Stock-recruitment relationships of the tiger prawns (Penaeus esculentus and Penaeus semisulcatus) in the Australian northern prawn fishery

1996 ◽  
Vol 47 (1) ◽  
pp. 87 ◽  
Author(s):  
YG Wang ◽  
D Die
Keyword(s):  
Population Model ◽  
Fishing Effort ◽  
Maximum Sustainable Yield ◽  
Production Model ◽  
Commercial Catch ◽  
Penaeus Semisulcatus ◽  
Spawning Stock ◽  
Tiger Prawn ◽  
Stock Recruitment ◽  
Northern Prawn Fishery

This paper investigates the stock-recruitment and equilibrium yield dynamics for the two species of tiger prawns (Penaeus esculentus and Penaeus semisulcatus) in Australia's most productive prawn fishery: the Northern Prawn Fishery. Commercial trawl logbooks for 1970-93 and research surveys are used to develop population models for these prawns. A population model that incorporates continuous recruitment is developed. Annual spawning stock and recruitment indices are then estimated from the population model. Spawning stock indices represent the abundance of female prawns that are likely to spawn; recruitment indices represent the abundance of all prawns less than a certain size. The relationships between spawning stock and subsequent recruitment (SRR), between recruitment and subsequent spawning stock (RSR), and between recruitment and commercial catch were estimated through maximum-likelihood models that incorporated autoregressive terms. Yield as a function of fishing effort was estimated by constraining to equilibrium the SRR and RSR. The resulting production model was then used to determine maximum sustainable yield (MSY) and its corresponding fishing effort (fMSY). Long-term yield estimates for the two tiger prawn species range between 3700 and 5300 t. The fishing effort at present is close to the level that should produce MSY for both species of tiger prawns. However, current landings, recruitment and spawning stock are below the equilibrium values predicted by the models. This may be because of uncertainty in the spawning stock-recruitment relationships, a change in carrying capacity, biased estimates of fishing effort, unreliable catch statistics, or simplistic assumptions about stock structure. Although our predictions of tiger prawn yields are uncertain, management will soon have to consider new measures to counteract the effects of future increases in fishing effort.

Reproductive dynamics of the grooved tiger prawn, Penaeus semisulcatus, in the north-western Gulf of Carpentaria, Australia

1987 ◽  
Vol 38 (1) ◽  
pp. 79 ◽  
Author(s):  
PJ Crocos
Keyword(s):  
Egg Production ◽  
Fishing Effort ◽  
Minimum Size ◽  
Limited Area ◽  
The North ◽  
Penaeus Semisulcatus ◽  
Spawning Stock ◽  
Tiger Prawn ◽  
A Minor ◽  
North Western

The reproductive cycle of female P. semisulcatus was investigated in the region north of Groote Eylandt in the Gulf of Carpentaria from August 1983 to March 1985. Approximately 1750 trawls were carried out over 21 monthly sampling cruises, and 13 748 females were examined. The minimum size at maturity was 29 mm carapace length (CL), and 50% of the population were mature at 39 mm CL. The proportion of females which had mated increased sharply above 34 mm CL with a maximum of 80% of females inseminated in the size range 38-54 mm CL. An index of population egg production, calculated from female abundance, the proportion of females spawning and fecundity according to size, was used as an indicator of reproductive output. Egg production was markedly seasonal, with a major spawning peak in August-September, and a minor one in February. Spawning occurred in a limited area within rhe study area. The spawning stock of P. semisulcatus is likely to be vulnerable to fishing pressure because the area and time of major spawning coincides with the major fishing effort in the region.

Integrating size-structured assessment and bioeconomic management advice in Australia's northern prawn fishery

2010 ◽  
Vol 67 (8) ◽  
pp. 1785-1801 ◽  
Author(s):  
André E. Punt ◽  
Roy A. Deng ◽  
Catherine M. Dichmont ◽  
Tom Kompas ◽  
William N. Venables ◽  
...  
Keyword(s):  
Population Model ◽  
Net Present Value ◽  
Fishing Effort ◽  
Bioeconomic Model ◽  
Short Term ◽  
Time Step ◽  
Structured Population Model ◽  
Penaeus Semisulcatus ◽  
Management Advice ◽  
Northern Prawn Fishery

