Climate and land-use change are the major drivers of global biodiversity loss. Their effects are particularly acute for wide-ranging consumers, but little is known about how these factors interact to affect the abundance of large carnivores and their herbivore prey. We analyzed population densities of a primary and secondary consumer (mule deer, Odocoileus hemionus, and mountain lion, Puma concolor) across a climatic gradient in western North America by combining satellite-based maps of plant productivity with estimates of animal abundance and foraging area derived from Global Positioning Systems telemetry data (GPS). Mule deer density exhibited a positive, linear relationship with plant productivity (r2 = 0.58), varying by a factor of 18 across the climate-vegetation gradient (range: 38–697 individuals/100 km2). Mountain lion home range size decreased in response to increasing primary productivity and consequent changes in the abundance of their herbivore prey (range: 20–450 km2). This pattern resulted in a strong, positive association between plant productivity and mountain lion density (r2 = 0.67). Despite varying densities, the ratio of prey to predator remained constant across the climatic gradient (mean ± SE = 363 ± 29 mule deer/mountain lion), suggesting that the determinacy of the effect of primary productivity on consumer density was conserved across trophic levels. As droughts and longer term climate changes reduce the suitability of marginal habitats, consumer home ranges will expand in order for individuals to meet basic nutritional requirements. These changes portend decreases in the abundance of large-bodied, wide-ranging wildlife through climatically driven reductions in carrying capacity, as well as increased human–wildlife interactions stemming from anthropogenic land use and habitat fragmentation. Published 2018. This article is a U.S. Government work and is a public domain in USA.
Department of Wildland Resources, Utah State University, Logan, UT, United States; Global Land Cover Facility, Department of Geographical Sciences, University of Maryland, College Park, MD, United States; terraPulse, Inc., North Potomac, MD, United States; School of Life Sciences, University of Nevada, Las Vegas, NV, United States; Utah Division of Wildlife Resources, Salt Lake City, UT, United States; U.S. Geological Survey, Southwest Biological Science Center, Flagstaff, AZ, United States; U.S. Geological Survey, Western Ecological Research Center, Las Vegas Field Station, Henderson, NV, United States; U.S. Geological Survey, Utah Cooperative Fish and Wildlife Research Unit, Quinney College of Natural Resources, Utah State University, Logan, UT, United States
Recommended Citation:
Stoner D.C.,Sexton J.O.,Choate D.M.,et al. Climatically driven changes in primary production propagate through trophic levels[J]. Global Change Biology,2018-01-01,24(10)