Background
The California Department of Fish and Wildlife (CDFW) started the Spotted Owl Observations Database in 1973. The database tracks both subspecies of Spotted Owl that occur in California.
The
Northern Spotted Owl (Strix occidentalis caurina) occurs in the southern Cascade Range in northern California, across the Klamath Mountains, and down the Coast Range through Marin County. The U.S. Fish and Wildlife Service (the Service) listed the Northern Spotted Owl as a Threatened species under the Endangered Species Act (ESA) in 1990. On August 25, 2016, the Fish and Game Commission (FGC) voted to designate the Northern Spotted Owl as a Threatened species under the California Endangered Species Act (CESA) and adopted the findings on June 21, 2017.
The
California Spotted Owl (Strix occidentalis occidentalis) occurs in the southern Cascade Range in northern California, through the Sierra Nevada, across the Transverse and Peninsular Ranges in southern California, and up the Coast Range through Monterey County. It is a CDFW Species of Special Concern.
The Service, the California Department of Forestry and Fire Protection, and commercial timber interests have used the CDFW Spotted Owl Observations Database to help assess the potential for take of Northern Spotted Owls. The presence of a long-term observation database has allowed land managers, biologists, foresters, and researchers to better evaluate the status and distribution of owl activity centers over time and space.
CNDDB and the Spotted Owl Observations Database
Both subspecies of Spotted Owl occurring in California are tracked by the Department's California Natural Diversity Database (CNDDB) but maintained in the CDFW Spotted Owl Observations Database. The CDFW Spotted Owl Observations Database is packaged with the CNDDB and governed by the CNDDB License Agreement. The Spotted Owl Observations Database has not been integrated directly into the CNDDB because management plans for both Northern and California Spotted Owls specifically address owl activity centers, and because the CNDDB follows a slightly different mapping protocol, the Natural Heritage Methodology of Element Occurrences, it doesn't track activity centers.
The Spotted Owl Observations Database and the CNDDB are accessible together in the CNDDB & Spotted Owl Data Viewer. Additionally, the CDFW Spotted Owl Observations Database is available along with RareFind data updates through the CNDDB monthly updates webpage. For more information on obtaining access to the CNDDB/Spotted Owl Viewer contact our Information Services desk at (916) 324-3812.
Spotted Owl Observations Database Updates
In 2012, the Department's Biogeographic Data Branch (BDB) released an updated spatially-explicit version of the Spotted Owl Observations Database (BIOS layer ds704). In addition to displaying the locations of owl activity centers, the updated Spotted Owl Observations Database now includes the locations of all observations, both positive and negative. Additionally, BDB created the Spotted Owl Observations Spider Diagram layer depicting the relationship between activity center and observations (BIOS layer ds705). In December 2012, BDB revised the format of reports generated from the database, changed the way USFWS Technical Assistance letters were represented in the database, and resumed entering new data. For more information, please refer to our Spotted Owl Database FAQ.
Metadata and explanations of the fields and codes used in the Spotted Owl Database are available with the shapefiles packaged with CNDDB/RareFind or by using the Metadata button in the tool bar of the BIOS Data Viewer.
As of 2014, the database has the ability to store observations that are not associated with an activity center. Previously, any record in the database had to be tied to an activity center. This meant that an observation had to be grouped with an existing activity center or a new activity center had to be created. In some cases, neither option may be appropriate due to the distance from a known activity center or due to a lack of data indicating resident status as described in the 2012 revision of the 
2011 Northern Spotted Owl Survey Protocol (PDF). We are now allowing for stand-alone detections to avoid "invalid" activity centers and long "legs" in the Spotted Owl Observations Spider Diagram layer. These detections are notated by a "POS" or "NEG" value in the MasterOwl field for positive or negative detections, respectively.
In 2014 the Barred Owl Observations Database (ds008 in BIOS) was also reformatted and updated with new data. This database tracks barred owl, Strix hybrid, and unspecified Strix detections. It is updated on a quarterly basis and is available to view in BIOS for CNDDB subscribers or by request. As the barred owl extends further into the range of the Spotted Owl this dataset can help managers assess potential impacts to Spotted Owls in their project areas.
2019 was also an exciting year for the SPOWDB. The symbology (how the data looks on the map) was updated to allow users to see which observations consisted of nests, young, or pairs without needing to open the attribute table. We released the Spotted Owl Observations Management Framework (PDF) which provides a clear description of the processes used to manage the database. Lastly, the QuickView Tool now references the SPOWDB in addition to the CNDDB, providing users with more complete species lists
The Future of the Database
The SPOWDB is a dynamic tool that requires regular maintenance including a consistent input of new data and corrections to old data.
We welcome all historical and new observations – both positive and negative. Negative or “no response” data is extremely helpful in assessing site status such as Abandoned or Invalid. We appreciate the past and current generosity of our contributors in helping us maintain the database and we look forward to continued collaboration in the future.
Please contact our Spotted Owl Database Manager's Spotted Owl account for questions, comments, suggestions, or information about contributing data