Abstract Punt, A. E., Deng, R. A., Dichmont, C. M., Kompas, T., Venables, W. N., Zhou, S., Pascoe, S., Hutton, T., Kenyon, R., van der Velde, T., and Kienzle, M. 2010. Integrating size-structured assessment and bioeconomic management advice in Australia's northern prawn fishery. – ICES Journal of Marine Science, 67: 1785–1801. Three species in Australia's northern prawn fishery (Penaeus semisulcatus, P. esculentus, and Metapenaeus endeavouri) are assessed using a size-structured population model that operates on a weekly time-step. The parameters of this multispecies population model are estimated using data on catches, catch rates, length frequency data from surveys and the fishery, and tag release–recapture data. The model allows for the technical interaction among the three species. The results from the multispecies stock assessment are used to calculate the time-series of catches and levels of fishing effort that maximize net present value. The bioeconomic model takes into account costs which are proportional to catches and those which are proportional to fishing effort, as well as fixed costs. The sensitivity of the results is examined by changing the assumptions regarding the values for the economic parameters of the bioeconomic model as well as those on which the assessment are based. The results suggest that fishing effort needs to be reduced in the short term to achieve economic goals, although most stocks are estimated currently to be above the stock size corresponding to maximum sustainable yield. Short-term catches and effort levels are sensitive to model assumptions, and in particular, to trends in prices and costs.

scholarly journals Improving catch prediction for tiger prawns in the Australian northern prawn fishery

2014 ◽  
Vol 72 (1) ◽  
pp. 117-129 ◽  
Author(s):  
Roy A. Deng ◽  
André E. Punt ◽  
Catherine M. Dichmont ◽  
Rik C. Buckworth ◽  
Charis Y. Burridge
Keyword(s):  
Population Model ◽  
Frequency Data ◽  
Length Frequency ◽  
Structured Population Model ◽  
Structured Population ◽  
Penaeus Semisulcatus ◽  
Tiger Prawn ◽  
Length Frequency Data ◽  
Northern Prawn Fishery ◽  
Quantities Of Interest

Abstract Population models form the basis for the assessments of species in the tiger prawn component of Australia's northern prawn fishery. Penaeus semisulcatus and P. esculentus are assessed using a size-structured population model. These assessments form the basis for a control rule which predicts future total allowable catches (TACs) for P. semisulcatus and P. esculentus so that the discounted profit from the fishery is maximized. However, there are concerns with this approach: (i) the TAC predictions have consistently overpredicted actual catches and (ii) the assessment for one of the species exhibits a retrospective pattern. A series of analyses was conducted to explore the causes of these observations. Results indicate that catch, effort, and recruitment prediction can be improved substantially by changing the assumed selectivity pattern for one of the surveys, changing how the length frequency data are assembled from the raw data collected, changing the constraints on the minimum amount of effort by target fleet, modifying how the distribution of effort by week is forecasted, and dropping the length frequency data from the most recent recruitment survey. More generally, the analyses illustrate how retrospective analysis can be used to improve how assessments and projections are undertaken when the quantities of interest are known retrospectively.

scholarly journals Sustainable exploitation of temperate fish stocks

2009 ◽  
Vol 6 (1) ◽  
pp. 124-127 ◽  
Author(s):  
Henrik Sparholt ◽  
Robin M. Cook
Keyword(s):  
Species Interactions ◽  
Fishery Management ◽  
Regional Scale ◽  
Single Species ◽  
Fishing Effort ◽  
Theoretical Concept ◽  
Maximum Sustainable Yield ◽  
Production Model ◽  
The Status ◽  
Long Time

The theory of maximum sustainable yield (MSY) underpins many fishery management regimes and is applied principally as a single species concept. Using a simple dynamic biomass production model we show that MSY can be identified from a long time series of multi-stock data at a regional scale in the presence of species interactions and environmental change. It suggests that MSY is robust and calculable in a multispecies environment, offering a realistic reference point for fishery management. Furthermore, the demonstration of the existence of MSY shows that it is more than a purely theoretical concept. There has been an improvement in the status of stocks in the Northeast Atlantic, but our analysis suggests further reductions in fishing effort would improve long-term yields.

scholarly journals The status of Japanese fisheries relative to fisheries around the world

