Advancing the Science and Management of Range Shifts
Scientists from the USGS Climate Adaptation Science Centers published a new paper outlining a research agenda for supporting management of species with shifting ranges, including understanding the drivers of range shifts, evaluating management strategies, and improving how science supports decision-making across ecological and jurisdictional boundaries.
A new paper outlines a research agenda for one of today’s most pressing climate adaptation challenges: managing species with shifting ranges.
To track favorable conditions, thousands of plant and animal species have already moved across latitudes, elevations, and depths, or retreated into isolated microrefugia shaped by local habitat. These shifts rarely involve an entire species moving uniformly across the landscape. Instead, ranges often expand in some areas while contracting in others, complicating research hypotheses, analyses, and management strategies.
With contributions from multiple USGS National and Regional CASC authors, the paper, published in Bioscience, synthesizes key knowledge gaps and management challenges and offers a roadmap for future science.
The authors identify three priority research needs: (1) understanding the mechanisms driving range shifts; (2) evaluating the effectiveness of management strategies such as climate refugia, habitat connectivity, and assisted migration; and (3) improving how science informs decision-making, such as when ecological processes cross jurisdictional boundaries.
To illustrate these challenges, the paper includes several case studies, beginning with one that demonstrates how range shifts can defy expectations. The American pika is a small rock-dwelling mammal that is highly sensitive to heat. They can die from brief exposure to temperatures above 25.5 °C, or 78 °F, leading scientists to hypothesize that they would move upslope as temperatures warmed to track cooler temperatures. Instead, pikas have persisted at lower, hotter, elevations in the Columbia River Gorge because the basalt talus slopes (i.e., hillsides covered in rocks) maintain cool underground temperatures year-round, providing natural microrefugia from surface heat. Thick moss mats, forest canopy, and dietary shifts that have reduced the need to forage in the open further buffer the animals from the surrounding heat. Yet, these refuges aren’t without risk; populations remain genetically isolated from the larger pika populations in the Cascades, and their habitat spans a patchwork of federal, state, and private lands – serving as a reminder that even successful climate refuges benefit from coordinated, cross-jurisdictional management.
Other case studies highlight opportunities for range-shift management in practice. Along the California coast, a connected network of marine protected areas has supported numerous fish species and increased growth of individual fish and abundances of fish populations, demonstrating the benefits of habitat connectivity. Another example showcases assisted migration, where conservation partners from the United States, Mexico, and Canada established a breeding population of black-footed albatross on higher ground on Guadalupe Island, Mexico, an island that is more protected from sea-level rise and storm surge than the low-lying islands and atolls in the Northwestern Hawaiian Islands.
Ultimately, the authors argue that advancing range-shift management will require more comprehensive datasets, innovative analyses, stronger cross-jurisdictional partnerships, and decision-making frameworks that explicitly account for uncertainty and multiple stakeholder values.
The full paper, “At the leading edge: Advancing and bridging the science and management of range-shifting species,” is published in the journal Bioscience and was an outcome from a Principal Investigator (PI) workshop for the Climate Adaptation Postdoctoral (CAP) Fellows Program, “Future of Species Range Shifts.”