Monday, August 3, 2020: 3:30 PM-4:00 PM
Co-organizer:
Scott Peacor
The study of predators inducing plastic changes in prey traits and the degree to which these come at a cost in prey fitness (nonconsumptive effect, NCE) and/or indirectly affect resources of the prey on lower trophic levels (trait-mediated indirect effect, TMIE) has gained traction in ecology, management and even public awareness. A commonly made assertion is that a significant component of a predator’s effect in a field scenario comprises risk effects (i.e., NCEs and/or TMIEs). However, a recent comprehensive review challenges this assertion, finding that the majority of studies are in controlled situations, and that very few studies actually demonstrate the importance of predation risk affecting populations in the field. This oral session will address this disconnect between assertion and published findings by presenting a conceptual framework that organizes the distinct methodological approaches being used to examine predation risk effects in the field. To promote synthesis, the organized oral session will highlight the distinct components involved in the process of predation risk causing NCEs and TMIEs, which will help address the inconsistent use of terminology that hinders cross-system generalities. Speakers in this proposed session are currently studying species from marine, freshwater and terrestrial systems, with animals ranging from crustaceans to large mammals. They have faced the challenges of examining the influence of predation risk on field patterns. In their presentations, speakers will share their methodological approach and research results with reference to the conceptual framework of methodology and terminology. A common theme will be the speaker’s suggestions on what is needed and how to proceed towards making ecology a more predictive discipline by taking research about predation risk effects into the field. The current debate of the influence of wolves on the Yellowstone ecosystem highlights the relevance of developing frameworks and methodologies to scale up from experiments on predation risk effects to field patterns.
4:30 PM
Can disease transform a trait-mediated system to a density-mediated one? Ecosystem responses to the collapse of vicuñas in the high Andes
Justine Smith, University of California, Davis;
Julia Monk, Yale University;
Emiliano Donadio, Rewildling Argentina;
Paula L. Perrig, University of Wisconsin-Madison;
Jonathan N. Pauli, University of Wisconsin-Madison;
Owen R. Bidder, University of California, Berkeley;
Oswald J. Schmitz, Yale University;
Arthur D. Middleton, University of California - Berkeley