scholarly journals STOCK ASSESSMENT AND LONG-TERM DYNAMICS OF AZOV SEA ROACH (RUSSIAN WATERS), BASED ON CMSY MODEL FOR DATA-LIMITED MODELLING IN PERIOD (1999-2019)

Fisheries ◽  
2020 ◽  
Vol 2020 (6) ◽  
pp. 88-94
Author(s):  
Nikolay Zherdev ◽  
M. Pyatinsky ◽  
Inna Kozobrod
Keyword(s):  
River Flow ◽  
Stock Assessment ◽  
Rutilus Rutilus ◽  
Roach Rutilus Rutilus ◽  
Surplus Production ◽  
Azov Sea ◽  
Production Models ◽  
Stock Biomass ◽  
Russian Waters

Stock assessment of Azov sea roach Rutilus rutilus (Linnaeus, 1758) has been performed by CMSY model in period 1999-2019 by data-limited modelling in R. The current population status – in biological safe zone for stock biomass and no overfishing signals (B2019/BMSY = 1,32, F2019/FMSY = 0,53). Perhaps, current paper results can be a slightly incomplete in background that there is no relevant data about IUU fishery ever exists, which can lead to fishing mortality underestimation. Azov sea roach population continue to be in “depleted” status after river flow regulation in 1950’s. Joined continuous biomass estimates time series over whole fishing his-tory 1932–2019 showed at least 2 population collapses: in 1940’s and 1980’s years. According to model re-sults TAC (total allowed catch) should be accepted at level 516.9 t. If the recommendation is followed stock biomass will stay at safety in level 1828.1 t. Data limited modelling shows a good performance for sea roach in background of data lucking and in this reason still the best choose against cohor or surplus production models.

ACCUMULATION OF HEAVY METALS (CU, ZN, NI, CR, PB, CD) IN TISSUES OF PERCH (PERCA FLUVIATILIS L.) AND ROACH RUTILUS RUTILUS (L.) UNDER EXPERIMENTAL CONDITIONS/SUNKIŲJŲ METALŲ (CU, ZN, NI, CR, PB, CD) KAUPIMASIS EŠERIO PERCA FLUVIATILIS L. IR KUOJOS RUTILUS АККУМУЛЯЦИЯ ТЯЖЕЛЫХ МЕТАЛЛОВ (CU, ZN, NI, CR, PB, CD) В ТКАНЯХ ОКУНЯ PERCA FLUVIATILIS L. И ПЛОТВЫ RUTILLUS RUTILLUS L. В ЭКСПЕРИМЕНТАЛЬНЫХ УСЛОВИЯХ

2008 ◽  
Vol 16 (4) ◽  
pp. 205-212 ◽  
Author(s):  
Raimondas Leopoldas Idzelis ◽  
Vytautas Kesminas ◽  
Gintaras Svecevičius ◽  
Vaidas Misius
Keyword(s):  
Heavy Metals ◽  
Good Condition ◽  
Perca Fluviatilis ◽  
Rutilus Rutilus ◽  
Ecological Monitoring ◽  
Point Of View ◽  
Experimental Conditions ◽  
Roach Rutilus Rutilus ◽  
Perch Perca Fluviatilis

