Alpine vegetation trends in Glacier National Park, Montana 2003-2018

This dataset is focused on alpine plant species presence/absence, species turnover, and trends in species abundance on four mountain summits in Glacier National Park, Montana, USA from 2003 through 2014. Two summit sites were established in 2003 on Dancing Lady and Bison Mountain, east of the continental divide. Two additional summit sites were established in 2004 on Pitamakin and Mt. Seward, also east of the continental divide. This multi-summit approach to monitoring alpine plant species follows the protocols of the Global Observation Research Initiative in Alpine Environments (GLORIA) that were initiated by the University of Vienna in 2000 and which have been refined and revised since then. GLORIA summit sites now exist throughout the world. Current protocols are available at: https://gloria.ac.at/downloads/manual. Plant surveys took place every five years during peak alpine plant growing season in late July and August on all aspects of the summits using a combination of area surveys and meter plots. Temperature loggers were buried 10 cm in the substrate on each summit aspect and the highest point of the summit area. The loggers recorded temperature at hourly intervals and were replaced every 3-5 years. Nearly continuous temperatures for some loggers were obtained from 2003 through 2018. To better track interannual variability, another band of plots was established below the summit plots in 2010 for Dancing Lady and 2011 for Pitamakin. These were surveyed every year until 2014. A total of 189 species were recorded for the four summit sites. Preliminary results indicated species turnover rates of 0-36% at the five year interval, and 6-55% at the ten year interval. Annual turnover rates for the lower bands on Dancing Lady and Pitamakin were 2-18%. The NE aspects were most species rich and S aspects had the greatest turnover rates. Little difference was evident as a function of elevation. Additional surveys are planned for the summer of 2019.