Logging of the largest trees in the Sierra Nevada’s national forests ended in the early 1990s after agreements were struck to protect species’ habitat.
Logging of the largest trees in the Sierra Nevada’s national forests ended in the early 1990s after agreements were struck to protect species’ habitat.
But new research reported Dec. 6 in the journal Diversity and Distributions by University of Wisconsin–Madison ecologists shows that spotted owls, one of the iconic species logging restrictions were meant to protect, have continued to experience population declines in the forests.
Department of Forest and Wildlife Ecology graduate student Gavin Jones, Professor Zach Peery, senior scientist R. J. Gutiérrez, and their colleagues say the owls in the area may still be paying an “extinction debt” that was created by historical logging of large trees. These large, old trees the owls rely on are slow to grow back, meaning the owl population could still be showing the effects of logging that ended decades ago.
Compared to nearby national parks, which were never extensively harvested, national forests in the area were more extensively logged until the 1992 restrictions on harvesting large trees and logging near owl habitat took effect. The new study shows that spotted owl populations are stable in national parks. But in the more recently logged national forests, the researchers suggest historical logging of the largest trees may be contributing to the continued declines in owl populations they observed.
Read more at University of Wisconsin-Madison
Image: While California spotted owls (left, adult; right, juvenile) typically perch and roost in smaller trees like this incense cedar, their nest trees are often several feet in diameter. (Credit: Danny Hofstadter)
