Uncertainty and natural variability in the ecological footprint of fisheries: A case study of reduction fisheries for meal and oil

Abstract It is well understood that measurements of ecological footprint and many other ecological indicators are associated with varying degrees of uncertainty, yet imprecision in ecological footprint results is rarely assessed or communicated. We calculated the marine portion of the ecological footprint of products derived from five reduction fisheries: Peruvian anchovy (Engraulis ringens), Atlantic herring (Clupea harengus), Gulf menhaden (Brevoortia patronus), blue whiting (Micromesistius poutassou) and Antarctic krill (Euphausia superba). Monte Carlo analysis was used to measure the imprecision in marine footprint measurements resulting from multiple sources of uncertainty and natural variability in input parameters, and to determine the degree to which imprecision affects our ability to draw meaningful conclusions when comparing products sourced from different fisheries on the basis of ecological footprint. Gulf menhaden and Antarctic krill were found to have the smallest marine footprints, while blue whiting was found to have the largest. Results show that there is much uncertainty associated with marine footprint calculations and that the most significant drivers of this imprecision are uncertainty and natural variability regarding measurements of trophic level and trophic interactions. Marine footprint is highly correlated with trophic level, and clear differences can be seen when comparing species of very different trophic levels. However, comparisons of products derived from species’ with similar trophic levels are less likely to provide conclusive results. The choice of mass, protein or energy content as the basis of comparison was also considered and was found to influence the results, particularly when comparing species with similar trophic levels. While it is likely that imprecision of marine footprint measurements of fishery-derived products will remain high, technological improvements and a better understanding of marine ecosystem dynamics may make future studies more precise.

[1]  Mathis Wackernagel,et al.  Ecological Footprints and Appropriated Carrying Capacity: Measuring the Natural Capital Requirements of the Human Economy. , 1996 .

[2]  E. Odum,et al.  Ecology and Our Endangered Life-Support Systems , 1989 .

[3]  I. Joint,et al.  Estimation of phytoplankton production from space: current status and future potential of satellite remote sensing. , 2000, Journal of experimental marine biology and ecology.

[4]  Guillaume Péron,et al.  Where do fishmeal and fish oil products come from? An analysis of the conversion ratios in the global fishmeal industry , 2010 .

[5]  Carl Folke,et al.  Analysis Managing aquaculture for sustainability in tropical Lake Kariba, Zimbabwe , 1996 .

[6]  Harald Ellingsen,et al.  Energy consumption in the Norwegian fisheries , 2009 .

[7]  B. Mattsson,et al.  Life Cycle assessment of frozen cod fillets including fishery-specific environmental impacts , 2003 .

[8]  Peter Tyedmers,et al.  Salmon and sustainability : the biophysical cost of producing salmon through the commercial salmon fishery and the intensive salmon culture industry , 2000 .

[9]  J. Talberth,et al.  Refining the ecological footprint , 2008 .

[10]  J. Lamarque,et al.  Global Biodiversity: Indicators of Recent Declines , 2010, Science.

[11]  Gene Bazan Our Ecological Footprint: Reducing Human Impact on the Earth , 1997 .

[12]  D. Pauly,et al.  Primary production required to sustain global fisheries , 1995, Nature.

[13]  Carl Folke,et al.  Energy economy of salmon aquaculture in the Baltic sea , 1988 .

[14]  Malcolm James Beynon,et al.  Considering the effects of imprecision and uncertainty in ecological footprint estimation: An approach in a fuzzy environment , 2008 .

[15]  M. Metian,et al.  Global overview on the use of fish meal and fish oil in industrially compounded aquafeeds: Trends and future prospects , 2008 .

[16]  Raymond L. Lindeman The trophic-dynamic aspect of ecology , 1942 .

[17]  Carl Folke,et al.  Ecological limitations and appropriation of ecosystem support by shrimp farming in Colombia , 1994 .

[18]  Eva Roth,et al.  A discussion of the use of the sustainability index: 'ecological footprint' for aquaculture production , 2001 .

[19]  H. V. D. van der Werf,et al.  Environmental Impact Assessment of Salmonid Feeds Using Life Cycle Assessment (LCA) , 2004, Ambio.

[20]  Carl J. Walters,et al.  Ecopath, Ecosim, and Ecospace as tools for evaluating ecosystem impact of fisheries , 2000 .

[21]  V. Braithwaite,et al.  Trophic Structure and Community Stability in an Overfished Ecosystem , 2010, Science.

[22]  Kung-Sik Chan,et al.  Ecological Effects of Climate Fluctuations , 2002, Science.

