Hog wild: Parks, native plants, animals victims of increasing pig population
Priyanka Sharma-Sindhar Special to the San Jose Mercury News
Dec. 17, 2002
Priyanka Sharma-Sindhar Special to the Mercury News
It's early morning at Skyline Ridge Open Space Preserve, just south of Palo Alto, and park ranger Susannah Anderson-Minshall sets out for a routine inspection in her truck. She soon notices something that makes her slam on the brakes.
A creek that was filled with fresh water until yesterday now looks like a muddy bog. The ground all around is dug up, and ferns and plants lie trampled. She doesn't need to look at the huge, round, footprints in the mud to guess where the blame lies. The culprits are wild pigs, non-native, sharp-tusked, black bristly marauders who have been causing havoc across Northern California's landscape with increasing frequency.
Wild pigs are making life difficult for her, as they are for public parks and private landowners all over California.
There are no precise records to track the population of pigs in the state, but park rangers and county wardens put the figure at somewhere between 700,000 and 800,000 -- and growing.
Earlier this fall, a group of 30 of the tusked boars descended on California Maison, a South San Jose apartment complex, wrecking the landscaping, birthing piglets and charging residents.
Wild pigs also caused thousands of dollars of damage to local golf courses this summer. They have dug up greens, tee boxes and fairways at courses adjacent to Santa Clara County's rural hills. They've hit Summitpointe in Milpitas, Silver Creek Valley in South San Jose, Eagle Ridge in Gilroy and Santa Teresa Golf Course in San Jose. And their activities have continued to harm native animal species -- from damaging habitats such as streams to eating acorns and other common wildlife food.
``I don't know if it makes me mad or saddens me,'' said Anderson-Minshall. ``I'm aware of the beauty that's lost, and aware of the way they come in and change the natural system in a way so that native plants and animals can't survive.''
Parks suffer most
Nowhere has suffered more than Bay Area parks districts.
Henry Coe State Park in Morgan Hill kicked off a $20,000 program this summer to alleviate its pig problem. At 87,000 acres, the oak-studded park is three times the size of San Francisco, and is home for somewhere between three and six pigs per 250 acres.
The pigs breed rapidly, with one pig able to produce as many as 16 piglets a year. Virtually every other Bay Area park district -- from East Bay Regional to Santa Clara County -- shoots and traps wild pigs to limit numbers and reduce the damage they do.
Wild pigs are perceived as a menace because they consistently ruin open spaces, and no one really knows how to stop them. They dig up grasslands and exhume plants, grass, roots and insects; in the process, they choke native species and destroy crops.
They also spoil wetlands by taking their muddy bodies into the water and wallowing around. In addition, they out-compete other species for food. And now, people are speculating that they might have a hand in spreading sudden oak disease. They cause problems in populated areas, say experts.
``Pigs are a mobile population,'' said Anderson-Minshall. ``When it's hot, they move to wet, cooler areas. Those are lawns, gardens and school yards.''
Wild pigs are not native to California. In the 1920s, a big-game hunter brought European wild boars to his estate in Carmel Valley. Some of the animals escaped. They traveled, mated with domestic pigs and spread throughout the state.
Today, their black or russet-colored hairy descendants are found in 56 out of 58 California counties. Weighing up to 400 pounds, with long snouts, coarse, bristly hair and sharp tusks, wild pigs bear little resemblance to small farm pigs.
Despite the lack of extensive research, scientists suspect that pigs cause a host of natural problems. The most obvious is out-competing native species for natural resources. The pig is often referred to by biologists as a perfect acorn-eater.
``Deer, turkey and many other animals need acorns to survive,'' said Terry Palmisano, senior wildlife biologist with the state Department of Fish and Game. Palmisano declined to comment, however, on any direct cause-effect relationships, as there isn't enough research, she said.
But several park officials say that they find a lot less oak-regeneration on their lands, because pigs don't let the acorns grow into trees.
The other concern biologists have is that the pigs can eat large numbers of native species. Being omnivores, they can eat anything that moves, so long as it is small enough for them to kill. The list is long and covers amphibians, reptiles, small mammals -- frogs, lizards, snakes, mice and even small fawns.
Their rooting also causes changes in the habitats of other animals. Anderson-Minshall cites the example of the California red-legged frog.
``It's an endangered species and doesn't have a lot of places to go to,'' she said. ``We're one of the few places, and a non-native species is destroying its habitat here.''
Anderson-Minshall is part of a group at the Midpeninsula Regional Open Space District that has been collecting data on wild pigs since 2000. She doesn't have enough material to be certain, but she suspects pigs have a hand in spreading sudden oak death disease.
``The pathogen that causes sudden oak death spreads though fog, rain, dirt and any organic material that came from the tree such as acorns and leaves,'' she said.
Knowing the pig's fondness for both acorns and dirt, it could pick up the pathogen from one tree and pass it to another while plowing the ground around it, she said.
But according to Henry Coletto, Santa Clara County game warden, the rooting can do some good too.
``The rooting is aerating the soil, and helping it hold more water,'' said Coletto. ``A lot of areas rooted are taken over by forage. A lot of other wildlife -- deer, turkeys, etc. which are native to California -- can feed on the forage.''
Coletto is a minority voice in the Californian pigs question. He puts a different spin on things, questioning the rationale behind pig control.
``That money will not take out more than 15 percent of the pigs in Henry Coe,'' he said. ``And they'll come back. How do you interpret the damage? Eighty to 90 percent of our grasslands are already exotic. So, the question I always ask is -- are they really doing damage?''
Many Bay Area parks and private ranches have hunting programs to try to keep pig numbers down. But even with all the hunting, there's nothing to stop new, nomadic pigs from entering areas that have just been cleared of pigs. State parks ecologist George Gray has come up with a possible solution -- creating spaces where it is illegal to introduce or even harbor pigs.
``If chunks of the state are marked pig-eradication zones, then if landowners or county agricultural commissions regionwide spend that money once'' to kill and fence, ``they'll be done,'' said Gray.
Gray is waiting for the Department of Fish and Game to act on his suggestion, and foresees that a new bill may be required to realize his vision.
Fencing has worked for Pete Opatz, who owns a small vineyard in Mendocino County, and also serves as vice president of vineyard operations for Allied Domecq Wineries. He believes the most feasible long-term solution is to create protective structures that the animals cannot infiltrate.
``But fencing entire tracts of land will not work,'' said Opatz. ``A huge consideration is leaving land for the pigs to traverse. I've elected to fence exclusively the arable, agricultural component of the farm.''
Elliot Katz, president of the animal-activist group In Defense of Animals, based in Mill Valley, believes such measures are worth pursuing. Katz said parks and other agencies resort to hunting simply because it is the easiest solution.
Jeff "Jesse" James - Owner of Jesse's Hunting & Outdoors
You can always tell who's in 2nd place by who's whining and crying the most. - Old hockey coach.
Dum spiramus tuebimur
Advertise on JHO / Fishing Guide/Outfitter reviews / Facebook - JHO / Gear Reviews / Home, Main Page / Hunting Guide/Outfitter Reviews / Links / Photo/Video Gallery / Sponsors / Twitter - Follow JHO / JHO Youtube Channel
"In the beginning of a change, the patriot is a brave and scarce man, hated and scorned. When the cause succeeds, however, the timid join him... for then it costs nothing to be a patriot." -Mark Twain