The paper analyses the effects of heavy metals on freshwater fishes. From the point of view of pollution caused by heavy metals, the condition of ecosystems in Lithuania is yet less affected by heavy metals compared to that the world over. Fishes accumulate heavy metals selectively. Fishes mostly accumulate Pb, Cr, Cd. Our experiments showed that MPC (Maximum Permitted Concentration) (0.2 mg/kg) of lead was exceeded 1.6 time in the muscles of perch, and 1.4 time ‐ in the muscles of roach. The MPC (0.05 mg/kg) of cadmium was exceeded 1.2 time in the muscles of perch and roach. It was determined that perch accumulate heavy metals more intensively than roach. Heavy metals accumulate in fishes: liver > muscle> gills. As heavy metals are considered to be one of the most harmful water pollutants, there is a great need for a constant ecological monitoring and reduction of their amounts released into the environment. According to long‐term research data, the MPC in fishes is exceeded only slightly. This confirms a good condition of aquatic ecosystems in Lithuania. Santrauka Įvertintas sunkiųjų metalų pasiskirstymas gėlavandenių žuvų audiniuose monitoringiniuose vandens telkiniuose, taip pat ir kuojų bei ešerių, paveiktų sunkiųjų metalų didžiausiomis leidžiamosiomis koncentracijomis (DLK), audiniuose. Eksperimentiniai tyrimai atlikti su Cu, Zn, Ni, Cr, Pb, Cd, kurių kiekvienas pasižymi kancerogeniniu mutageniniu poveikiu. Nustatyta, kad švino DLK (0,2 mg/kg) buvo viršyta ešerių raumenyse 1,6 karto, o kuojų – 1,4 karto. Kadmio DLK (0,05 mg/kg) ešerių ir kuojų raumenyse buvo viršyta apie 1,2 karto. Taip pat nustatyta, kad ešeriai sunkiuosius metalus kaupia intensyviau nei kuojos. Eksperimentiniai duomenys sutampa su sunkiųjų metalų tyrimų monitoringiniuose vandens telkiniuose duomenimis. Žuvų audiniuose Pb ir Cd koncentracijos yra didžiausios ir dažnai viršija Lietuvos higienos normoje nurodytąją DLK. Tokie rezultatai įpareigoja nuolat kontroliuoti sunkiųjų metalų kiekį žuvyse. Rezultatai pateikiami sunkiųjų metalų sklaidos pasiskirstymo grafikuose. Резюме Представлены данные по распределению тяжелых металлов в тканях пресноводных рыб в мониторинговых водоемах, а также результаты, полученные путем воздействия тяжелых металлов в предельно допустимых концентрациях (ПДК) на окуня и плотву. В экспериментальных исследованиях применялись металлы Cu, Zn, Ni, Cr, Pb, Cd, оказывающие на живые организмы воздействие мутагенного и канцерогенного характера. Установлено, что концентрация Cd в тканях окуня превышала ПДК (0,2 мг/кг) в 1,6 раза, а в тканях плотвы – в 1,4 раза. Концентрация Cd в тканях тех же рыб превышала ПДК (0,05 мг/кг) примерно в 1,2 раза. Также установлено, что окунь аккумулирует тяжелые металлы интенсивнее плотвы. Экспериментальные данные совпадают с данными, полученными в мониторинговых водоемах. Установлено также, что концентрация Pb и Cd в тканях рыб зачастую превышает ПДК. Полученные результаты обязывают постоянно контролировать уровень тяжелых металлов в тканях рыб.

scholarly journals Review of integrated size-structured models for stock assessment of hard-to-age crustacean and mollusc species

2013 ◽  
Vol 70 (1) ◽  
pp. 16-33 ◽  
Author(s):  
Andre E. Punt ◽  
TzuChuan Huang ◽  
Mark N. Maunder
Keyword(s):  
Stock Assessment ◽  
Age Distribution ◽  
Size Composition ◽  
Data Sources ◽  
Multiple Sources ◽  
Surplus Production ◽  
Production Models ◽  
Stock Assessments ◽  
Mollusc Species ◽  
Size At Age

Abstract Punt, A. E., Huang, T., and Maunder, M. N. 2013. Review of integrated size-structured models for stock assessment of hard-to-age crustacean and mollusc species. – ICES Journal of Marine Science, 70:16–33. Crustaceans and molluscs such as crabs, rock lobsters, prawns, abalone, and oysters constitute large and valuable fisheries. However, assessments of these species are hampered because they cannot be production aged, in contrast to many teleosts. The major data sources for these species, in addition to catch and abundance index data, are the size compositions of the catches and of any fishery-independent indices. Assessments of such species have been conducted using age-based methods of stock assessment, as well as surplus production models. However, size-structured methods are now preferred because they can make full use of size-composition data, are able to integrate multiple sources of data, and produce the types of outputs which are needed for management purposes. An advantage of size-based models over age-based models is that all processes can be size-based, and these processes can modify the (unmodelled) size-at-age distribution. We review these methods, highlighting the choices that need to be made when developing integrated size-structured stock assessments, the data sources which are typically available and how they are used for parameter estimation, and contrast a number of such assessments worldwide.

