Indicator 1.07: number and geographic distribution of forest-associated species at risk of losing genetic variation and locally adapted genotypes, 2003-2014

Abstract

This indicator provides information on the number and distribution of forest-associated species and infraspecies (e.g., subspecies, varieties) at risk of losing genetic variation across their geographic range. Comparing current geographic distributions with historical distributions is the basis for identifying the species and infraspecies whose range has contracted significantly (based on per-State presence and absence). Human activities, like land use conversions, climate change, the alteration of native habitats, the introduction of exotic species, and direct exploitation, are accelerating changes in species distributions. The size of a distribution is often related to the number of genetically distinct populations that exist. Consequently, species and infraspecies that currently occupy a smaller portion of their former distribution signal a potential loss of their genetic variation. This erosion in genetic variation makes species less adaptable to environmental change, increases the risk of extinction, and lowers the overall resilience of forest ecosystems.

Citation

Nelson, Mark D. 2026. Indicator 1.07: number and geographic distribution of forest-associated species at risk of losing genetic variation and locally adapted genotypes, 2003-2014. FS-Indicator-1.07-2030. Washington, DC: U.S. Department of Agriculture, Forest Service. 5 p. https://doi.org/10.2737/FS-Indicator-1.07-2030.