Estimating the Impacts of Cumulative Stressors on Fisheries Production in the Chesapeake Bay System with Atlantis

Wednesday, August 20, 2014: 2:10 PM
301A (Centre des congrès de Québec // Québec City Convention Centre)
Thomas F. Ihde , Versar, Inc., NOAA/NMFS Chesapeake Bay Office, Annapolis, MD
Howard M. Townsend , Cooperative Oxford Lab, NOAA/NMFS Chesapeake Bay Office, Oxford, MD
The Chesapeake Bay and its habitats are important for a variety of managed populations, for spawning, nursery-waters, or, for forage. Ultimately, the status of habitats in coastal waters impacts productivity of managed stocks; however, quantifying the connection between these has been elusive. Estimating the effect of any particular system change on production is seldom sufficient because multiple stressors acting simultaneously on a system can produce non-linear, non-intuitive, cumulative change in a system.  Atlantis is a management strategy evaluation tool that integrates current data from multiple disciplines, at multiple scales, and does so within the context of changing system stressors that decision-makers must manage for, like sea level rise, increased development, or decreased eutrophication. 

The Chesapeake system has many stressors that simultaneously affect its habitats. Atlantis models the variable effects of habitat change on managed populations by dynamically simulating the entire system, including habitats themselves (as food, refuge, and sources of chemical cycling) within the context of expected system change.

Current stock assessment focuses on estimating population abundance compared to accepted thresholds, but such efforts seldom consider the effects changing habitat have on productivity. This work begins to fill that gap, providing predictions of productivity under differing assumptions of habitat change.