Spatial Dynamics of Valued Atlantic Groundfish

OFI Large Research Module D

Using acoustic fish tags and genetic markers, researchers are tracking the movements of Northern cod and Atlantic halibut to identify where and when they spawn, feed, and migrate. The data collected through this research project will help characterize fish populations (stocks and sub-stocks), survival, spawning, movements, and track their distribution in the Northwest Atlantic Ocean. This research on groundfish (fish that live and feed near the bottom of the ocean) will support the development of new, more responsive, sustainable fisheries management practices.  

About the research

Northern cod and Atlantic halibut are both high-valued fish species. To varying degrees, climate change, environmental stresses, and intense fishing have affected their distributions. Marine species are relocating in response to climate change in particular, thus shifting the entire ecosystem. The fish population information produced by this research will support sustainable management of recovering cod stocks (following fisheries collapses in the early 1990s) and high-valued halibut stocks.  

Key research questions:

• Stock Structure: How many stocks and sub-stocks exist, how are they distributed, and how are they connected?  
• Spawning Grounds: How many major spawning groups of stocks and sub-stocks occur and where?  
• Migration Patterns: Do stocks follow predictable patterns of movement and when do such movements occur? Does movement vary depending on fish size?  
• Demography: What are the rates of residency, survival, and emigration?  
• Sustainability: How can improved information about stock locations and movements advance stock assessment computer models?  
• Trust: How does improved understanding of stocks and their locations and movements impact consumer confidence in the legitimacy of independent fisheries certifications?  

This research will support new conservation and management strategies that consider how ecosystems may change in the future, based on three key aspects:

Tracking

• Track animals to locate spawning areas, which can help define sub-stock
• Identify annual migrations among seasonal habitats
• Link where animals occur to genetic data collected when they were tagged

Genetics

• Develop genetic markers to differentiate between stocks identified by electronic tracking  

Social Sciences

• Study the social and economic consequences of improved stock information on how society uses fish and fisheries

The research team

Module Leads:

• Sara Iverson, Scientific Director at the Ocean Tracking Network (Dalhousie)
• Aaron MacNeil, Canada Research Chair in Fisheries Ecology (Dalhousie)
• Jonathan Fisher (Memorial)

Primary Collaborating Researchers:

Dalhousie University:

• Damian Lidgard, Emerging Researcher
• Fred Whoriskey
• Paul Bentzen
• Daniel Ruzzante
• Megan Bailey

Memorial University of Newfoundland:

• Arnault Le Bris, Emerging Researcher

Fisheries and Oceans Canada:

• Nell den Heyer
• Robert Gregory
• Ian Bradbury

Additional Collaborating Researchers:

Dalhousie University:

• Richard Davis

Fisheries and Oceans Canada:

• John Brattey
• Jae Choi
• Derek Fenton
• Corey Morris
• Nancy Shackell

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Caught on camera: ancient Greenland sharks

The Greenland shark is one of the world’s largest marine species, reaching lengths of over six metres. And yet these fish, which prefer the deep, cold waters of the Arctic and North Atlantic oceans, have largely eluded scientific study. However, OFI researcher, Jonathan Fisher was part of a team that captured underwater video footage of Greenland sharks in the Canadian Arctic, providing valuable insight into their abundance, size and behaviour, as well as their distribution.

Learn more by reading an article co-written by Dr. Fisher and PhD student researcher, Brynn Devine of Memorial University in Conversation Canada.

Developing new approaches to fisheries management

According to OFI researcher, Aaron MacNeil, Canadian fisheries operate with little formal input from fishers and other stakeholders. But social and cultural factors that affect how and why people fish directly impact sustainability.

“My experience speaking with fishers here in Nova Scotia has been remarkably similar to those in places like Australia or Kenya,” says Dr. MacNeil.

“It is incredible how consistent fishers are in terms of how they see themselves and the strong sense of identity they have with their work. Unfortunately, most fishers are also facing similar threats to their livelihoods from pollution, overfishing, and climate change. By studying how others have dealt with these problems, we can develop a range of strategies for Canadian fishers and policy makers to help confront these problems in the future.”

Dr. MacNeil is aiming to develop a new approach to fisheries management for Canada that incorporates social and economic factors and considers the needs of the fishers balanced with the total catch.

Researchers recognized

• Royal researcher - In September 2018, the Royal Society of Canada recognized OFI researcher Sara Iverson for her outstanding scholarly and scientific achievements. Learn more.
• ‍Aaron MacNeil, an OFI researcher and associate professor from Dalhousie University’s Department of Biology, has been appointed as a Canada Research Chair by the Government of Canada. Established 17 years ago, the Canada Research Chairs program supports and attracts the world’s best researchers in the fields of engineering and the natural sciences, health sciences, humanities and social sciences. In addition to conducting research that improves our depth of knowledge and quality of life, chair holders also train the next generation of leaders in their fields through student supervision and teaching.

Save coral reefs: eradicate rats

OFI researcher Aaron MacNeil, along with his scientific colleagues, has discovered that rats are responsible for damaging coral reefs. Their study, published in the journal Nature, concludes that rat control should be an urgent conservation priority on many remote tropical islands.

“Eliminating the rats that infest these islands would benefit terrestrial ecosystems and enhance coral reef productivity and function,” says Dr. MacNeil.

“It could tip the balance for the future survival of these reefs and their ecosystems.”