Data from: Declines in pinyon pine cone production associated with regional warming

Global climate change is expected to produce large shifts in vegetation
distribution and has already increased tree mortality, altering forest
structure. However, long-term shifts will be partly dependent on the
ability of species to reproduce under a novel climate. Few studies have
examined the impact of climate change on the reproductive output of
long-lived ‘masting' species, or species characterized by episodic
reproductive events. Here, we show that seed cone production among pinyon
pine (Pinus edulis), a masting species, declined by 40% from the 1974
decade (1969–1978) to the 2008 decade (2003–2012) in revisited stands
throughout New Mexico and northwestern Oklahoma. Seed cone production was
highly correlated with late summer temperatures at the time of cone
initiation. Further, declines in seed cone production were greatest among
populations that experienced the greatest increases in growing season
temperatures, which were the populations located at the cooler, upper
elevations. As growing season temperatures are predicted to increase
across this region over the next century, these findings suggest seed cone
production may be an increasingly important bottleneck for future pinyon
pine regeneration, especially in areas with greater increases in
temperature. Declines in seed cone production may not only affect pinyon
pine population dynamics but also the various wildlife species that rely
on pinyon pine seeds. Because pinyon pine has similar reproductive
strategies as other semi-arid pine species, increasing temperature may
negatively influence reproductive output of other conifers. Further
investigation into the full geographic and taxonomic extent of these seed
declines is warranted.