Forestry Hanover Seminar Series presents: John Vucetich, Michigan Technological University

Date: March 24, 2015
Location: 225 Natural Resources

Time: 4 p.m. (Refreshments at 3:50 p.m.)

Forestry Hanover Seminar Series presents:

Laws of nature, historical contingency, and the wolves and moose on Isle Royale

Presented by:

John Vucetich
School of Forest Resources and Environmental Science
Michigan Technological University


A central purpose of ecology is to explain how and why ecological communities fluctuate in abundance over time. One basic explanation is that fluctuations are determined by predictable laws of nature. A competing, antithetical explanation is that fluctuations are explained by inherently unpredictable historical contingencies, events such as extreme weather or novel diseases. Understanding the relative importance of those two explanations has been stymied for decades by an inability to compare those explanations in a quantifiable framework.

We developed a framework, described in a recently funded NSF proposal, that can evaluate the extent to which population fluctuations can be explained by a series of random events characterized by legacy effects that are comparable in length to the waiting time between such events, and the disparate nature of individual events in the series. The framework involves building statistical models based on first principles of predator-prey theory and comparing those laws-of-nature models to statistical models accounting only for the influence of a few major historically contingent events (i.e., novel disease, severe winter, a genetic rescue event, and any other event that might occur during the study period). The analytical framework is a synthesis of several important phenomena in ecology – reddened spectra, weak density dependence, tipping points, legacy effects, and ecological surprises.  We apply this framework to the wolf-moose-forest food chain on Isle Royale National Park.

The wolves of Isle Royale have also become the focus of broad public concern with respect to understanding how protected areas should be managed in the face of climate change. A forthcoming decision about the management of Isle Royale wolves is expected to set precedence for many protected areas. I will also present an update of the ecology and policy status of this issue.