B IOLOGY S EMINAR
PROMOTION LECTURE
4:00 PM S E M I N A R
H I T C H C O C K H A L L 132
R E F R E S H M E N T S I N F O Y E R 3:45 PM
AND FOLLOWING SEMINAR
Tuesday, October 18, 2011
“Effects of Multiple Stressors in an
Estuarine Ecological Network”
Dr. Jennifer
Ruesink
Associate Professor
Department of Biology
University of Washington
In ecological networks, several factors contribute to the difficulty of predicting system response to
perturbations, particularly because the strength of particular connections can be sensitive to the density of
interactors and the context within which they are embedded. Further, when multiple stressors act
simultaneously, their aggregate effect may be additive, antagonistic (less than the sum of parts) or
synergistic (more than the sum of parts). Estuarine ecosystems provide numerous human benefits
through their productivity for aquaculture and fisheries but are also under threat. These threats derive
both from land, due to the burden of human population along the coast, and from regional climate change
altering atmospheric and coastal ocean characteristics. I will illustrate these points with two examples
testing hypotheses about drivers of distribution and abundance of estuarine habitat-forming species in the
field. First, based on experimental manipulations, seagrass showed mostly additive or antagonistic
responses to perturbations such as damage, removal, nutrients, and non-native species. Second, based on
surveys and historical reconstruction, oysters demonstrated strong system-wide variation in recruitment
associated with temperature but appeared to overcome locally-acidified water conditions. Washington
state leads the U.S. in shellfish production and maintains seagrass despite global declines reaching crisis
status. This research indicates resilient responses to high-impact stressors help maintain estuarine
productivity but at the same time - due to nonlinearities and potential synergisms - leaves open the
question of performance in the face of new environmental threats.
Host: H.D. “Toby” Bradshaw
To request disability accommodations, contact the Disability Services Office at least 10 days in advance of the event.
206-543-6450 OR dso@u.washington.edu