[23]  Robert Costanza,et al.  Investing in natural capital , 1993 .

[24]  Claudia Pahl-Wostl,et al.  Toward a Relational Concept of Uncertainty: about Knowing Too Little, Knowing Too Differently, and Accepting Not to Know , 2008 .

[25]  Per-Anders Hansson,et al.  Uncertainties in the carbon footprint of food products: a case study on table potatoes , 2010 .

[26]  Daniel D. Benetti,et al.  From Fishing to the Sustainable Farming of Carnivorous Marine Finfish , 2010 .

[27]  A. Hospido,et al.  Life cycle environmental impacts of Spanish tuna fisheries , 2005 .

[28]  A. Ponter,et al.  Tables of composition and nutritional value of feed materials: pigs, poultry, cattle, sheep, goats, rabbits, horses and fish. , 2004 .

[29]  Carl Folke,et al.  The role of ecosystems for a sustainable development of aquaculture , 1989 .

[30]  Peter Tyedmers,et al.  Fisheries and Energy Use , 2004 .

[31]  J. Aubin,et al.  Characterisation of the environmental impact of a turbot (Scophthalmus maximus) re-circulating production system using Life Cycle Assessment , 2006 .

[32]  Mathis Wackernagel,et al.  EVALUATING THE USE OF NATURAL CAPITAL WITH THE ECOLOGICAL FOOTPRINT : APPLICATIONS IN SWEDEN AND SUBREGIONS , 1999 .

[33]  U. Sonesson,et al.  Not all salmon are created equal: life cycle assessment (LCA) of global salmon farming systems. , 2009, Environmental science & technology.

[34]  Stefanie Hellweg,et al.  Ecological footprint accounting in the life cycle assessment of products , 2008 .

[35]  D. Cushing Marine ecology and fisheries , 1975, Environmental Biology of Fishes.

[36]  P. Tyedmers,et al.  Fuel use and greenhouse gas emission implications of fisheries management: the case of the new england atlantic herring fishery , 2010 .

[37]  R. Scholes,et al.  Ecosystems and human well-being: current state and trends , 2005 .

[38]  J. Randers,et al.  Tracking the ecological overshoot of the human economy , 2002, Proceedings of the National Academy of Sciences of the United States of America.

[39]  Claudia Pahl-Wostl,et al.  Towards a relational concept of uncertainty in adaptive water management: about knowing too little, knowing too differently, and accepting not to know: Paper presented at the 14th International Conference on Multi-Organizational Partnerships, Alliances and Networks , 2007 .

[40]  Mikkel Thrane,et al.  Energy Consumption in the Danish Fishery: Identification of Key Factors , 2004 .

[41]  Manfred Lenzen,et al.  UNCERTAINTY ANALYSIS FOR MULTI-REGION INPUT–OUTPUT MODELS – A CASE STUDY OF THE UK'S CARBON FOOTPRINT , 2010 .

[42]  T. Platt,et al.  An estimate of global primary production in the ocean from satellite radiometer data , 1995 .

[43]  Trevor Platt,et al.  Regionally and seasonally differentiated primary production in the North Atlantic , 1995 .

[44]  W. Walker,et al.  Defining Uncertainty: A Conceptual Basis for Uncertainty Management in Model-Based Decision Support , 2003 .

[45]  Jeroen B. Guinée,et al.  Uncertainties in a carbon footprint model for detergents; quantifying the confidence in a comparative result , 2009 .

[46]  William E. Rees,et al.  Ecological footprints and appropriated carrying capacity: what urban economics leaves out , 1992 .

[47]  Albert G. J. Tacon,et al.  STATE OF INFORMATION ON SALMON AQUACULTURE FEED AND THE ENVIRONMENT , 2005 .

[48]  F. Chavez,et al.  Biological Consequences of El Ni�o , 1983, Science.

[49]  R. Parker,et al.  MEASURING AND CHARACTERIZING THE ECOLOGICAL FOOTPRINT AND LIFE CYCLE ENVIRONMENTAL COSTS OF ANTARCTIC KRILL (EUPHAUSIA SUPERBA) PRODUCTS , 2011 .

[50]  Pamela A. Matson,et al.  HUMAN APPROPRIATION OF THE PRODUCTS OF PHOTOSYNTHESIS , 1986 .

[51]  R. R. Strathmann,et al.  ESTIMATING THE ORGANIC CARBON CONTENT OF PHYTOPLANKTON FROM CELL VOLUME OR PLASMA VOLUME1 , 1967 .