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Perceptions of trends in Seychelles artisanal trap fisheries: comparing catch monitoring, underwater visual census and fishers' knowledge

  • TIM M. DAW (a1) (a2), JAN ROBINSON (a3) and NICHOLAS A. J. GRAHAM (a2) (a4)

Fisheries scientists and managers are increasingly engaging with fishers’ knowledge (FK) to provide novel information and improve the legitimacy of fisheries governance. Disputes between the perceptions of fishers and scientists can generate conflicts for governance, but can also be a source of new perspectives or understandings. This paper compares artisanal trap fishers’ reported current catch rates with landings data and underwater visual census (UVC). Fishers’ reports of contemporary ‘normal’ catch per day tended to be higher than recent median landings records. However, fishers’ reports of ‘normal’ catch per trap were not significantly different from the median CPUE calculated from landings data, and reports of ‘good’ and ‘poor’ catch rates were indicative of variability observed in landings data. FK, landings and UVC data all gave different perspectives of trends over a ten-year period. Fishers’ perceptions indicated greater declines than statistical models fitted to landings data, while UVC evidence for trends varied between sites and according to the fish assemblage considered. Divergence in trend perceptions may have resulted from differences in the spatial, temporal or taxonomic focus of each dataset. Fishers may have experienced and understood behavioural changes and increased fishing power, which may have obscured declines from landings data. Various psychological factors affect memory and recall, and may have affected these memory-based estimates of trends, while different assumptions underlying the analysis of both interview data and conventional scientific data could also have led to qualitatively different trend perceptions. Differing perspectives from these three data sources illustrate both the potential for ‘cognitive conflicts’ between stakeholders who do not rely on the same data sources, as well as the importance of multiple information sources to understand dynamics of fisheries. Collaborative investigation of such divergence may facilitate learning and improve fisheries governance.

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*Correspondence: Dr Tim Daw e-mail:
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Adams W.M., Brockington D., Dyson J. & Vira B. (2003) Managing tragedies: understanding conflict over common pool resources. Science 302 (5652): 19151916.
Ames T. (2007) Putting fishers' knowledge to work: reconstructing the Gulf of Maine cos spawning grounds on the basis of local ecological knowledge. In: Fishers' Knowledge in Fisheries Science and Management, ed. Haggan N., Neis B. & Baird I.G., pp. 353363. Paris, France: UNESCO.
Armitage D.R., Plummer R., Berkes F., Arthur R.I., Charles A.T., Davidson-Hunt I.J., Diduck A.P., Doubleday N.C., Johnson D.S., Marschke M., McConney P., Pinkerton E.W. & Wollenberg E.K. (2009) Adaptive co-management for social–ecological complexity. Frontiers in Ecology and the Environment 7 (2): 95102.
Balcetis E. & Dunning D. (2007) Cognitive dissonance and the perception of natural environments. Psychological Science 18 (10): 917921.
Berkes F. (2006) From community-based resource management to complex systems: the scale issue and marine commons. Ecology and Society 11 (1).
Berkes F., Mahon R., McConney P., Pollnac R. & Pomeroy R. (2001) Managing Small-scale Fisheries: Alternative Directions and Methods. Ottawa, Canada: International Development Research Centre.
Bunce M., Rodwell L.D., Gibb R. & Mee L. (2007) Shifting baselines in fishers’ perceptions of island reef fishery degradation. Ocean and Coastal Management. 51 (4): 285302.
Burnham K.P. & Anderson D.R. (2002) Model Selection and Multimodel Inference: a Practical Information-theoretic Approach. New York, NY, USA: Springer-Verlag.
Carpenter S.R. & Brock W.A. (2006) Rising variance: a leading indicator or ecological transition. Ecology Letters 9: 311318.
Charles A.T. (1998) Living with uncertainty in fisheries: analytical methods, management priorities and the Canadian groundfishery experience. Fisheries Research 37: 3750.
Crona B. & Bodin O. (2006) What you know is who you know? Communication patterns among resource users as a prerequisite for co-management. Ecology and Society 11 (2).
