Measurement data from sample plots characterizing three development stages of a subalpine spruce forest and describing the bird assemblages associated with them
Data on the characteristics of tree stands as well as the birds inhabiting them in the breeding and nonbreeding seasons were collected from a subalpine spruce forest in the Gorce National Park (Western Carpathians, Poland). Stand measurements were conducted on a total of 24 sample plots, with 8 plots established in each of the three studied forest development stages (mature, break-up, and growing-up) selected to represent successive phases of subalpine forest development. The study area designated for each stage was 30 ha. The three study areas exhibited development properties resulting from both biotic and abiotic factors. Tree stands were characterized in terms of the tree layer, saplings, and deadwood. The types of deadwood measured were: standing entire dead trees, snags, stumps, and downed deadwood. In the case of birds, the data included species composition and pair density in the breeding season or individual bird density in the nonbreeding season. Data on bird density are included in the article of the same title in the journal Data in brief in 2020. This article also includes data collection methodology.