Assessing the effects of moving to maximum economic yield effort level in the western rock lobster fishery of Western Australia Chris Reid 1 , Nick Caputi n , Simon de Lestang, Peter Stephenson Western Australian Fisheries and Marine Research Laboratories, Department of Fisheries, Western Australia, PO Box 20, North Beach, WA 6920, Australia article info Article history: Received 29 November 2011 Received in revised form 27 November 2012 Accepted 27 November 2012 Available online 10 January 2013 Keywords: Western rock lobster Maximum economic yield Input control Catch prediction Decision rule Target reference point abstract The western rock lobster (Panulirus cygnus) fishery has been facing significant economic pressure from increasing costs, lower prices as well as predicted reduced catches due to low recruitment. A maximum economic yield (MEY) assessment estimated the fishing effort that would maximise the net present value of profits over 2008/09–2013/14 was about 50%–70% reduction of 2007/08 effort. The assessment accounted for fixed vessel costs and the variable pot lift cost. An important component of this assessment was the use of puerulus settlement time series that provided a reliable predictor of recruitment to the fishery 3–4 years later. This can be contrasted to most MEY assessments that would use an average catch-effort relationship rather than taking into account the expected recruitment. This predictive ability has been particularly useful as there has been a period of unusually low puerulus settlements over the 5 years (2006/07–2010/11) including the lowest two settlements in the 40-year time series. Due to the low settlements, substantial management changes were implemented in 2008/ 09 and 2009/10 (44% and 73% reduction in nominal fishing effort, respectively compared to 2007/08) to maintain the breeding stock at sustainable levels by having a significant carryover of legal lobsters into future years of lower recruitment. These effort reductions provided a unique opportunity to assess the economic impact of a fishery moving to an MEY effort level over two years. The CPUE increased from 1.1 kg/pot lift in 2007/08 to 1.7 and 2.7 in 2008/09 and 2009/10, respectively. These CPUEs were much higher than the expected levels (1.2 and 1.1, respectively) if the 2007/08 effort had been maintained in these two years. The vessel numbers declined by 14% and 36% in 2008/09 and 2009/10, respectively, compared to 2007/08. The fishery profit increased by AUS$13 and 49 million for 2008/09 and 2009/10, respectively, compared to that estimated if the 2007/08 effort level had continued. This assessment demonstrates the economic benefits of fishing at a level close to that estimated for MEY under an input management regime. The management decision-rule framework is currently based on having the egg production above a threshold reference level to ensure sustainability and now a target reference point based on MEY principles is also being considered. Crown Copyright & 2013 Published by Elsevier Ltd. All rights reserved. 1. Introduction The western rock lobster Panulirus cygnus is exploited by commercial and recreational fishers along the lower west coast of Western Australia (Fig. 1). The commercial fishery is Australia’s largest single-species fishery, worth $200–$400 million annually with catches over the past decade averaging about 11,000 t. Western rock lobster is the basis of the economy of a number of coastal towns and also supports an important recreational fishery. Historically the main focus of the assessment of the fishery has been on the status of the breeding stock to ensure biological sustainability. However the commercial fishery has been facing significant economic pressure from increasing costs and lower prices for lobsters as well as predicted reduced catches as a result of low recruitment. It has therefore been important to consider a bioeconomic assessment of the management strategies to ensure economic optimisation of the fishery as well as ensuring that the breeding stock is maintained. Hence the economic performance of the fishery has been receiving greater scrutiny in recent years [1] and a comparison of the economic effects of the different manage- ment strategies proposed for 2005/06 was undertaken [2]. In 2008, an assessment of the maximum economic yield (MEY) was undertaken to assess the level of fishing effort that would maximise the net present value of profits over a 6 years period. Maximum economic yield (MEY) occurs when the sustainable catch or effort level for the fishery as a whole maximises profits, or creates the largest difference between total revenues and the Contents lists available at SciVerse ScienceDirect journal homepage: www.elsevier.com/locate/marpol Marine Policy 0308-597X/$ - see front matter Crown Copyright & 2013 Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.marpol.2012.11.005 n Corresponding author. Tel.: þ61 8 92030165; fax: þ61 8 92030199. E-mail addresses: reidffa@yahoo.com.au (C. Reid), Nick.Caputi@fish.wa.gov.au (N. Caputi), simon.delestang@fish.wa.gov.au (S. de Lestang), peter.stephenson@fish.wa.gov.au (P. Stephenson). 1 Present address: Forum Fisheries Agency, PO Box 629, Honiara, Solomon Islands. Marine Policy 39 (2013) 303–313