ISSN 1063-0740, Russian Journal of Marine Biology, 2012, Vol. 38, No. 6, pp. 448–453. © Pleiades Publishing, Ltd., 2012. Published in Russian in Biologiya Morya, 2012. 448 1 Marine lobsters include 10 families 33 genera and 149 species and are distributed circumglobally [1, 2]. In Pakistan two lobster families namely Palinuridae and Scyllaridae are reported [6, 22]. Commonly occurring species of family Palinuridae are Panulirus polyphagous, P. homarus and P. versicolor, whereas family Scyllaridae includes Thenus orientalis and Scyl- larides tridecnophaga species [22]. Some aspects of their biology and abundance from Pakistani water were studied [6]. The lobsters are abundantly captured on the Baluchistan coast than the Sindh coast (Table 1 and Fig. 1). During 1971–2007 an average catches of spiny lob- ster (Panulirus spp.) were about 480 t/year [2]. Recently live lobsters and crabs have been exported to China, Malaysia and Singapore. In 2007, total fisher- ies export earning was 188 million USD from frozen fish, shrimps, lobsters, crabs and mollusks [2]. Biomass dynamic models (BDMs) also known as surplus production models (SPMs) are an important approach to the study of harvested populations. On the production modeling various fisheries specialist’s incredible work has been accounted from different parts of the world [3, 4, 8, 10, 14, 15–18, 20, 21, 23] 1 Article is published in the original. Panhwar et al. [13] described the maximum sustain- able yield of ladypees, Silago sihama fishery in Paki- stan. Hilborn and Walters [4] suggested that in tropical fisheries where catch consists of many species and the catch data are difficult to collect by species and when the management regulations are also difficult to make species specific. Treating the entire catch of any fish- ery considered as a biomass dynamic pool is more appropriate than single species dynamics. Generally production models are based on the sim- ple equations, comprising of two or three parameters and population state and fishing activity could be described by a single variable [8]. In a particular case for the analysis of catch and effort data a seven param- eter model was presented [19]. The production of a fish population or other aquatic animals is often sought as a means of establishing an upper limit to the annual harvest [21]. In general fish stocks remain unstable (non-equilibrium state) because of natural mortality, fishing mortality or environmental fluctua- tions, therefore, equilibrium modeling has failed [4]. Up-to-date no published information is available on the stock assessment and management of the spiny lobster fishery in Pakistani waters. This is the first, to estimate times series catch and effort data of spiny lob- ster fishery using catch and effort data analysis FISHERY BIOLOGY Maximum Sustainable Yield Estimates of Spiny Lobster Fishery in Pakistan Using Non-Equilibrium CEDA Package 1 Sher Khan Panhwar a, b , Qun Liu a , Fozia Khan a , and Baradi Waryani c a College of Fisheries, Ocean University of China, China b Center of Excellence in Marine Biology, University of Karachi, Pakistan c Department of Freshwater Biology and Fisheries, University of Sindh, Jamshoro, Pakistan e-mail: skpanhwar@yahoo.com Received March 29, 2012 Abstract—Maximum sustainable yield estimates of spiny lobster fishery were analyzed using catch effort data analysis (CEDA) computer programme. The major parameters of this package are: Maximum sustainable yield (MSY), catchability coefficient (q) carrying capacity (K), intrinsic growth rate (r), Replacement yield and Final population. CEDA has ability to assess the parameters of Fox, Schaefer and Pella-Tomlinson mod- els. In addition it has an ability to estimate three error assumptions i.e. normal, log normal and gamma. In this study, the Maximum sustainable yield outputs of three models of Fox, Schaefer and Pella-Tomlinson are: 828 t, 970 t and 970 t respectively. The outputs of error assumption of normal and log normal are 983 t (R 2 = 0.57) and 950 t (R 2 = 0.53) in Schaefer and Pella-Tomlinson models respectively. MSY outputs of normal error assumption of Fox are 817 t (R 2 = 0.56). All the gamma error assumptions are (790 t) similar. The coef- ficient of variation (cv) of the estimated MSY was about 0.7 and the larger value (1.0) whereas lowest (0.5) were recorded. The Fox model output are more conservative hence the best fits and is close to the annual aver- age landings of the spiny lobster fishery in Pakistan. Keywords: Spiny lobster, maximum sustainable yield, fishery, CEDA, Pakistan DOI: 10.1134/S1063074012060077