scholarly journals PRELIMINARY STOCK ASSESSMENT RESULTS FOR SHAD IN AZOV-BLACK SEA BASIN IN TERMS OF DATA LUCKING (2007–2020)

2021 ◽  
Vol 1 (6) ◽  
pp. 34-39
Author(s):  
I.D. Kozobrod ◽  
◽  
M.M. Piatinski
Keyword(s):  
Black Sea ◽  
Stock Assessment ◽  
Safe Zone ◽  
Fishing Mortality ◽  
Stock Status ◽  
Azov Sea ◽  
Stock Biomass ◽  
Stock Recovery ◽  
Assessment Results

Black-azov sea shad Alosa immaculate (Bennett, 1835) stock assessment performed by trending model CMSY in terms of data lucking for period 2007–2020 in R. Model results showed current stock status in biological safe zone (B2020 = 2291 t, BMSY = 1855 t, B2020/BMSY = 1,23) with signs of minor overexploitation by fishing mortality (F2020 = 0,35, FMSY = 0,28, F2020/FMSY = 1,25). Obtained stock biomass estimates shows minor Black-Azov sea shad stock recovery evidence in period 2007–2020. Evidence of light population fishery overexploitation after 2018 are found, perhaps, was caused by IUU-fishery. Paper results underline to eliminate and regulate shad illegal, unreported, unregistered fishery in Azov-Black sea basin

scholarly journals Bayesian state-space models with multiple CPUE data: the case of a mullet fishery

2017 ◽  
Vol 81 (3) ◽  
pp. 361 ◽  
Author(s):  
Rodrigo Sant’Ana ◽  
Paul Gerhard Kinas ◽  
Laura Villwock de Miranda ◽  
Paulo Ricardo Schwingel ◽  
Jorge Pablo Castello ◽  
...  
Keyword(s):  
State Space ◽  
Stock Assessment ◽  
Reference Points ◽  
State Space Models ◽  
Southern Population ◽  
Catch Per Unit Effort ◽  
Bayesian Hierarchical ◽  
Surplus Production ◽  
Production Models ◽  
Borrowing Strength

We propose a novel Bayesian hierarchical structure of state-space surplus production models that accommodate multiple catch per unit effort (CPUE) data of various fisheries exploiting the same stock. The advantage of this approach in data-limited stock assessment is the possibility of borrowing strength among different data sources to estimate reference points useful for management decisions. The model is applied to thirteen years of data from seven fisheries of the lebranche mullet (Mugil liza) southern population, distributed along the southern and southeastern shelf regions of Brazil. The results indicate that this modelling strategy is useful and has room for extensions. There are reasons for concern about the sustainability of the mullet stock, although the wide posterior credibility intervals for key reference points preclude conclusive statistical evidence at this time

scholarly journals Characteristics of biology and fishery of roach (Rutilus rutilus L.) in water bodies of the Republic of Karelia

2020 ◽  
Vol 0 (1) ◽  
pp. 7-16
Author(s):  
Nadezhda Stepanovna Cherepanova ◽  
Andrey Georgiev ◽  
Vyacheslav Anatolievich Shirokov
Keyword(s):  
Rutilus Rutilus ◽  
Wide Distribution ◽  
Water Bodies ◽  
Lake Ladoga ◽  
Roach Rutilus Rutilus ◽  
Lake Onega ◽  
The Status ◽  
The Republic ◽  
Mature Part

