A brief history of the Newfoundland shelf ecosystem: Exploring the roles of environmental and anthropogenic drivers and their implications for ecosystem-based management

In the Northwest Atlantic Ocean, the Newfoundland shelf ecosystem historically sustained one of the largest Atlantic cod fisheries in the world, but in the late 1980s and early 1990s, many groundfish stocks declined, including the collapse of Northern cod, its most important fishery resource at the time.  This ecosystem changed in  structure from one formerly dominated by groundfish species to one with a major shellfish (northern shrimp) component, which also became the most important fishery in the region after the cod collapse. Together with the decline in groundfishes, capelin, a key forage fish species in this system also experienced dramatic changes in its biology and saw its availability in the region drastically reduced, while seal populations recovered from very low numbers to reach abundances considered similar to the historical highest levels. Many of the most dramatic changes in this ecosystem happened in a period of extreme environmental conditions and significant overfishing. Using dynamic factor analysis, this presentation will investigate some of these issues by exploring the role of environmental and anthropogenic drivers in the trajectories of key fish species in this marine ecosystem, as well as their potential implications for developing and implementing ecosystem-based management approaches.