http://www.freshplaza.com/article/191019/Roof-rats-are-invading-California-farms
Destroying fruit, nuts and irrigation lines
Roof rats, a common problem for city dwellers, are migrating to California farms and nibbling on everything from avocados to irrigation tubing. According to University of California scientists, last year's wet weather created a perfect environment for the quick-breeding rats to flourish.
Ample rain helped produce an abundance of weeds and weed seeds, a good source of food for rats. It didn't take long for the rats to discover an even bigger bounty in the Valley's orchards and fields.
"Rodents are everywhere and they are opportunists," said Rachel Long, a University of California cooperative extension adviser. "They move in from their surrounding urban habitats to take advantage of any food source they can find. And once that food source disappears they search for food elsewhere."
In Long's 25-year career, she'd never come across roof rats in an orchard until she got a recent call from a grower in the Sacramento Valley who was puzzled by what he thought were squirrels digging holes in his pistachio orchard.
Fresnobee.com reports how Long learned that roof rats adapt depending on their environment. In urban areas, they prefer to live above ground and make their nests in trees and in people's attics. But in rural areas, they burrow underground.
Although it's unknown how much damage the rats have caused this year, UC farm advisers do know that the rats have been found munching on pomegranates, citrus, avocados, pistachios and irrigation tubing.
Publication date: 3/14/2018
