State of the Pacific Ocean 2008

The 2008 State of the Pacific Ocean Report by Fisheries and Oceans Canada (DFO) highlights notable changes in atmospheric and oceanic conditions, which have the potential to affect resident and migratory fish and other marine populations in British Columbia.

Highlights for 2008

Coolest oceans in 50 years in the Pacific Northeast

• Although ocean conditions globally were generally warm, waters off the Pacific coast of Canada were the coldest observed in 50 years, and the cooling extended far into the Pacific Ocean and south along the American coast. Near-shore temperatures dropped as well, as did temperatures in deep waters of the Strait of Georgia. Only the surface temperatures in the Strait of Georgia remained at or above normal. This cooling is associated with weather patterns typical of La Niña, and of the local cold phase of the Pacific Decadal Oscillation (PDO).

Spreading hypoxia in deep waters along the West Coast

• Oxygen levels are declining in West Coast waters 100 to 500 metres below the ocean surface, based on time-series measurements obtained over 25 years in the open ocean and along the Pacific coast up into northern British Columbia. Oxygen concentrations in bottom waters of the B.C. continental shelf dropped markedly in 2008, compared to 2006. Along the Oregon coast, low oxygen events have caused fish and crab kills at the ocean bottom during the last several years, events that were not observed in the previous century.

Shrimp and flatfish species in recovery, sardine and herring populations are down

• Herring abundance on the West Coast of Vancouver Island is at a historically low level, and generally low elsewhere off the B.C. coast. Warming ocean conditions in 2003 to 2005, resulting in increased hake abundance in this area, may be expected to negatively affect herring recruitment and stock abundance over the short term.
  
• Warm ocean conditions in 2004 to 2005 have resulted in widespread distribution of sardines throughout southern Hecate Strait and Queen Charlotte Sound.
  
• Smooth Pink Shrimp bottom trawl surveys in 2008 found that the abundance of smooth pink shrimp off central Vancouver Island has increased from very low levels observed during 2004-2007. This population may be beginning to recover after undergoing declines as a result of warm conditions during the mid-decade.
  
• The biomass of certain marine species, including spiny dogfish, English sole and Pacific hake, also increased in 2008 after declines in 2006 and 2007.
  

Improved survivals for seabirds, sablefish, and juvenile salmon, but variable salmon returns expected

• Almost 30 years of regular sampling of zooplankton off Vancouver Island has made it possible for scientists to use this information to predict survival rates for various key marine species further up the food chain. Zooplankton measurements in 2008 imply relatively high survival rates for several marine species, including some salmon and sablefish in southern BC, and seabirds on Triangle Island.
  
• With the cool conditions of 2007-2008, and some observations of increased numbers of juvenile sockeye along the West Coast of Vancouver Island, DFO anticipates increased marine survival that will lead to a period of stock rebuilding for many sockeye returning in 2009-2010, and most southern B.C. coho returning in 2009, with the exception of those returning to Strait of Georgia streams.

This is the tenth annual report by members of the Fisheries and Oceanography Working Group (FOWG) of DFO’s Pacific Centre for Science Advice, Fisheries and Oceans Canada (DFO). DFO scientists provide advice about fish stocks and habitat status as well as the potential biological consequences of fisheries management actions and natural events. The FOWG is responsible for reviewing and evaluating scientific information on the status of living aquatic resources and their ecosystems, and on biological aspects of stock management. Its findings contribute to DFO’s management of fisheries and marine resources in Pacific region, and to science-based decision-making in the Department.

Fisheries and Oceans Canada researchers develop and implement scientific surveys, data collection techniques, basic and applied research, scientific predictions and forecasts, as well as the publication of scientific results.

Annual Pacific Region State of the Ocean Reports

For information;
Diane Lake
604-666-0939