Davis A. & Wagner J.R. (2003) Who knows? On the importance of identifying ‘Experts’ when researching local ecological knowledge. Human Ecology 31 (3): 463489.
Daw T.M. (2008) How fishers count: engaging fishers’ knowledge in fisheries science and management. Ph.D. thesis, School of Marine Science and Technology, and School of Geography, Politics and Sociology, Newcastle University, Newcastle upon Tyne, UK [www document]. URL
de Mutsert K., Cowan J.H., Essington T.E. & Hilborn R. (2008) Reanalyses of Gulf of Mexico fisheries data: landings can be misleading in assessments of fisheries and fisheries ecosystems. Proceedings of the National Academy of Sciences 105 (7): 27402744.
Dulvy N.K. & Polunin N.V.C. (2004) Using informal knowledge to infer human-induced rarity of a conspicuous reef fish. Animal Conservation 7: 365374.
Edgar G.J., Barrett N.S. & Morton A.J. (2004) Biases associated with the use of underwater visual census techniques to quantify the density and size-structure of fish populations. Journal of Experimental Marine Biology and Ecology 308 (2): 269290.
Eigaard O.R. (2009) A bottom-up approach to technological development and its management implications in a commercial fishery. ICES Journal of Marine Sciences 66: 916927.
FAO (2005) Putting into practice the ecosystem approach to fisheries. Report. Food and Agriculture Organization of the United Nations, Rome, Italy: 76 pp.
Fazey I., Fazey J.A., Salisbury J.G., Lindenmayer D.B. & Dovers S. (2006) The nature and role of experiential knowledge for environmental conservation. Environmental Conservation 33 (1): 110.
Finlayson A.C. (1994) Fishing for Truth: A Sociological Analysis of Northern Cod Stock Assessments from 1977 to 1990. St Johns, Newfoundland, Canada: ISER.
Folke C., Colding J. & Berkes F. (2003) Chapter 14. Synthesis. In: Navigating Social-Ecological Systems: Building Resilience for Complexity and Change, ed. Berkes F., Colding J. & Folke C., pp. 129. Cambridge, UK: Cambridge University Press.
Froese R. & Pauly D., eds (2006) FishBase [www document]. URL
Gerhardinger L.C., Marenzi R.C., Bertoncini A.A, Medeiros R.P. & Hostim-Silva M. (2006) Local ecological knolwedge on the goliath grouper Epinephelus itajara (Teliostei: Serranidae) in southern Brazil. Neotropical Ichthyology 4 (4): 441450.
Graham N.A.J., Wilson S.K., Jennings S., Polunin N.V.C., Bijoux J.P. & Robinson J. (2006) Dynamic fragility of oceanic coral reef ecosystems. Proceedings of the National Academy of Sciences of the United States of America 103 (22): 84258429.
Graham N.A.J., Wilson S.K., Jennings S., Polunin N.V.C., Bijoux J.P. & Daw T.M. (2007) Lag effects in the impacts of mass coral bleaching on coral reef fish, fisheries and ecosystems. Conservation Biology 21 (5): 12911300.
Gray T., Hatchard J., Daw T.M. & Stead S.M. (2008) New cod war of words: ‘cod is God’ versus ‘sod the cod’: two opposed discourses on the North Sea Cod Recovery Programme. Fisheries Research 93 (1–2): 17.
Haggan N. & Neis B. (2007) The changing face of fisheries science and management. In: Fishers’ Knowledge in Fisheries Science and Management, ed. Haggan N., Neis B. & Baird I.G., pp. 421432. Paris, France: UNESCO.
Haggan N., Neis B. & Baird I.G. (2007) Fishers’ Knowledge in Fisheries Science and Management. Paris, France: UNESCO: 437 pp.
Hall-Arber M. (2003) It's pretty fishy . . . Maritime Studies 2 (1): 4244.
Harmon-Jones E. & Harmon-Jones C. (2007) Cognitive dissonance theory after 50 years of development. Zeitschrift für Sozialpsychologie 38: 716.
