Overfishing, uncertainty and ocean governance:

The importance of the precautionary approach, the ecosystem approach, and adaptive management in explaining fisheries management failures.

A PhD thesis  2009  Jon Nevill
Published as a book in 2010
School of Government, University of Tasmania, 
Hobart Australia


This thesis explores the idea that poor fisheries management - and the economic and ecological damage which follows - is largely the result of management failures to implement important strategies to account for uncertainty. The two most important of these strategies are the precautionary principle and the ecosystem approach. After investigating the implementation of these strategies in Australian fisheries case studies, the author concludes that implementation is at best incompetent, and at worst dishonest. However, the case study of the southern ocean krill fishery, managed by the Commission for the Conservation of Antarctic Marine Living Resources, provides an important exception. Other case studies include the Western Rock Lobster fishery, the Northern Prawn fishery, the Orange Roughy fishery, and South Australia's abalone fishery.

The study finds strong rhetoric amongst Australian fisheries agencies supporting application of the precautionary and ecosystem approaches. However, in the case studies examined, there is little evidence for enthusiasm (on the part of managers) for actually applying the approaches in a thoughtful or comprehensive way. Examples are discussed showing that agencies have published false and misleading information apparently to create an impression that these  approaches are being effectively implemented. The author speculates as to the reasons behind this behaviour, suggesting that the explanation lies in cultures within fisheries agencies which condone incompetence and foster dishonest reporting.

The central conclusion of the book is that steps must be taken to bring about radical change in the cultures which operate within fisheries agencies. This could be achieved, the author argues, by replacing fisheries management agencies with agencies charged with managing marine biodiversity assets.


“Why does overfishing persist in the face of regulation?” This question, the subject of intense interest and discussion, has no easy or palatable answer. While trawling over old ground, this thesis hopefully offers new insights, and adds weight to important arguments advanced by other writers. I argue here that overfishing, a fundamental cause of the crisis facing our oceans, is the result of the failure of our fisheries management agencies (ultimately our politicians and communities) to embrace a small suite of powerful tools (more correctly strategic approaches) which have been developed to account for uncertainty.

Broad success in managing fisheries to achieve sustainability goals will (I argue) only come if these tools are enthusiastically applied. Moreover, I suggest that this will not happen until organisational cultures within fishery management agencies undergo a major shift.  In my view, the only way this shift will occur is for asset-based biodiversity conservation, rather than resource exploitation, to be placed at the centre of ocean governance.

This thesis examines these issues in the context of case studies covering regional, national and provincial (State) fishery management agencies. With the exception of the case study of a regional fishery (the southern ocean krill fishery) all case studies are drawn from Australian experiences. Commercial and recreational fisheries are considered.

The central recommendation of the thesis is that fishery management agencies, worldwide, should be replaced by biodiversity asset management agencies. While recognising that many factors affect biodiversity assets (some well outside the control of current fishery agencies) such a strategy would mesh with the increasing acceptance of integrated coastal zone management, and in general the need for integrated and precautionary management of natural resources.


ocean governance, ethics, overfishing, uncertainty, precautionary principle, precautionary approach, ecosystem approach, ecosystem based fisheries management, adaptive management, krill, orange roughy, northern prawns, western rock lobster, abalone, spearfishing.

The thesis was examined by two former-CSIRO fisheries scientists. One examiner remarked: "This is an important and courageous work, and should be widely read by fisheries scientists and managers. I encourage you to investigate publishing it as a book".

The thesis was subsequently published as a book under the title "Overfishing under regulation"; see http://www.onlyoneplanet.com/marineFlyerVDM.pdf. The main problem with the book is that it reduced the original A4 format to A5, making the font very small, almost unreadable.

The book can be downloaded from:


Contents page:

Summary paper based on chapter 18
Implementation failures in Australian marine policy.
This paper summaries several of the key issues raised by the thesis.

Entire thesis: as a PDF, or as a DOC file.

Please contact me by email if you would like a copy of my Endnote reference file.