Recruitment, mortality and exploitation rates estimate and stock assessment of Mugil cephalus (Linnaeus, 1758 Mugilidea) in the estuary of the Senegal River
SARR Serigne Modou1,
*KABRE Tinkoudgou Jean-André1 and CECCHI Philippe2
1 Laboratoire de Recherche et de Formation en Pêche et Faune (LaRFPF/ IDR), Université de Bobo-Dioulasso, BP. 1091 Bobo 01, Burkina Faso.
2 Institut de Recherche et Développement (France).
*Corresponding author.
E-mail: ankab226@yahoo.fr
Tel: +22670231734.
The overfishing is the central problem of the Mugil cephalus fisheries in the estuary of the Senegal River. This species lives in the sea during its adult stage but returns in the Senegal River to reproduce and to spend its larval and juvenile stages. This study is aimed to pinpoint the state of exploitation dynamic and to assess the M. cephalus stock. The FISAT II software was used to perform the estimate of recruitment, mortality and exploitation rates. Meanwhile, a virtual population analysis using VIT4 software estimated yield per recruit (Y/R). The analysis yielded exploitation rates E of 0.44 and 0.23 respectively for adult fish and juveniles; therefore the adult stock is overfished during the M. cephalus life stage in sea. In addition, natural mortality (M=1.20 year-1) and total mortality (Z=1.5 year-1) are remarkably high for fish mature age groups III, IV and V. However, in the river the maximum sustainable exploitation (0.50) is not exceeded for juveniles age groups 0+, I and II. In conclusion, management policies should be introduced to safeguard the M. cephalus fishery in the estuary of the Senegal River.
Aspects of Population Dynamics of the Mangrove Oyster, Cassostrea gasar Dautz...Premier Publishers
The study aimed to estimate population parameters of the mangrove oyster, Cassostrea gasar Dautzenberg (1891), such as asymptotic length (L∞), growth coefficient (K), and recruitment pattern and their relationship to environmental factors. 420 samples were measured for standard length and analyzed using FISAT II. Frequency histograms showed the existence of two recruitments per year with a single spawning event occurring at the study sites in May-June at the start of the rainy season when the salinity levels ranged between 10 and 18 ‰. Best growth performances were observed at Lake Zowla with the asymptotic length and growth coefficient reaching 85.10 mm and 10.86g yr-1, respectively. Growth model showed negative allometric growth (b <3), with an asymptotic weight (W∞) of approximately 10.86 g. Oyster reaches an average length of 8.17 cm after 8 months. Results also reveals that the presence of C. gasar in the Zalivé channel and in Lake Zowla is seasonal; indeed, by the end of the little rainy season (end of November), all oyster settlements at both sampling stations were eliminated, and only a few scattered individuals remained. The cycle begins again in December-January the following year with the recruitment of larvae from nearby Aného Lagoon.
Diversity and abundance of terrestrial mammals in the northern periphery of ...Innspub Net
The Tanoé-Ehy Marsh Forest (TEMF), an unprotected forest that is about to be turn into a voluntary nature reserve is a forest block in south-eastern Côte d’Ivoire known as being of great importance for the conservation of biodiversity. But in the rainy season, that forest is largely over flooded and terrestrial mammals are likely to move to the periphery and make them vulnerable to anthropogenic threats. Our objectives are to determine the diversity, the relative abundance of terrestrial mammals and their spatial distribution in the northern periphery of the TEMF during the rainy season. We collected data by conducting recce surveys after interviews with local people. In total, we obtained 33 species among which ten primates’ species were identified. According to the recce survey, the African Civet (Civettictis civetta) and the Bushbuck (Tragelaphus scriptus) are the most common and abundant species in the study area with 12.7% and 12.0% of relative abundance respectively. In addition, six of the listed species are on the IUCN Red List, including Piliocolobus waldronae, a critically endangered species, Cercocebus lunulatus and Cercopithecus roloway endangered species, Colobus vellerosus, Phataginus tetradactyla and Phataginus tricuspis, three vulnerable species. Thus, the consideration of the periphery for the sustainable management of the TEMF is proving to be an imperative.
Spatial Mapping: Diversity and Distribution of Demersal Fish in the Southern ...robert peranginangin
In the future, fisheries management must not be based on biomass measure only, but must use an integrated ecosystem approach. This study was aimed to discover the species diversity level of demersal fish resources in spatial distribution and its relation to the environment. The study was conducted in May and June 2015 by operating a trawl in the assigned stations. The spatial distribution was based on the Bray-Curtis index which divided the distribution of demersal fish resources into three clusters. Inshore sites of Kalimantan’s western waters (KLBR) was dominated by Leognathidae, inshore sites of the eastern of Riau Islands waters (KPRI) was dominated by Lutjanidae, and offshore sites of the southern of South China Sea (SSCS) was dominated by Nemipteridae. Offshore sites of the southern of South China Sea (SSCS) had a much better community stability level than that of inshore sites of Kalimantan’s western waters (KLBR) and inshore sites of the eastern of Riau Islands waters (KPRI). This study also demonstrated that environmental factors such as depth, sediment type, salinity, and temperature, affect the distribution and species diversity of demersal fish communities in the southern of South China Sea.
