2008 Clark’s Nutcracker Use and Monitoring in the Cascade Range

Project: Clark’s nutcracker habitat use and monitoring in the Cascade Range

08 E-8 LorenzNutcrkrAntennaIMG_0998

Attachments:  Okanogan-Wenatchee_Lorenz_2008_ Paper Lorenz_Sullivan

Okanogan-Wenatchee_Lorenz_2008_ Paper Lorenz et al 2011

Agency/Forest or Park/District:  Okanogan-Wenatchee National Forest

Project coordinator:  Teresa Lorenz

Contact:  Teresa Lorenz, 22620 US Hwy 12, Naches, WA 98937, 509-731-5226, lore5748@vandals.uidaho.edu


Carol Aubry, Ph.D., Area Geneticist, USDA Forest Service, Olympic National Forest (principal investigator for Pacific Northwest Albicaulis Project); Martin Raphael, Ph.D., Team Leader, USDA Forest Service, Pacific Northwest Research Station (project advisor and master banding permit holder); Kimberly Sullivan, Ph.D., Associate Professor, Utah State University (academic advisor).

Source of funding

FHP: $9,580

Supplemental funding: $85,905 from Seattle City Light, USDA Forest Service, and Utah State University.

Dates of restoration efforts

2008 through 2010


The objectives of this study were to estimate home range size and examine cache site selection in Clark’s nutcracker.  Additionally, a second objective of this study was to compare the accuracy of four survey techniques for estimating population size in nutcrackers.

Acres/ha treated  N/A


We used radio telemetry to examine space use and estimate home ranges of Clark’s nutcrackers.  We also used telemetry to determine the locations of cache sites, and used standard vegetation surveys to measure features at used and non-use sites.  We estimated home ranges for the summer and autumn periods separately using 95% fixed kernels.

To examine the accuracy of survey techniques for estimating nutcracker population size we conducted point counts, playback point counts, walking transects and Breeding Bird Surveys at three to four sites.  We compared detection rates of nutcrackers between survey methods, and also noted whether surveys succeeded in detecting radio tagged birds that were in proximity to survey points.

Planting? If so, source of seedlings? Resistance?  N/A


Median nutcracker home range size in our study was 413 ha .  We observed that nutcrackers selected for different features when caching at different spatial scales.  At a landscape scale they placed most of their seed caches within summer home ranges, even though this required them to transport caches long distances.  Once within home ranges, they cached seeds either within the forest canopy in high elevation forest types, or in the soil in low elevation forest types.  For caches placed in soil, nutcrackers selected sites with high overstory cover compared to random.

We found that all of the methods used to survey nutcrackers in our study performed poorly for detecting radio tagged birds.  Moreover, detection rates were very low outside of the autumn seed-harvest season, even for untagged birds.  Therefore we suggest that future studies use occupancy modeling to account for poor detectability of nutcrackers, or use other means (e.g. presence of nutcracker-harvested cones) to determine whether nutcrackers are present and harvesting seeds within stands.

Monitoring since completion of the project

            Dates: none

            Plans for future monitoring? none planned

Will outcome meet goals?

Except for some modifications to the larger study design for logistical reason, yes, our study meet with its original objectives.

Future actions/follow up? none planned

Miscellaneous comments

Link to some factsheets that the researchers compiled on the findings of the larger study: http://ecoshare.info/projects/whitebark-pine/