Hilborn R. & Walters C.J. (1992) Quantitative Fisheries Stock Assessment. Choice, Dynamics and Uncertainty. New York, NY, USA: Chapman and Hall: 570 pp.
Hoefnagel E., Burnett A. & Wilson D.C. (2006) Chapter 4. The knowledge base of co-management. In: The Knowledge Base for Fisheries Management, ed. Motos L. & Wilson D.C., pp. 85108. Amsterdam, the Netherlands: Elsevier.
Hoffmann-Riem H. & Wynne B. (2002) In risk assessment, one has to admit ignorance: explaining there are things we can't know could improve public confidence in science. Nature 416: 123123.
Holm P. (2003) Crossing the border: on the relationship between science and fishermen's knowledge in a resource management context. Maritime Studies 2: 533.
Hsieh C.H., Reiss C.S. Hunter J.R. Beddington J.R., May R.M. & Sugihara G. (2006) Fishing elevates variability in the abundance of exploited species. Nature 443 (7113): 859862.
Jennings S., Grandcourt E.M. & Polunin N.V.C. (1995) The effects of fishing on the diversity, biomass and trophic structure of Seychelles’ reef fish communities. Coral Reefs 14: 225235.
Jennings S., Kaiser M.J. & Reynolds J.D. (2001) Marine Fisheries Ecology. Malden, UK: Blackwell: 417 pp.
Jentoft S., McCay B.J. & Wilson D.C. (1998) Social theory and fisheries co-management. Marine Policy 22 (4–5): 423436.
Johannes R.E. (1998) The case for data-less marine resource management: examples from tropical nearshore finfisheries. Trends in Ecology and Evolution 13 (6): 243245.
Johannes R.E. & Neis B. (2007) The value of anecdote. In Fishers’ Knowledge in Fisheries Science and Management, ed. Haggan N., Neis B. & Baird I.G., pp. 4158. Paris, France: UNESCO.
Kollmuss A. & Agyeman J. (2002) Mind the gap: why do people act environmentally and what are the barriers to pro-environmental behavior? Environmental Education Research 8 (3): 239260.
Lavides M.N., Polunin N.V.C., Stead S.M., Tabaranza D.G., Comeros M.T. & Dongallo J.R. (2009) Finfish disappearances around Bohol, Philippines inferred from traditional ecological knowledge. Environmental Conservation 36: 235244.
Letourneur Y., Kulbicki M. & Labrosse P. (1998) Length-weight relationships of fishes from coral reefs and lagoons of New Caledonia: an update. Naga ICLARM Quarterly 21: 3946.
Lunn K.E. & Dearden P. (2006) Monitoring small-scale marine fisheries: an example from Thailand's Ko Chang archipelago. Fisheries Research 77: 6070.
Matlin M.W. (2004) Cognition. Hoboken, NY, USA: Wiley.
Maurstad A. (2000) Trapped in biology: an interdisciplinary attempt to integrate fish harvesters’ knowledge into Norwegian fisheries management. In: Finding Our Sea Legs: Linking Fishery People and Their Knowledge with Science and Managment, ed. Neis B. & Felt L., pp. 135152. St Johns, Newfoundland, Canada: ISER.
McClanahan T.R., Hicks C.C. & Darling E.S. (2008) Malthusian overfishing and efforts to overcome it on Kenyan coral reefs. Ecological Applications 18 (6): 15161529.
Mees C.C. (1990) Seychelles artisanal catch assessment survey: notes for implementation. Report. Seychelles Fishing Authority, Victoria, Seychelles: 39 pp.
Miller C.A. (2000) The dynamics of framing environmental values and policy: four models of societal processes. Environmental Values 9: 211233.
Moller H., Berkes F. Lyver P.O.B. & Kislalioglu M. (2004) Combining science and traditional ecological knowledge: monitoring populations for co-management. Ecology and Society 9 (3): 2.
Murray G.., Neis B., Palmer C. & Schneider D. (2008) Mapping cod: fisheries science, fish harvesters' ecological knowledge and cod migrations in the northern Gulf of St Lawrence. Human Ecology 36 (4): 581598.