Aspects of Population Dynamics of the Mangrove Oyster, Cassostrea gasar Dautz...Premier Publishers
The study aimed to estimate population parameters of the mangrove oyster, Cassostrea gasar Dautzenberg (1891), such as asymptotic length (L∞), growth coefficient (K), and recruitment pattern and their relationship to environmental factors. 420 samples were measured for standard length and analyzed using FISAT II. Frequency histograms showed the existence of two recruitments per year with a single spawning event occurring at the study sites in May-June at the start of the rainy season when the salinity levels ranged between 10 and 18 ‰. Best growth performances were observed at Lake Zowla with the asymptotic length and growth coefficient reaching 85.10 mm and 10.86g yr-1, respectively. Growth model showed negative allometric growth (b <3), with an asymptotic weight (W∞) of approximately 10.86 g. Oyster reaches an average length of 8.17 cm after 8 months. Results also reveals that the presence of C. gasar in the Zalivé channel and in Lake Zowla is seasonal; indeed, by the end of the little rainy season (end of November), all oyster settlements at both sampling stations were eliminated, and only a few scattered individuals remained. The cycle begins again in December-January the following year with the recruitment of larvae from nearby Aného Lagoon.
Diversity and abundance of terrestrial mammals in the northern periphery of ...Innspub Net
The Tanoé-Ehy Marsh Forest (TEMF), an unprotected forest that is about to be turn into a voluntary nature reserve is a forest block in south-eastern Côte d’Ivoire known as being of great importance for the conservation of biodiversity. But in the rainy season, that forest is largely over flooded and terrestrial mammals are likely to move to the periphery and make them vulnerable to anthropogenic threats. Our objectives are to determine the diversity, the relative abundance of terrestrial mammals and their spatial distribution in the northern periphery of the TEMF during the rainy season. We collected data by conducting recce surveys after interviews with local people. In total, we obtained 33 species among which ten primates’ species were identified. According to the recce survey, the African Civet (Civettictis civetta) and the Bushbuck (Tragelaphus scriptus) are the most common and abundant species in the study area with 12.7% and 12.0% of relative abundance respectively. In addition, six of the listed species are on the IUCN Red List, including Piliocolobus waldronae, a critically endangered species, Cercocebus lunulatus and Cercopithecus roloway endangered species, Colobus vellerosus, Phataginus tetradactyla and Phataginus tricuspis, three vulnerable species. Thus, the consideration of the periphery for the sustainable management of the TEMF is proving to be an imperative.
Spatial Mapping: Diversity and Distribution of Demersal Fish in the Southern ...robert peranginangin
In the future, fisheries management must not be based on biomass measure only, but must use an integrated ecosystem approach. This study was aimed to discover the species diversity level of demersal fish resources in spatial distribution and its relation to the environment. The study was conducted in May and June 2015 by operating a trawl in the assigned stations. The spatial distribution was based on the Bray-Curtis index which divided the distribution of demersal fish resources into three clusters. Inshore sites of Kalimantan’s western waters (KLBR) was dominated by Leognathidae, inshore sites of the eastern of Riau Islands waters (KPRI) was dominated by Lutjanidae, and offshore sites of the southern of South China Sea (SSCS) was dominated by Nemipteridae. Offshore sites of the southern of South China Sea (SSCS) had a much better community stability level than that of inshore sites of Kalimantan’s western waters (KLBR) and inshore sites of the eastern of Riau Islands waters (KPRI). This study also demonstrated that environmental factors such as depth, sediment type, salinity, and temperature, affect the distribution and species diversity of demersal fish communities in the southern of South China Sea.
Length-weight models and condition factors of fishes from Okpara Stream, Ouem...AI Publications
Length frequency distributions, length-weight models and condition factors of 21 dominant fish species of the Okpara stream (Oueme River) were examined in Northern-Benin in order to evaluate the well-being of these fish taxa. Samplings were made monthly from December 2015 to May 2017 with seines, gill nets hawks and a total of 9,302 individuals were collected. Fish abundance ranged from 53 individuals for Mormyrus rume to 2,818 for Hemichromis fasciatus. Standard length (SL) varied from 1.2 cm (Coptodon guineensis) to 51.8 cm (Chrysichthys nigrodigitatus). Length-weight regressions equations showed significant (p < 0.05) correlation coefficients (r) ranging between 0.4664 and 0.9949 with slopes (b) between 2.2262 and 3.7703 corresponding to isometric, positive allometric and negative allometric growths displayed by 4, 8 and 9 species, respectively. Condition factors K varied between 0.17 - 29.38 and species with higher well-being were Oreochromis niloticus with K=29.38, Hyperopisius bebe (K=20.14), Coptodon zillii (K=19.25), Mormyrus rume (K=17.13) and Sarotherodon galilaeus multifasciatus (K=16.16). A sustainable exploitation of these fishes requires an ecosystem restoration scheme including habitat protection, species conservation and an ecological follow-up of the Okpara stream.
