These datasets represent inputs into spatial and temporal models associated with a published study assessing trends and vulnerabilities in the mutalism between whitebark pine (Pinus albicaulis) and Clark’s nutcracker (Nucifraga columbiana, CLNU) in national parks of the North Cascades and Sierra Nevada regions. The study used avian point count data and summary information on whitebark pine abundance and distribution.

This reference provides the two datasets contributed to the temporal modeling analysis within the North Cascades region, specifically Mount Rainier National Park (MORA), as Clark’s nutcracker trends were not discernable at North Cascades National Park (NOCA). For data associated with national parks within the Sierra Nevada region, including Yosemite National Park (YOSE) and Sequoia and Kings Canyon National Parks (SEKI), please refer to: https://irma.nps.gov/DataStore/Reference/Profile/2278594.

1) Whitebark pine data from 29 0.04-hectare circular plots representing eight stands in Mount Rainier National Park, with survey data from 2004, 2007 (9 plots), 2009 and 2015. Basic plot data used to model relationships with Clark’s Nutcracker abundance estimates and trends are summarized by plot and year, including the number of live trees, average live tree diameter, live tree infection rates, and basic site characteristics (elevation, slope and aspect). For modeling and analytical purposes, the data set also includes filled records for plot-year combinations with no survey data, represented in the data as ‘NA’. Data were summarized by plot and year because Clark’s nuctracker density was modeled at the park scale according to park-scale tree metrics, accounting for both plot and stand effects on those tree metrics.

2) Avian survey data represent the count of Clark's nutcracker individuals at observed at point-count monitoring stations, 2005-2016. Avian survey covariates include: ambient noise level, observer, date, hour, presence of forest cover, presence of dense vegetation cover, elevation, aspect, and slope. For modeling and analytical purposes, the data set also includes non-detect records and filled records for transect-year combinations with no survey data, represented in the data as ‘NA’. Data were derived from the highest of three elevation strata, because Clark’s nutcracker were almost never observed in lower strata.