Neis B. (1997) Fishers' ecologcal knowledge and stock assessment in Newfoundland. In: How deep is the Ocean? Historical Essays on Canada's Atlantic Fishery, ed. Candow J.E. & Corbin C., pp. 243260. Sydney, Nova Scotia, Canada: University College of Cape Breton Press.
Neis B., Schneider D.C., Felt L., Haedrich R.L., Fischer J. & Hutchings J.A. (1999) Fisheries assessment: what can be learned from interviewing resource users? Canadian Journal of Fisheries and Aquatic Sciences 56 (10): 19491963.
O'Donnell K.P., Pajaro M.G. & Vincent A.C.J. (2010) How does the accuracy of fisher knowledge affect seahorse conservation status? Animal Conservation 13: 526533.
Oostenbrugge J.A.E., Densen , W.L.T. & Machiels M.A.M. (2001) Risk aversion in allocating fishing effort in a highly uncertain coastal fishery for pelagic fish, Moluccas, Indonesia. Canadian Journal of Fisheries and Aquatic Sciences 58 (8): 16831691.
Ostrom E., Burger J., Field C.B., Norgaard R.B. & Policansky D. (1999) Revisiting the commons: local lessons, global challenges. Science 284: 278282.
Papworth S.K., Rist J., Coad L. & Milner-Gulland E.J. (2009) Evidence for shifting baseline syndrome in conservation. Conservation Letters 2 (2): 93100.
Pet-Soede C., Van Densen W.L.T., Hiddink J.G., Kuyl S. & Machiels M.A.M. (2001) Can fishermen allocate their fishing effort in space and time on the basis of their catch rates? An example from Spermonde Archipelago, SW Sulawesi, Indonesia. Fisheries Management and Ecology 8 (1): 1536.
Quirijns F.J., Poos J.J. & Rijnsdorp A.D. (2008) Standardizing commercial cpue data in monitoring stock dynamics: accounting for targeting behaviour in mixed fisheries. Fisheries Research 89: 18.
Robinson J., Isidore M.,. Marguerite M.A., Öhman M.C. & Payet R.J. (2004) Spatial and temporal distribution of reef fish spawning aggregations in the Seychelles: an interview-based survey of artisanal fishers. Western Indian Ocean Journal of Marine Science 3: 6369.
Rochet M-J., Prigent M., Bertrand J.A., Carpentier A., Coppin F., Delpech J-P., Fontenelle G., Foucher E., Mahé K., Rostiaux E. & Trenkel V.M. (2008) Ecosystem trends: evidence for agreement between fishers’ perceptions and scientific information. ICES Journal of Marine Science 65: 10571068.
Saenz-Arroyo A., Roberts C.M., Torre J., Carino-Olvera M. & Enriquez-Andrade R.R. (2005) Rapidly shifting environmental baselines among fishers of the Gulf of California. Proceedings of the Royal Society B-Biological Sciences 272 (1575): 19571962.
Schwarz N. (1999) Self-reports: how questions shape the answers. American Psychologist 54 (2): 93105.
Tversky A. & Kahnema D. (1973) Availability: a heuristic for judging frequency and probability. Cognitive Psychology 5: 207232.
Tversky A. & Kahneman D. (1974) Judgment under uncertainty: heuristics and biases. Science 185: 11241131.
van Densen W.L.T. (2001) On the perception of time trends in resource outcome. Its importance in fisheries co-management, agriculture and whaling. Ph.D. thesis. Twente University, Enschede, the Netherlands: 299 pp.
Walmsley S., Howard C. & Medley P. (2005) Participatory Fisheries Stock Assessment (ParFish): Guidelines. London, UK: MRAG: 166 pp.
Verweij M.C., van Densen W.L.T. & Mol A.J.P. (2010) The tower of Babel: different perceptions and controversies on change and status of North Sea fish stocks in multi-stakeholder settings. Marine Policy 34 (3): 522533.
Zuur A.F., Ieno E.N. & Smith G.M. (2007) Analysing Ecological Data. New York, NY, USA: Springer-Verlag: 672 pp.
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