Abstract
<jats:p>Climate change has likely shaped the size and distribution of alpine plant communities across North America since the ice sheet retreat around 13,000 yrs BP, but modern-day drivers of alpine plant distributions across this region have been understudied. Meanwhile, their role as popular recreational destinations makes them susceptible to trampling and other human-mediated disturbance. We applied an island biogeography framework to the island-like remnants of alpine habitat in the northeastern U.S. and tested the influence of size and connectivity on alpine specialist species richness. We completed plant community surveys consisting of 50 m transects and 1 m² plots across 8 alpine zones in the northeastern United States to assess vascular plant species richness and cover. We also assessed the area of each alpine zone, along with connectivity amongst alpine communities. We then analyzed data from the hiking app AllTrails to estimate recreational visitation at each of our sites. We used a generalized linear model to assess the relationships between species richness, island biogeography metrics, and hiker visitation rates, and multiple linear regressions to assess the relative importance of our explanatory variables. Connectivity among sites, number of hikes completed, and area were the strongest predictors of alpine specialist plant species richness across our sites. Also, distance to nearest thru-hiking trail was negatively correlated with species richness, meaning peaks with summit accessibility via popular trails also had higher species richness. Alpine plant richness in northeast alpine zones is influenced by island biogeography’s key features, including area of the islands and connectivity between islands, along with conservation and management histories relating to recreational visitation. Recreational visitation is not negatively impacting species richness, which could be because the alpine zones with the most visitors are also those with longstanding conservation built around biodiverse communities.</jats:p>