Watching Out for All the Animals
by Susan Kelly
Look at San Francisco Bay from one of the surrounding hills and you'll see a beautiful sight. But if you look closer at the edges of the bay you will notice that development has encroached along much of its shoreline. There are remaining pockets here and there where the marshes have been deliberately saved or perhaps just not built on yet. These pockets are critical habitat to the wildlife populations who live there.
Although the marsh supports many species, three animals receive the most attention when you talk about wildlife in the marsh. They are the endangered California clapper rail and salt marsh harvest mouse -- and the red fox who preys on them. The rail, a medium-sized marsh bird, lives only on the San Francisco Bay. They hide and nest in those remaining areas that have sufficient amounts of pickleweed and cordgrass. The mouse is a very specialized mammal in that he can tolerate high levels of salinity. Although he likes fresh water, he can drink salt water and eats the very salty pickleweed in which he makes his home. When high tide comes, both the mouse and the rail use the cordgrass to hide from predators.
The red fox gets attention because he is deemed a non-native species (introduced in the 1800s) and he preys on the rail and mouse. Over the years local and state agencies have permitted several predator control programs to trap and kill red fox living in the bay marshes, in an effort to increase the numbers of the endangered animals. Clapper rail numbers have risen and the salt marsh harvest mouse is doing all right, however it is far from certain that predator management programs are responsible for this increase. What is clear is that the red fox and other predators are not the number one reason for these animals are now endangered. That distinction falls to the loss of habitat.
Start a conversation about saving endangered species and all kinds of uncommon subjects come up: habitat loss, habitat fragmentation, carrying capacity, non-native species and predator control. Habitat loss is just what it says: the living space for an animal is lost to development or some other type of destruction or encroachment. Habitat fragmentation occurs when habitats that once were connected are now separated by housing, logging or another barrier. Carrying capacity refers to the number of animals that a given area can support with adequate food, water and shelter. Non-native species are animals who were introduced to the area, and predator control is the removing of animals who may prey on the endangered animals you want to save.
Last fall the Peninsula Humane Society, along with the Homeless Cat Network, In Defense of Animals, the Animal Protection Institute and several other animal welfare groups, became involved with a predator control program in Redwood Shores. The program, which was originally scheduled to go into effect in October 1998, was required by the United States Fish and Wildlife Service (USFWS) because Redwood City needed to raise the levee along Redwood Shores Peninsula to protect the housing and business developments located there. To mitigate any damage done to the habitat, or to the California clapper rail and the salt marsh harvest mouse, the USFWS required Redwood City to pay for a trapping program that would reduce predators. Their assumption is that with no predators, the endangered animals would have a chance to recover their numbers if they were, in fact, effected by the levee work.
Close to home
The species that are being targeted for elimination are the red fox, raccoon, skunk and feral cats. After being caught in a trap, the animals would be euthanized. The method of trapping will be humane box traps and possibly padded leghold traps. (The recent passing of Proposition 4 may mean that the padded leghold trap will not be used, although state and federal laws superseding Prop. 4 do allow for their use in the protection of endangered species. In general, however, federal agencies follow local policy, in this case Prop. 4.) The animals mentioned above are not the only predators who take the endangered animals. There are a few species of birds of prey that take other birds; rats would take the eggs and young, as would herons and gulls.
Historically, trapping has been the way to solve wildlife problems when it comes to predators. It is a cheap and efficient way of eliminating animals. The United States Department of Agriculture(USDA) estimates that it will cost $300,000 over five years (spending 20 hours a week) to trap out Redwood Shores' offensive animals and save the rail and mouse. After five years the program will be re-evaluated and continued or ended.
How can one justify killing one set of animals to save another when the reason they are endangered in the first place is loss of habitat? Is there an alternative? We at PHS think so, as do several other animals protection groups and many citizens of Redwood Shores.
First, we must take a good look at the Bay Area's relentless development. If these animals are, in fact, important to us, their habitat must be saved. And this doesnít mean curtailing development only around the marshes. All the water that flows from our homes goes to a treatment plant and ends up in the bay. All this fresh water is changing the salinity of the marsh, impacting the salt marsh harvest mouse. There is no point killing off predators if the habitat cannot support the endangered animals. Sometimes just the fact that human activity takes place so close to a sensitive area may render it unsuitable.
Second, we must establish through recent studies that predators really are a threat to endangered animals. Agencies often put programs in place because it is standard operating procedure, not because it is the most effective solution.
Third, nonlethal methods for removing animals, such as box trapping, should be explored. Predator control projects rely on leg-hold traps because they work fast, but these traps are also very cruel. We believe that patience and humane box traps should be tried first. Further, we need to explore the feasibility of relocating the predators in the immediate area once removed from the sensitive zone. Water barriers and fences would humanely and effectively keep them out of the sensitive area.
Fourth, all domestic animals trapped should go to an animal control facility to be properly evaluated, and all injured target and nontarget animals should be brought to a wildlife rehabilitation facility for treatment and disposition.
Finally, depending on the area, exclusion of people recreating in the area during sensitive times of the year, such as breeding and raising of the young season, should be an option. This could be done with fencing and educational signs so people understand how they are helping support endangered species.
It is time for the USFWS and the USDA to take a look at how they conduct business in regard to their predator management program. What may be a viable solution in a rural area of California may not be acceptable in a suburban area like Redwood Shores. Groups that are usually at opposite ends of the spectrum on animal issues need to sit down and work out solutions that accomplish a common goal -- in this case, the saving of not only endangered species but of all the wildlife involved. We hope to accomplish this very thing by working with the USFWS, USDA the City of Redwood City and other animal protection groups.
(Susan Kelly is manager of the Wildlife Care Center at PHS.)