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Spotted owl in a Douglas-fir
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Northern Spotted Owl
(Revised October 2005)
The northern spotted owl (Strix occidentalis caurina) is found throughout the Pacific Northwest, ranging from southwestern British Columbia to Marin County in California. Following a decline in spotted owl habitat, the United States Fish and Wildlife Service (USFWS) listed the spotted owl as threatened in 1990. Although spotted owls are listed as threatened throughout their range, they seem to thrive in the redwood region of California, specifically on managed timberlands. Current research in northern California suggests that spotted owl densities may be higher on managed timberlands than in quintessential old growth redwood forests. One possible reason for this phenomenon is that in California landscapes where timber harvesting occurs often contain more suitable woodrat habitat, and are therefore more abundant in the primary prey species of spotted owls. However, at present, northern spotted owls are threatened by another owl species, the barred owl (Strix varia), which has made a westward expansion from the east, and is now making its way south along the Pacific Coast. Barred owls are a major cause for concern because they have been displacing spotted owls throughout the Pacific Northwest. Barred owls have been recently detected in several state parks in Mendocino County, but none have been confirmed as of yet on MRC lands.
At present, MRC lands, plus outlying areas up to a quarter-mile from its property line, contain 176 active spotted owl territories, at which 124 have produced young since surveys began. Other activity centers likely have owls but are either too young to reproduce or single males that cannot reproduce.
MRC follows all regulatory guidelines related to spotted owls and works in close consultation with USFWS biologists so that timber operations have a low likelihood of incidental take. Current guidelines require spotted owl surveys in and around any timber harvest plan (THP) and monitoring their activity centers to determine precise daytime roost or nest sites. Collecting this information allows for operational flexibility and ensures that areas ecologically important to spotted owls receive a high level of protection. All THP-related survey and monitoring information is available to the public by contacting the Arcata office of the United States Fish and Wildlife Service.
In 2001, MRC biologists started an effort to survey the entire MRC ownership for spotted owls including all THPs. This effort continued through the 2005 season and will continue into the future so that all of MRC's ownership will have been surveyed for owls. MRC's staff is also monitoring all active spotted owl territories for reproductive success.
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Spotted owl fledgling on a stump.
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This is part of a research effort that will be combined with banding spotted owls to determine the abundance, turnover rates, and productivity levels of spotted owl territories on MRC lands. Combining productivity data with the landscape planning process will enable MRC to examine the potential relationship between habitat distribution and reproductive success for specific pairs of owls, and thus, provide an empirical benchmark for managing owls on MRC's ownership and achieving goals outlined in a future Habitat Conservation Plan (HCP). Overall, MRC's landscape planning process will allow biologists and managers to plan harvest and maintain owl habitat that is distributed equally across the ownership and across time. Monitoring the number of owls on the ownership, their reproductive success and turnover rate will most importantly allow MRC to use adaptive management to change forest practices if owls begin to decline.
The future for growing more spotted owl habitat on MRC land looks bright. Predictions from MRC's landscape planning process shows that owl habitat will continue to increase across the ownership throughout time. However, a current unknown, remains the range expansion of barred owls into MRC timberlands and how this might affect the northern spotted owl.
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