Article
 

Recovering aspen follow changing elk dynamics in Yellowstone: evidence of a trophic cascade?

Öffentlich Deposited

Herunterladbarer Inhalt

PDF Herunterladen
https://ir.library.oregonstate.edu/concern/articles/r207tr07g

Descriptions

Attribute NameValues
Creator
Abstract
  • To investigate the extent and causes of recent quaking aspen (Populus tremuloides) recruitment in northern Yellowstone National Park, we measured browsing intensity and height of young aspen in 87 randomly selected aspen stands in 2012, and compared our results to similar data collected in 1997–1998. We also examined the relationship between aspen recovery and the distribution of Rocky Mountain elk (Cervus elaphus) and bison (Bison bison) on the Yellowstone northern ungulate winter range, using ungulate fecal pile densities and annual elk count data. In 1998, 90% of young aspen were browsed and none were taller than 200 cm, the height at which aspen begin to escape from elk browsing. In 2012, only 37% in the east and 63% in the west portions of the winter range were browsed, and 65% of stands in the east had young aspen taller than 200 cm. Heights of young aspen were inversely related to browsing intensity, with the least browsing and greatest heights in the eastern portion of the range, corresponding with recent changes in elk density and distribution. In contrast with historical elk distribution (1930s–1990s), the greatest densities of elk recently (2006–2012) have been north of the park boundary (~5 elk/km²), and in the western part of the range (2–4 elk/km²), with relatively few elk in the eastern portion of the range (<2 elk/km²), even in mild winters. This redistribution of elk and decrease in density inside the park, and overall reduction in elk numbers, explain why many aspen stands have begun to recover. Increased predation pressure following the reintroduction of gray wolves (Canis lupus) in 1995–1996 played a role in these changing elk population dynamics, interacting with other influences including increased predation by bears (Ursus spp.), competition with an expanding bison population, and shifting patterns of human land use and hunting outside the park. The resulting new aspen recruitment is evidence of a landscape-scale trophic cascade in which a resurgent large carnivore community, combined with other ecological changes, has benefited aspen through effects on ungulate prey.
  • This is the publisher’s final pdf. The published article is copyrighted by the Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecol.
  • Keywords: Gray wolves, Quaking aspen, Rocky Mountain elk, Populus tremuloides, Bison, Predation risk, Trophic cascade, Cervus elaphus, Yellowstone National Park, Browsing effects, Large carnivore restoration, Canis lupus
  • Keywords: Gray wolves, Quaking aspen, Rocky Mountain elk, Populus tremuloides, Bison, Predation risk, Trophic cascade, Cervus elaphus, Yellowstone National Park, Browsing effects, Large carnivore restoration, Canis lupus
Resource Type
DOI
Date Available
Date Issued
Citation
  • Painter, L. E., Beschta, R. L., Larsen, E. J., & Ripple, W. J. (2015). Recovering aspen follow changing elk dynamics in Yellowstone: evidence of a trophic cascade?. Ecology, 96(1), 252-263. doi:10.1890/14-0712.1
Journal Title
Journal Volume
  • 96
Journal Issue/Number
  • 1
Urheberrechts-Erklärung
Funding Statement (additional comments about funding)
  • We received financial support from the University of Wyoming-National Park Service Research Station.
Publisher
Peer Reviewed
Language
Replaces

Beziehungen

Parents:

This work has no parents.

Artikel