Fisheries and Global Warming: Impacts on Marine Ecosystems and Food Security
Daniel Pauly, Professor and Director, Fisheries Centre, University of British Columbia
Description: Downward swooping lines on the graphs say it all: The world's fish populations, and hence its fisheries, are collapsing. Daniel Pauly has analyzed reams of data -- including number of boats fishing, their reported catch, the amount of fish thrown overboard -- from every significant fishing area of the world over 50"plus years, and has concluded that today, 30% of our fisheries have crashed, and that by 2048, if the trend continues, most will have disappeared.
This dismal turn of events comes courtesy of rampant over fishing, as well as wantonly wasteful fishing methods, says Pauly. Trawling rigs with miles of bottom"scraping nets may yield tons of desirable table fish, but also tons of byproduct-fish that don't bring as much in the market. These get tossed overboard. In the early 90s, according to Pauly, 30 million tons of fish -- fully 1/4 of the world's catch" -- was discarded. Improvements in technology such as GPS have only made matters worse.
There's little awareness of the magnitude of the problem among Western countries, because there's no sign of it in supermarkets, with fish department displays still spilling over. That's because Europe and America have moved south for their fish, says Pauly. Europe is now plying the waters off Africa, leaving Guinea"Bissau, for instance, with only 7% of its fish. Americans increasingly eat South American and Asian fish. "The only place with no massive depletion is Brunei," says Pauly, because "the Sultan doesn't want boats between his oil wells."
This collapse isn't just a matter for fish eaters. As the top"paying table fish disappear, humans begin "fishing down the marine food web," taking immature fish, and the fish that are prey to other species. Trawling in these already ecologically disturbed waters churns up sediment and takes out bottom dwelling fish, invertebrates and corals, which are essential to a healthy marine system. Biomass disappears, leaving dead zones. These ecosystems are primarily good for jellyfish and harmful algal blooms, says Pauly. The dead zone in the Gulf of Mexico is already the size of the state of Delaware.
Asked what fish it's alright to eat, Pauly recommends chicken. In fact, he doesn't believe "it's an issue that can be fixed by private initiatives." Effective action would mean eliminating fuel and other subsidies from the world's fisheries, and permitting only small scale fisheries that engage in sustainable harvesting. But even this may not save certain species from extinction, as global warming pressures the world's remaining fish species.
About the Speaker(s): Daniel Pauly became a professor at UBC's Fisheries Centre in 1994, after many years at the International Centre for Living Aquatic Resource Management (ICLARM), then in Manila, Philippines. Pauly has authored or co"authored more than 500 scientific articles, book chapters and shorter contributions, and authored, or (co") edited about 30 books and reports. Two books, On the Sex of Fishes and the Gender of Scientist: A Collection of Essays in Fisheries Science (Chapman and Hall, 1994) and "M_thodes pour l'_valuation des ressources halieutiques (C_padu s"Editions, 1997) summarize much previous work, as do his articles "Fishing Down Marine Food Webs" (Science, February 6, 1998), and "Toward Sustainability in World Fisheries," (Nature, August 8, 2002). Two other books, In a Perfect Ocean: Fisheries and Ecosystem in the North Atlantic (Island Press, 2003); and Darwin's Fishes: An Encyclopedia of Ichthyology, Ecology and Evolution (Cambridge University Press, 2004) document his current interests.
In 2001, he was awarded the Murray Newman Award for Excellence in Marine Conservation Research, sponsored by the Vancouver Aquarium, and the Oscar E. Sette Award of the Marine Fisheries Section, American Fisheries Society. He was named a 'Honorarprofessor 'at Kiel University, Germany in late 2002. In 2003, he was named one of UBC's Distinguished University Scholars and elected a Fellow of the Royal Society of Canada (Academy of Science). In 2004, he received the Roger Revelle Medal from IOC/UNESCO, and the Award of Excellence of the American Fisheries Society.
Pauly received his Master (1974), Doctorate (1979) and 'Habilitation' (1985) in Fisheries Biology and Biological Oceanography from the University of Kiel, Germany.
Host(s): School of Science, Center for Global Change Science
It looks like no one has posted a comment yet. You can be the first!
You need to log in, in order to post comments.
More from MIT World — special events and lectures
Added over 5 years ago | 00:59:19 | 4308 views
Added over 5 years ago | 00:58:47 | 4578 views
Added over 5 years ago | 00:56:20 | 10115 views
Added over 5 years ago | 02:44:00 | 4389 views
Added over 5 years ago | 00:26:39 | 6269 views
Added over 5 years ago | 01:04:00 | 13905 views