The article summarizes the results of long-term observations of the status of roach stocks in the main fishing waters of the Republic of Karelia (Lake Onega, Lake Ladoga, Vodlozerо and Topo-Pyaozerо reservoirs, Lake Syamozero). New data on its biology (distribution, linear and weight indicators, abundance, biomass) have been presented. There has been shown the dynamics of roach catch for a long-term period (1950–2017). It has been found that the fishing capacity of the represented roach populations corresponds to the production capabilities of its mature part and to the value obtained by biomass growth. The results of observations showed that in the studied water bodies the number and stocks of roach allow for greater volumes of catch than it is currently available and the total catch can be increased up to the calculated values of the allowable catch subject to rational fishing in the water bodies. Roach should be commercially caught at the age of 4+ years old. Given the interspecific contradictions of roach and bream, intensive fishing is recommended during the period of spawning in the straits, bays and mouths of rivers. For catching roach, it is necessary to use coastal-type fishing gear (trap nets, seines). The intensity of fishing and the increase in catches in reservoirs should be considered as mandatory measures in terms of biological reclamation in water bodies. When allocating catch quotas, the priority should be given to the most productive roach suppliers. The accompanying factor for the wide distribution of roach, along with other spring-spawning carp species (blue bream, bream), in our opinion, is warming of the climate in the region. In this regard, it is necessary to take measures to force catching the above fish species.

DATA LIMITED STOCK ASSESSMENT OF POPULATION DYNAMICS BY CMSY MODEL ON THE EXAMPLE OF BLACK SEA SPRAT IN THE RUSSIAN WATERS

Fisheries ◽  
2021 ◽  
Vol 2021 (3) ◽  
pp. 76-82
Author(s):  
M. Pyatinsky
Keyword(s):  
Black Sea ◽  
Reference Point ◽  
Stock Assessment ◽  
Model Fitting ◽  
Assessment Procedure ◽  
Cohort Model ◽  
Limited Information ◽  
Short Term ◽  
Stock Biomass ◽  
Russian Waters

This study performs approbation of trend CMSY model on the example of Black sea sprat fishing unit, localized in Russian waters. Data sources has been reduced to the level of data limited modeling for indicator and trend models approach. CMSY population model results were compared with previously performed estimations by more powerful cohort model - XSA. CMSY results shows no significant deviations from the XSA results. Forecast scenarios and conclusions based on CMSY model fitting leads to the same statements with previously published results by XSA. CMSY model shows next results: stock biomass in 2019 B2019 = 63,9 ths. t, fishing mortality – F2019 = 0,29. Stock biomass in 2019 was significant below the target reference point BMSY = 105 ths. t and higher then limit reference point Blim = 52,7 ths. t. Some uncertain overexploitation in 2019 was underlined, F2019/FMSY = 1,12. Investigation of forecast scenarios with different total allowed catch levels indicates that there are no features for increasing the catch capacity in short-term projection. CMSY model fitting have passed the necessary stability tests and confirm previously founded results. In summary of this study, we can recommend to use CMSY model for stock assessment procedure in terms of data-limited information background.

Comparative performance of data-poor CMSY and data-moderate SPiCT stock assessment methods when applied to data-rich, real-world stocks

2020 ◽  
Author(s):  
Paul Bouch ◽  
Cóilín Minto ◽  
Dave G Reid
Keyword(s):  
Stock Assessment ◽  
Assessment Methods ◽  
Production Model ◽  
Fishing Mortality ◽  
Comparative Performance ◽  
Fish Stocks ◽  
Surplus Production ◽  
Stock Biomass ◽  
Surplus Production Model ◽  
The Status

Abstract All fish stocks should be managed sustainably, yet for the majority of stocks, data are often limited and different stock assessment methods are required. Two popular and widely used methods are Catch-MSY (CMSY) and Surplus Production Model in Continuous Time (SPiCT). We apply these methods to 17 data-rich stocks and compare the status estimates to the accepted International Council for the Exploration of the Sea (ICES) age-based assessments. Comparison statistics and receiver operator analysis showed that both methods often differed considerably from the ICES assessment, with CMSY showing a tendency to overestimate relative fishing mortality and underestimate relative stock biomass, whilst SPiCT showed the opposite. CMSY assessments were poor when the default depletion prior ranges differed from the ICES assessments, particularly towards the end of the time series, where some stocks showed signs of recovery. SPiCT assessments showed better correlation with the ICES assessment but often failed to correctly estimate the scale of either F/FMSY of B/BMSY, with the indices lacking the contrast to be informative about catchability and either the intrinsic growth rate or carrying capacity. Results highlight the importance of understanding model tendencies relative to data-rich approaches and warrant caution when adopting these models.