2017 ◽  
Vol 74 (5) ◽  
pp. 1277-1287 ◽  
Author(s):  
Momoko Ichinokawa ◽  
Hiroshi Okamura ◽  
Hiroyuki Kurota
Keyword(s):  
Maximum Sustainable Yield ◽  
Production Model ◽  
Structured Population Model ◽  
Total Allowable Catch ◽  
Quick Recovery ◽  
Stock Status ◽  
Surplus Production Model ◽  
The Status ◽  
Stock Recruitment ◽  
Age Structured

We present the first quantitative review of the stock status relative to the stock biomass (B) and the exploitation rate (U) that achieved the maximum sustainable yield (MSY) (BMSY and UMSY, respectively) for 37 Japanese stocks contributing 61% of the total marine capture production in Japan. BMSY and UMSY were estimated by assuming three types of stock-recruitment (S-R) relationships and an age-structured population model or by applying a surplus production model. The estimated stock status shows that approximately half of the stocks were overfishing (U/UMSY > 1), and approximately half of the stocks were overfished (B/BMSY < 0.5) during 2011–2013. Over the past 15 years, U decreased and B slightly increased on average. The rate of decrease in the U of the stocks managed by the total allowable catch (TAC) was significantly greater than that of the other stocks, providing evidence of the effectiveness of TAC management in Japan. The above statuses and trends were insensitive to the assumption of the S-R relationship. The characteristics of Japanese stocks composed mainly of resources with relatively high natural mortality, i.e. productivity, suggest that Japanese fisheries have great potential of exhibiting a quick recovery and increasing their yield by adjusting the fishing intensity to an appropriate level.

scholarly journals Sustainable Potential of Tuna Fishery Around the Waters of North Sulawesi Province Based on Data from the Bitung Ocean Fisheries Port (PPS)

2019 ◽  
Vol 10 (1) ◽  
pp. 18
Author(s):  
Donald H. Simanjuntak ◽  
Lawrence J. L. Lumingas ◽  
Joudy R. R. Sangari
Keyword(s):  
Secondary Data ◽  
Fishing Effort ◽  
Maximum Sustainable Yield ◽  
Production Model ◽  
Utilization Rate ◽  
Sustainable Yield ◽  
North Sulawesi ◽  
Surplus Production Model ◽  
Tuna Fishing ◽  
Tuna Fisheries

