Rooting is the root cause of many problems
At Hollister Hills State Park, off-road motorcyclists have to
compete for the right of way along the dirt trails. Not with each
other
– but with the wild pigs that roam free through the recreational
area.
Rooting is the root cause of many problems
At Hollister Hills State Park, off-road motorcyclists have to compete for the right of way along the dirt trails. Not with each other – but with the wild pigs that roam free through the recreational area.
Wild, or feral, pigs are hardy animals. They are the descendants of domestic swine released by Spanish explorers in 1769 as a source of food and European wild boar released for hunting in 1925. The hybrid animals have spread throughout much of California and their presence is still abundant in San Benito County.
The pigs took over Pinnacles National Monument in the 1960s, destroying natural habitat and since then have tread too much on local golf courses, vineyards and orchards.
Though local golf courses and vineyards haven’t had damage from pigs in the last few months, they know the pigs are bound to be back.
“Certain times of the year, they come and dig up the fairways,” said Scott Fuller, the general manager of the San Juan Oaks Golf Club. “In one night, they can do a lot of damage.”
The rooting behavior of the animals is part of the reason Spaniards released the animals more than a century ago – to help clear away brush and plants.
“Mainly they root in front of the greens or around the greens,” said James Ferland, the clubhouse manager at Bolado Park Golf Club. “In an hour, they can cause $20,000 in damage.”
At Bolado Park, fences have not been a deterrent for the animals.
“They get under fences or around fences,” Ferland said. “There is not really anything we can do, but try to shoo them out.”
DeRose Vineyards has problems with the pigs around harvest time.
“They break the vines and eat the fruit,” said Pat DeRose. “Everyone’s problem is the same. Any crop [the pigs] can get into, they damage.”
DeRose couldn’t say how many tons of fruit the animals have stolen over the years, but he said it is an ongoing problem.
“There is no permanent solution for them,” he said. “They breed and there are more.”
As a non-native species, the pigs have few natural predators. When conditions are good, the animals can breed twice a year. A sow can give birth to as many as 14 piglets in a litter.
San Juan Oaks staff put up a pig fence – a fence that is harder for the animals to root under – more than six years ago. Pig fences are usually made of woven wire mesh and go all the way to the ground where it is anchored to a post so the pigs can’t lift it. But even the fence has not eradicated the problem.
“Sometimes after winter, there might be a washout under the fence,” Fuller said. “If there is a way to get in, they find a way.”
The staff walks the fence and makes repairs when they see breaches in the fence. The fence has lowered the problem, but in 2005 the pigs got in and did a lot of damage during late summer.
“When they do the kind of damage they did in 2005, it has a significant financial impact,” Fuller said. “We have to buy sod and replace damaged turf or we have to scrape everything off, reseed it and grow it back in.”
The pigs invade golf greens and turn over turf in search of grubs.
“They tear it up so bad, you can’t put it back,” Fuller said. “We need to resod, which is expensive or reseed, which is a lot of labor.”
As other property owners in the region have done, San Juan Oaks staff has requested permits from the Department of Fish and Game to hunt or trap the animals.
In addition to the financial impact on commercial endeavors, the wild pigs have a negative impact on native plants, wildlife and soil. Their rooting behavior lifts up soil and causes it to dry out. The plants have a harder time getting water and are often taken over by non-native plant species that thrive with less moisture. Rooting also destroys the habitat of animals that live on or under ground such as amphibians, reptiles, mammals and ground nesting birds. Rooting loosens soil, which is then washed into streams and creeks, leading to poor quality water.
Native animals must compete with the pigs for acorns, insects and fruits – all foods pigs eat.
Pinnacles National Monument is one of the south county locations that has been successful in eradicating wild pigs – though it took the staff nearly a decade and lots of money to do it.
The Monument staff erected a pig fence around the 14,000 acres of parkland. The project started in 1986 and the fence was completed in 2003. Once the fence was completed, the park staff worked with the Institute for Wildlife Studies, a nonprofit organization that works to restore native ecosystems.
“We provided a comprehensive eradication program that included trapping, use of dogs [to search out pigs] and ground hunting,” said Blake McCann, of IWS. “We were able to reduce the pig population greatly and we established a number of monitoring programs.”
In less than three years, the pig population has been eradicated from the park.
“It’s always a sensitive subject when animals are being killed and it’s not something we take lightly,” McCann said. “The real reason we do it is that as an exotic [the pigs] cause so many types of damage to the native ecosystem.”
Melissa Flores can be reached at [email protected].
