PARENT SESSION
Oral Session # 32: Herbivory II: Grasslands.
Presiding: K Suttle
Tuesday, August 5. 1:30 PM to 5:00 PM, SITCC Meeting Room 200.
The response of feeding patterns to climatic changes: Generalist herbivores in an annual-dominated California grassland.
Peters, Halton*,1, 2, Mooney, Harold1, Field, Christopher2, 1 Department of Biological Sciences, Stanford, CA2 Carnegie Institution of Washington, Stanford, CA
ABSTRACT- This study explores the influence of future climates on the feeding patterns of generalist herbivores in California annual grassland. Any climate-change induced modification of herbivore feeding tendencies may alter competitive outcomes in plant communities, resulting in shifts in plant species composition. Such modifications include changes in the amount of plant material ingested or in the relative proportions of food plant species consumed. Partly because most studies on plant-herbivore interactions in response to changing climates have used single plant species feeding trials in which host switching was not possible, few data are available on changes in herbivore preferences in response to changing climates. In this study, generalist herbivores (land slugs) were fed leaf material from naturally occurring plant communities that had been grown under one of the following climate change treatments: 1) elevated atmospheric CO2; 2) increased nitrogen deposition; 3) increased precipitation; or 4) increased temperature. Herbivore consumption levels were altered by climate change treatments, with implications for plant and herbivore population sizes in future climates.
Key words: alternative feeding hypothesis, elevated CO2, global climate change, herbivory