WWF-Canada Blog:
Climate


Canadian ocean economies at risk from GHG emissions

By Rashid Sumaila
Director, Fisheries Centre & Fisheries Economics Research Unit, UBC

Beyond playing a crucial role in marine ecosystems, fish support human well-being through employment in fishing, processing, and retail services, as well as food security for many coastal regions. Gross revenues from ocean fisheries worldwide are estimated at about US$85 billion annually, generating economic and household income impacts throughout the world economy of about US$240 billion and US$63 billion annually. The equivalent numbers for Canada are US$2.8 billion, US$9.1 billion and US$2.9 billion. In addition to these commercial values, fish is a good source of protein, micro-nutrients, minerals and essential fatty acids, and globally provides 3 billion people up to 15 per cent of their dietary animal protein needs. In Canada, many coastal communities, especially First Nations groups, rely heavily on fish for food and employment, in addition to their cultural and ceremonial importance.

Ensuring that our oceans and fish stocks are healthy and sustainable long-term is important to the Canadian and global economy and identity. Achieving healthy oceans has always been difficult, as they are plagued by the historical problems of overfishing, pollution, and habitat destruction and loss. Global warming, ocean acidification and deoxygenating are new threats. Combined with the longstanding threats, these new issues are creating formidable challenges to this important animal protein source, and the economics of the businesses and communities that depend on them. As amply demonstrated by the collapse of northern cod off Newfoundland, the depletion of fish stocks can have devastating effects on human well-being.

Recently, the ocean has become warmer, with an increase in average temperature of 0.2oC at the top 300 metres of the ocean between the 1950s and 1990s. As the ocean warms, not only will the sea ice extent in the Arctic and other areas of the world continue to decrease, but the pH of surface ocean waters will also decrease, making it more acidic and less oxygenated, resulting in changes in productivity of the living resources contained in them.
Changes in temperature and ocean chemistry directly affect the physiology, growth and reproduction of marine fish species. For example, fishes in warmer temperatures are expected to have a smaller maximum body size and smaller size at first maturity. Fish with smaller bodies that live in warmer environments are expected to suffer higher natural mortality rates. Current studies suggest that species’ responses to more acidic water may vary between species, with invertebrates such as shell fish, currently important to Canadian fisheries, impacted more while the effect on finfish is more uncertain.

Given the predicted biophysical and ecological effects of the new threats, they will affect the economics of fishing because both the quantity and quality of marine fish catch would be impacted, through changes in: price and value of fish catch; fishing costs; fishers’ incomes; earnings to fishing companies; resource rent (i.e., the surplus after all costs, including ‘normal’ profits, have been covered); and economic impacts throughout the economy. For example, during the 1997/98 El Niño, Chilean and Peruvian pelagic marine landings declined by about 50 per cent, resulting in a drop in fishmeal export values by about USD 8.2 billion. This huge drop generated negative economic effects and caused severe hardship (e.g. lost jobs, incomes and earnings) in the two countries.
To tackle these new threats to our oceans, we need to fill existing knowledge gaps that prevent a comprehensive understanding of the full range of impacts that ocean warming could have on the economics of fisheries. Given that climate change is already affecting fisheries, it is important for both public and private stakeholders to help fisheries address the new threats. Maintaining more abundant populations is a way to increase their capacity to adapt to environmental change. Hence, solving the overfishing problem is fundamental. Governments have generally been reactive rather than anticipatory in their response to declining fishing opportunities, with huge economic consequences. Given the scale of the anticipated effects of ocean warming on fisheries, reactive measures are likely to be very costly.

Reducing greenhouse gas emissions would substantially diminish the ecological impacts of ocean warming on fish stocks and thus minimize its economic effects. Also, the cost of adapting to the new threats would be lower with reduced emissions. Thus, it is important for all with interests in the health of our oceans to push for lower greenhouse emissions.

On Tuesday November 27 at 12:00, Dr. Sumaila will be presenting at the ‘Oceans on the Hill’ speakers series hosted by WWF and the All Party Ocean Caucus (Parliament Hill, Room 216-N Centre Block). For more information, contact: adumbrille@wwfcanada.org