scholarly journals Population dynamics and stock assessment of grey sharpnose shark Rhizoprionodon oligolinx Springer, 1964 (Chondrichthyes: Carcharhinidae) from the north-west coast of India

2017 ◽  
Vol 64 (3) ◽  
Author(s):  
G. B. Purushottama ◽  
Gyanaranjan Dash ◽  
Thakur Das ◽  
K. V. Akhilesh ◽  
Shoba Joe Kizhakudan ◽  
...  
Keyword(s):  
Population Dynamics ◽  
Stock Assessment ◽  
Total Mortality ◽  
North West ◽  
The North ◽  
Stock Biomass ◽  
Spawning Stock ◽  
Yield Per Recruit ◽  
Peak Phase

The life history and exploitation parameters of Rhizoprionodon oligolinx Springer, 1964 were assessed using commercial landing data of 2012-2015 from Mumbai waters of India to understand the population dynamics and stock status of the species. The average annual landing of the species was estimated to be 383 t, which formed about 9.1% of the total shark landings of Maharashtra. L∞, K and t0 estimated were 97.1 cm, 0.47 yr-1 and -0.79 yr respectively. Total mortality (Z), fishing mortality (F) and natural mortality (M) rates were estimated as 2.16 yr-1, 1.48 yr-1 and 0.69 yr-1 respectively. The length at capture (L50), length at female maturity (Lm50) and male maturity (Lm50) were estimated as 49.7, 62.3 and 59.5 cm respectively, which indicated that most of the sharks entered peak phase of exploitation before attaining sexual maturity. Length-weight relationship indicated allometric growth (b>3) for the species. The species was found to be a continuous breeder and showed peak recruitment during April. The current exploitation rate (Ecur) was found to be 0.68, which is lower than Emax estimated for the species using Beverton and Holt yield per recruit analysis. Thompson and Bell prediction model showed that at current exploitation level, the biomass (B) has reduced to 32% of virgin biomass (B0) where as, the spawning stock biomass (SSB) has reduced to 16% of the virgin spawning stock biomass (SSB0). Hence the exploitation level for the species should be reduced by 40% that will ensure the availability of SSB at a relatively safer 30% level to rebuild the stock for long term sustainability of the resource.

scholarly journals Comparative characterization of the roach Rutilus rutilus heckelii (Nordmann, 1840) sampled in different areas of the Sea of Azov during its spawning season in 2021, based on its physiological and biochemical parameters

2021 ◽  
Vol 937 (2) ◽  
pp. 022062
Author(s):  
A Vojkina ◽  
L Bugayov ◽  
V Belousov ◽  
V Licovskaya ◽  
O Kirishenko
Keyword(s):  
Biochemical Parameters ◽  
Biochemical Analysis ◽  
Rutilus Rutilus ◽  
Spring Season ◽  
Roach Rutilus Rutilus ◽  
Azov Sea ◽  
Fish Blood ◽  
Physiological And Biochemical ◽  
Low Activity

Abstract Four samples of Rutilus rutilus collected in various water bodies of the Azov Sea Basin have been investigated. Individuals were examined during their spawning migration in the spring season of 2021. The differences in some physiological and biochemical parameters between the studied samples were considered. It has been found that the content of lipids in the sexual products of males was higher than in the gonads of females, and the protein was lower. Biochemical analysis of fish blood serum showed differences in the level of albumin between females and males and in the amount of triglycerides in the individuals from different fishing sites. In the liver of the fish from the Vostochno-Akhtarskoe (East Akhtarsk) Hatchery, a low activity of all investigated enzymes of the antioxidant system has been recorded.

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