This research was conducted in the city of Bitung, North Sulawesi Province with activities centered on the Bitung Ocean Fisheries Port (PPS), which began from mid March to April 2019. The fishing activities studied are using the fishing areas around the waters of  North Sulawesi Province namely the Sulawesi Sea and The Maluku Sea which are included in WPP 715 and 716 based on tuna catch landed data on PPS Bitung. The purpose of this study was to analyze the value of sustainable potential by looking at the level of utilization and Maximum Sustainable Yield (MSY) of tuna in the waters around North Sulawesi Province based on a surplus production model approach (Schaefer Model). This research is expected to be used as a consideration in the management of tuna stocks around the waters of North Sulawesi Province, and can be used as a basis for further research. This study uses a secondary data collection method in the form of fishery statistics documents. The data used are data from tuna fishing and fishing (effort), from 2014 to 2018 (5 years). The results showed that the sustainable potential of tuna fisheries around the waters of North Sulawesi Province based on North Sulawesi PPS data indicated that, the sustainable potential value of tuna that could be caught was 14,173.51 tons / year which is counted as 80% of the value of tuna resources around the waters of North Sulawesi Province. PPS Bitung data which amounted to 17,716.15 tons / year for Hmsy, 1,200.15 trips / year for Emsy, with an average CPUE value of 2014-2018 of 19 tons / trip. The level of tuna utilization around the waters of North Sulawesi Province is based on data from PPS Bitung in 2014, 2017 and 2018 which indicate that there were indications of overfishing with the largest utilization rate in 2014 which reached a value of 155.09%.Keywords: tuna, Bitung, Bitung PPS, sustainable potential, MSY. ABSTRAKKegiatan penelitian ini berlangsung di Kota Bitung, Provinsi Sulawesi Utara dengan kegiatan berpusat di Pelabuhan Perikanan Samudera (PPS) Bitung, yang dimulai  dari pertengahan bulan Maret hingga bulan April 2019. Aktivitas perikanan tangkap yang ditelaah berlangsung di sekitar perairan Provinsi Sulawesi Utara yaitu Laut Sulawesi dan Laut Maluku yang masuk ke dalam WPP 715 dan 716 berdasarkan data tangkapan tuna yang didaratkan di PPS Bitung. Tujuan dari penelitian ini adalah untuk menganalisis nilai potensi lestari dengan melihat tingkat pemanfaatan dan maximum sustainable yield (MSY) ikan tuna di sekitar perairan Provinsi Sulawesi Utara berdasarkan pendekatan model produksi surplus (Model Schaefer). Penelitan ini diharapkan dapat digunakan sebagai bahan pertimbangan dalam pengelolaan stok ikan tuna di sekitar perairan Provinsi Sulawesi Utara, serta dapat digunakan sebagai dasar untuk penelitian selanjutnya.  Penelitian ini menggunakan metode pengumpulan data sekunder berbentuk dokumen. Data yang diambil adalah data tangkapan ikan tuna dan upaya penangkapan ikan atau effort (trip), dari tahun 2014 sampai dengan 2018 (5 Tahun). Hasil penelitian menunjukkan potensi lestari perikanan tuna di sekitar perairan Provinsi Sulawesi Utara berdasarkan data PPS Bitung Sulawesi Utara nilai potensi lestari tuna yang bisa ditangkap adalah 14.173,51 ton/tahun 80% dari nilai pemanfaatan sumber daya perikanan tangkap tuna di sekitar perairan Provinsi Sulawesi Utara berdasarkan data PPS Bitung yang sebesar 17.716,15 ton/tahun untuk Hmsy, 1.200,15 trip/tahun untuk Emsy, dengan nilai CPUE rata-rata tahun 2014-2018 sebesar 19 ton/trip. Tingkat pemanfaatan tuna di sekitar perairan Provinsi Sulawesi Utara berdasarkan data PPS Bitung Sulawesi Utara di tahun 2014,2017 dan 2018 sudah yang menandakan adanya indikasi overfishing dengan tingkat pemanfaatan terbesar di tahun 2014 yang mencapai nilai 155,09%.Kata Kunci: ikan tuna, Bitung, PPS Bitung, potensi lestari, MSY.

Population Dynamics of the Arcto-Norwegian Cod

1967 ◽  
Vol 24 (1) ◽  
pp. 145-190 ◽  
Author(s):  
D. J. Garrod
Keyword(s):  
Gadus Morhua ◽  
Barents Sea ◽  
Fishing Effort ◽  
Catch Per Unit Effort ◽  
Group Iii ◽  
Spawning Stock ◽  
Stock Recruitment ◽  
Post War ◽  
The One ◽  
Definition Of

By reason of its geographical distribution, the Arcto-Norwegian cod (Gadus morhua) supports three distinct fisheries, two feeding fisheries in the Barents Sea and at Bear Island–Spitsbergen, and a spawning fishery off the Norway coast. In the past this diversity of fishing on the one stock has made it difficult to unify all the data to give an overall description of post-war changes in the stock. In this contribution three modifications of conventional procedures are introduced which enable this to be done. These are: (i) a system of weighting the catch per unit effort data from each fishery to a level of comparability; (ii) a more rigorous definition of the effective fishing effort on each age-group; (iii) a method of estimation of the effective fishing effort on partially recruited age-groups.Using these methods the analysis presents the effects of fishing on each fishery in the context of its effect on the total stock, and at the same time it indicates ways in which factors other than fishing may have influenced the apparent abundance of the stock. The treatment of the data is also used to derive estimates of spawning stock and recruitment of 3-year-old cod for subsequent analysis of stock–recruitment relationships.

scholarly journals An explicit solution for calculating optimum spawning stock size from Ricker’s stock recruitment model

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1623 ◽  
Author(s):  
Mark D. Scheuerell
Keyword(s):  
Explicit Solution ◽  
Model Fitting ◽  
Maximum Sustainable Yield ◽  
Reference Points ◽  
Stock Size ◽  
Points Of Interest ◽  
Spawning Stock ◽  
Stock Recruitment ◽  
Explicit Formulae ◽  
Recruitment Model

