I. ATLANTIC ARENA: THEMES 1–4

I.1 INTEGRATED INTERDISCIPLINARY OBSERVING AND MODELING PLATFORM

Leaders: Katja Fennel (Dalhousie U), Jinyu Sheng (Dalhousie U), Peter Smith (DFO-BIO, Dalhousie U)

Co-PIs: John Cullen (Dalhousie U), Christopher Taggart (Dalhousie U), Keith Thompson (Dalhousie U)

Collaborators: Blair Greenan (DFO-BIO)

Summary

Understanding the integrated functioning of ocean ecosystems lies at the heart of all OTN research. Point measurements of the passage of tagged animals across fixed lines of underwater acoustic receivers must be interpreted in the context of physical, biological, and chemical ocean characteristics. A major challenge faced by OTN studies is the synthesis of its physical, biological, and chemical measurements, along with other available data streams, to generate a dynamically consistent, time-varying, three-dimensional view of the ocean that can be used to explain and predict the observed movements of marine animals, and thus answer the fundamental questions asked by OTN Canada. In this project our goal is to develop a general purpose, observation and modeling platform that will provide integrated simulations of the marine environment and the movement of marine animals. This will be done by supplementing existing observational capabilities (within OTN and other sustained monitoring programs) with new observation tools, advanced physical, biological, and chemical models, and effective methods for combining the models with observations (data assimilation)—all applied in the context of decades of oceanographic and fisheries research.

Atlantic Arena Photos

Projects

  • I.1.1 Advanced Observing Component
    Investigators: J. Cullen, C. Taggart, P. Smith, B. Greenan
  • I.1.2 Integrated Physical and Biological Modeling Component
    Investigators: J. Sheng, K. Fennel, K. Thompson, J. Cullen, P. Smith, B. Greenan
  • I.1.3 Data Assimilation Component
    Investigators: K. Thompson, J. Sheng, K. Fennel, J. Cullen

I.2 MIGRATORY MARINE LIVING RESOURCES AND TROPHIC INTERACTIONS

Leaders: Sara Iverson (Dalhousie U), Ian Fleming (Memorial U), Don Bowen (DFO-BIO, Dalhousie U)

Co-PIs: Martin Castonguay (DFO-IML, Laval U), Michael Dadswell (Acadia U), Julian Dodson (U Laval), Joanna Mills Flemming (Dalhousie U), Bruce Hatcher (Cape Breton U), Matthew Litvak (Mount Allison U), Mike Stokesbury (Acadia U)

Collaborators: Ian Jonsen (Dalhousie U), Frederick Whoriskey (Dalhousie U)

Summary

Most sea animals make extensive movements through the ocean, ranging from simple drifting or foraging patterns to extensive annual migrations. For instance, many fish migrate over daily to annual periods and over spatial scales extending up to thousands of kilometers. These migrations may be driven by factors such as reproductive requirements or diet, but in many cases the causes are unknown. Understanding these movements and migrations, and the physical conditions that drive them, is crucial to conservation, economic development and predictions of how patterns will alter with prospective climate change and variability. Diadromous fish are of particular interest as they travel between fresh and salt water, often over extensive ranges. In general, anadromous fish (e.g., salmon) breed in fresh water but migrate to the ocean, whereas catadromous fish (e.g., freshwater eels) breed in the ocean but live mostly in fresh water. Thus, especially for species of conservation concern, it is difficult to discern where the greatest pressures on their populations lie. Of equal importance, is understanding the movements of the predators of such prey, their interactions with lower trophic levels, and the potential impacts of predation on prey populations. Additionally, since top predators can be used as indicators of prey populations and serve to integrate the cumulative effects of ecosystem changes, they can be used as ocean samplers themselves. The main objectives of this portion of the Atlantic program are 1) to target migratory species that represent model or keystone species for their ecosystems and that include key species at risk, in order to clarify their movements and population structure in relation to oceanographic features and variability; and 2) to better understand predator and prey distribution in time and space in relation to ocean characteristics and to test hypotheses concerning predator and other impacts on prey populations, including important commercial fish stocks.

Atlantic Arena Photos

Projects