Krista E Dilione
Science and Products
Effects of barred owl (Strix varia) removal on population demography of northern spotted owls (Strix occidentalis caurina) in Washington and Oregon—2019 annual report
Strix occidentalis caurina (northern spotted owl; hereinafter referred to as spotted owl) have rapidly declined throughout the subspecies’ geographic range. Competition with invading Strix varia (barred owl) has been identified as an immediate cause of those declines. A pilot study in California showed that removal of barred owls coupled with...
Wiens, J. David; Dugger, Katie M.; Lesmeister, Damon B.; Dilione, Krista E.; Simon, David C.
Anticoagulant rodenticides in Strix owls indicate widespread exposure in west coast forests
Exposure of nontarget wildlife to anticoagulant rodenticides (AR) is a global conservation concern typically centered around urban or agricultural areas. Recently, however, the illegal use of ARs in remote forests of California, USA, has exposed sensitive predators, including the federally threatened northern spotted owl (Strix occidentalis...
Wiens, David; Dilione, Krista E.; Eagles-Smith, Collin A.; Herring, Garth; Lesmeister, Damon B.; Gabriel, Mourad W.; Wengert, Greta; Simon, David C.
Effects of experimental removal of Barred Owls on population Demography of Northern Spotted Owls in Washington and Oregon—2018 Progress Report
Populations of Northern Spotted Owls (Strix occidentalis caurina; herineafter referred to as Spotted Owl) have declined throughout the subspecies’ geographic range. Evidence indicates that competition with invading Barred Owls (S. varia) has contributed significantly to those declines. A pilot study in California showed that removal of Barred Owls...
Wiens, J. David; Dugger, Katie M.; Lesmeister, Damon B.; Dilione, Krista E.; Simon, David C.
Effects of experimental removal of Barred Owls on population demography of Northern Spotted Owls in Washington and Oregon—2017 progress report
Populations of Northern Spotted Owls (Strix occidentalis caurina; hereinafter referred to as Spotted Owl) are declining throughout this subspecies’ geographic range. Evidence indicates that competition with invading populations of Barred Owls (S. varia) has contributed significantly to those declines. A pilot study in California showed that...
Wiens, J. David; Dugger, Katie M.; Lesmeister, Damon B.; Dilione, Krista E.; Simon, David C.
Effects of experimental removal of barred owls on population demography of northern spotted owls in Washington and Oregon—2016 progress report
Evidence indicates that competition with invasive barred owls (Strix varia) is causing rapid declines in populations of northern spotted owls (S. occidentalis caurina), and that the long-term persistence of spotted owls may be in question without additional management intervention. A pilot study in California showed that removal of barred owls in...
Wiens, J. David; Dugger, Katie M.; Lewicki, Krista E.; Simon, David C.
Effects of experimental removal of barred owls on population demography of northern spotted owls in Washington and Oregon—2015 progress report
Evidence indicates that competition with newly established barred owls (Strix varia) is causing rapid declines in populations of northern spotted owls (Strix occidentalis caurina), and that the longterm persistence of spotted owls may be in question without additional management intervention. A pilot study in California showed that lethal removal...
Wiens, J. David; Dugger, Katie M.; Lewicki, Krista E.; Simon, David C.
Effects of Barred Owl Removal on Population Demography of Northern Spotted Owls in Washington and Oregon, 2015–2018
A new USGS report summarizes research accomplishments and results from the first 3.5 years, 2015-2018, of a study in Oregon and Washington to determine if removing barred owls can improve population trends of Northern spotted owls.