Stock-recruitment models have been used for decades in fisheries management as a means of formalizing the expected number of offspring that recruit to a fishery based on the number of parents. In particular, Ricker’s stock recruitment model is widely used due to its flexibility and ease with which the parameters can be estimated. After model fitting, the spawning stock size that produces the maximum sustainable yield (SMSY) to a fishery, and the harvest corresponding to it (UMSY), are two of the most common biological reference points of interest to fisheries managers. However, to date there has been no explicit solution for either reference point because of the transcendental nature of the equation needed to solve for them. Therefore, numerical or statistical approximations have been used for more than 30 years. Here I provide explicit formulae for calculating bothSMSYandUMSYin terms of the productivity and density-dependent parameters of Ricker’s model.

scholarly journals Delay in fishery management: diminished yield, longer rebuilding, and increased probability of stock collapse1

2006 ◽  
Vol 64 (1) ◽  
pp. 149-159 ◽  
Author(s):  
Kyle W. Shertzer ◽  
Michael H. Prager
Keyword(s):  
Fishery Management ◽  
Economic Loss ◽  
Maximum Sustainable Yield ◽  
Sustainable Yield ◽  
Short Term ◽  
Stock Status ◽  
Stock Biomass ◽  
Spawning Stock ◽  
Stock Recruitment ◽  
Stock Collapse

Abstract Shertzer, K. W., and Prager, M. H. 2007. Delay in fishery management: diminished yield, longer rebuilding, and increased probability of stock collapse. ICES Journal of Marine Science, 64: 149–159. When a stock is depleted, catch reductions are in order, but typically they are implemented only after considerable delay. Delay occurs because fishery management is political, and stricter management, which involves short-term economic loss, is unpopular. Informed of stock decline, managers often hesitate, perhaps pondering the uncertainty of scientific advice, perhaps hoping that a good year class will render action moot. However, management delay itself can have significant costs, when it exacerbates stock decline. To examine the biological consequences of delay, we simulated a spectrum of fisheries under various degrees of delay in management. Increased delay required larger catch reductions, for more years, to recover benchmark stock status (here, spawning-stock biomass at maximum sustainable yield). Management delay caused stock collapse most often under two conditions: (1) when the stock–recruitment relationship was depensatory, or (2) when catchability, unknown to the assessment, was density-dependent and fishing took juveniles. In contrast, prompt management resulted in quicker recoveries and higher cumulative yields from simulated fisheries. Benefits to stock biomass and fishery yield can be high from implementing management promptly.

Stock dynamics and predator–prey effects of Atlantic bonito and bluefish as top predators in the Black Sea

2020 ◽  
Author(s):  
Georgi M Daskalov ◽  
Nazli Demirel ◽  
Aylin Ulman ◽  
Yoana Georgieva ◽  
Mustafa Zengin
Keyword(s):  
Black Sea ◽  
Prey Species ◽  
Maximum Sustainable Yield ◽  
Ecological Impacts ◽  
Reference Points ◽  
Production Model ◽  
Horse Mackerel ◽  
The Black Sea ◽  
Commercial Catch ◽  
General Decline

Abstract This study uses surplus production model-based methods to assess data-poor stocks and estimate key reference points for Atlantic bonito (Sarda sarda) and bluefish (Pomatomus saltatrix) in the Black Sea. Our results demonstrate that the catch maximum sustainable yield (CMSY) method, using catch data only, yields similar results to the more accurate Bayesian Schaefer model (BSM) method, fitted with commercial catch-per-unit-of-effort data, and therefore is suitable in assessing data-poor stocks. We explore the ecological impacts of the two stocks on other commercial species and compare impacts of predation and fishing. Prior to 1995, the consumption of bonito and bluefish on anchovy, horse mackerel, and sprat exceeded the removal of those prey species by the fisheries. Later on, the trends reversed, with catches of prey species becoming more than three times higher than their predation by bonito and bluefish. Horse mackerel, the main prey of bluefish, has declined to critical levels since 1995, which is likely contributing to the general decline in bluefish, along with overfishing. Heavy fishing of bonito and bluefish has caused their current depleted states and combined with their significant impact on prey fish contributed to the ecosystem regime shift in the Black Sea. Due to the present steady positioning of low stock regimes, the recovery of the two stocks need decisive and possibly prolonged rebuilding measures, including a reduction in fishing pressure, efficient control of under-sized catch, and ensuring sufficient prey biomass availability.

Sign in / Sign up

Export Citation Format

Share Document