsh Harvest Mouse? For years, I have read the tales of ecologists spotting these tiny creatures in the wee hours of the night and imagined it happening to me. Up until this past Saturday, the only mouse I had ever spotted was the one stuffed in an exhibit at the Palo Alto Baylands Nature Preserve. As one must conclude, I was skeptical and wary of the possibility that I may one day be lucky enough to see one of these elusive creatures.



My luck has changed! Finally after five years leading over 450 educational programs in the San Francisco tidal marshes for Save The Bay, I have successfully spotted a Salt Marsh Harvest Mouse! I am honored to be one of the first with Save The Bay to see this rare and tiny creature that is endemic to the San Francisco Bay.

The mouse was first spotted by a few Girl Scouts this past Saturday at 11:42 a.m. during a Save the Bay Girl Scouts volunteer planting day at the Palo Alto Baylands. One of the girls tugged on my sleeve and said "Jill, there is a mouse in the water, over here! Look!" The other girls were exclaiming all at once "How cuuuuttttee!" Sure enough, there was the Salt Marsh Harvest Mouse swimming at the water's edge. Cautiously, I signaled to the girls to step back to observe the mouse silently from a distance so as not to scare it away.

What makes spotting the Salt Marsh Harvest Mouse so lucky?
To start with, this creature is incredibly tiny, said to fit on the tip of your thumb and weigh about as much as a nickel or quarter. In addition to being small in size, this creature is endemic to the San Francisco Bay wetlands. With only 10 percent of the Bay wetlands remaining, the population of the Salt Marsh Harvest Mouse has declined over the past century, putting it on the endangered species list with a population under 2000. Finally, this mouse is nocturnal, making it nearly impossible to see the mouse under the sunlight.

So, why did we spot this mouse?
This mouse lives primarily in the pickleweed, a low zone tidal marsh plant that is often submerged under the brackish water during high tide. During the high tide, the mouse usually finds shelter in the mid zone plant species, like alkali heath or gumplant. During extreme high tide events, like this past Saturday, this mouse must find shelter in the higher zone plant species which sometimes do not exist, due to the development of roads, trails and parking lots. Over the past few years, Save The Bay has been working in partnership with the Palo Alto Baylands to restore these high or “transition” zone plant species to provide shelter and habitat for species like the Salt Marsh Harvest Mouse.

What does a Bay Area resident have to do to see a Salt Marsh Harvest Mouse?
Become a Bay Saver and join Save The Bay as a volunteer to protect and restore the habitat for the Salt Marsh Harvest and the hundreds of other animals that call our wetlands home! We cannot guarantee you will be lucky enough to spot this creature, but we can guarantee you will see wildlife and have a great day out on the beautiful San Francisco Bay!

A Mouse in the House

by Darcie Collins, Ph.D., Habitat Restoration Director

$30 million in the stimulus package for a mouse? That was the claim in last Thursday’s Washington Times. GOP officials, arguing the new stimulus package is stuffed with Democratic pork, charged Nancy Pelosi with earmarking $30 million of the $780 billion package to protect the salt marsh harvest mouse, an endangered animal endemic to the marshes of the San Francisco Bay.

The story evolved like this: last week, a House Republican staffer circulated an email claiming an unnamed Federal Agency would spend “thirty million dollars (of stimulus money) for wetland restoration in the San Francisco Bay Area—including work to protect the salt marsh harvest mouse.” Although there is no specific language in the bill indicating the money would go explicitly to protecting the endangered animal, the staffer held to this claim: “The bottom line is, if this bill becomes law, taxpayers will spend $30 million on a mouse.”

Pelosi’s staff disagreed. “There are no federal wetland restoration projects in line to get funded in San Francisco,” Pelosi spokesperson Drew Hammill said. “Neither the Speaker nor her staff have had any involvement in this initiative. The idea that $30 million will be spent to save mice is a total fabrication.”

In truth, it's not a total fabrication. But many San Francisco Bay wetland restoration projects—earth-moving, planting, fence and road building, and creating wildlife viewing areas and parking lots—are currently at a stand-still due to inadequate funding. These “ready-to-go” projects are prime for the stimulus package. And they would help protect the salt marsh harvest mouse.

So what is wrong with a project that benefits an endangered species and creates job opportunities? Unfortunately the little mouse has been getting a bit of a bad rap.

In wetland restoration, the salt marsh harvest mouse operates as an “indicator species." Indicator species are very sensitive organisms that respond to extremely small changes in the environment and are often used to indicate pollution and other impacts in ecosystems. In the case of the salt marsh harvest mouse, the loss of San Francisco Bay tidal wetlands and salt marshes has caused a dramatic decrease in the harvest mouse population, resulting in its addition to the Endangered Species List in 1970.

But just as sensitive species can be indicators of disturbance, they are also indicators of healthy systems, and restoration biologists often use these species as evidence of the successes of restoration work.

So what does the mouse-bashing mean for SF Bay restoration ?

Healthy salt marshes are vital for a sustainable Bay ecosystem, which helps combat the effects of global warming and leads to a sustainable fishing industry, improved water quality, and increased tourism and recreation. GOP officials may bash the little mouse, but a thriving salt marsh harvest mouse population indicates a healthy wetland ecosystem. And since salt marshes are the lungs of the Bay—providing habitat to hundreds of fish and wildlife species, trapping pollutants from urban areas before they reach the Bay, capturing carbon from greenhouse gases and providing flood and erosion control—this is a good thing.

The proposed stimulus package includes $30 million to restore San Francisco Bay wetlands, which ultimately protects the salt marsh harvest mouse. Some call it pork; others call it cheese. I call it a good investment for our Bay.

Learn more about Save The Bay's wetland restoration program.