The Growth of Oreochromis niloticus (2.6g initial average size) was studied in 100m2 earthen ponds for 180 days under tropical field environment. Varying fertilizing regimes consisting of Pennisetum purpureum (PP) and Musa sapientum (MS), two locally available weedy grasses were applied in duplicates in the experimental ponds, at the rate of 0.1-0.2 kg dry matter per m2 per day. Water quality parameters were monitored bimonthly between 8:00am-9:00am . Final average fish weight varied significantly (p<0.05) as follows: 43.85g, 35.5g, 59.5g, 24.9g and 50g, 2 respectively for PP, MS, MS+PP, T0 and T1. Corresponding daily growth were 2.2g/d, 0.1g/d, 0.3g/d, 0.1g/d and 0.2g/d. Survival rate equally varied significantly as follow: 60 %, 67 %, and 98 %, 70 % and 97 % respectively. During the study period, the results indicated the water quality were permissibole limits and can be used for livestock of Oreochromis niloticus .
PhD confirmation - ecology of estuarine sharks & rayssharonle
This is a ppt that was used in my confirmation for candidature. It describes how I will use stable isotope and fatty acid analysis to determine what estuarine sharks and rays eat and which areas of the South Alligator River, (NT, Aus) they utilise. This will then inform environmental managers of which areas are critical to the survival of these species.
This study is an attempt to understand the population characteristics such as Length-weight relationships, age, growth, mortality, length at age and exploitation rate of Frigate tuna, Auxis thazard occurring in the North west coast of India. The data collected from various fish landing centers from 2008 to 2012 were considered for this study. The mean fork length and weight 32.35 cm and 1.040 kg were observed respectively. The length-weight relationship W=2.4321x10-1 FL 2.27658, and r2 0.9576 was obtained. The value of ‘b’ found to be less than 3 and hence this species is showing negative allometric growth. The growth parameters on von Bertalanffy for L∞ estimated as 47.03, K was 1.30 and to was -0.23. The Phi-prime value (⏀) of 3.33 was derived. The length at age observed at the end of 1 to 4 years was 27.0, 42.0, 50.0 and 55.0 cm year-1 respectively. The natural mortality (M) 1.00 year-1, total mortality (Z) of 4.43 year-1 and fishing mortality (F) 3.43 year-1 were derived with the mean temperature of 27°C. The exploitation ratio(E) and exploitation rate(U) was 0.77. The results derived in the present study with regard to population characteristics of frigate tuna in the coastal waters of North west coast of India indicate catching of this species in the area to be minimized Key-words- Length-weight relationships, Mortality, Length at age, Exploitation ratio, Exploitation rate
Population structure, fecundity and morphological characteristics of M. vollenhovenii were studied around Lower Volta River, Ghana subject to dirt of information on this prawn species around the study location. The most prominent morphological characteristics already documented for identification of this species was rostrum bearing 13-15 continuous teeth dorsally and 4-5 teeth on its ventral part. These morphological traits formed the principal components for identification in this study. Results showed that morphological traits on second pereiopods such as presence of spines, spinules, teeth borne within the fingers, and dense projections of setae-like features on telson and uropod were observed relevant for identification purposes. Other results revealed that maximum total length recorded in this study (150-155mm) was higher than total length ranges (≤125mm) documented for this species in earlier studies. Consequently, two adult’s classes of prawns were identified (old adult class 81-120mm; and young adults 31-80mm) and older class was observed to be more in catches than the younger prawns. Absolute fecundity revealed that oocytes estimation varied with respect to seasons, ages of prawns and body sizes of specimens examined. In conclusion, this study observed that M. vollenhovenii fishery is operating in a sustainable manner at the time of this study around the study location.
Evaluation of the oyster farming potential of the Cintra bay (southern Morocco)Origins publication
The bay of Cintra is a marine ecosystem located in the southern Moroccan Atlantic known for its
biological richness and therefore for its high fishery productivity. This bay was chosen as a new destination for the
development of aquaculture in the southern regions of Morocco. To highlight its potential in terms of oyster
farming, a first rearing trial of triploid cupped oysters (Crassostrea gigas) as well as parallel monitoring of the
phytoplankton population and ecological parameters were undertaken. The results obtained showed that the oysters
adapt well to the conditions of the new environment where mortality was negligible, or even absent after a month
of launching. In terms of biological performance, the growth of individuals is continuous during the annual cycle
and after eight months the weight could reach 30.5 g which is a minimum weight for marketing. The AFNOR and
Lawrence and Scott indices showed a good physiological state and a better commercial quality of the oysters. The
filling rate of these oysters, with an average weight of 39.7g when lifting, is very high according to the Lawrence and
Scott index (126.3) and the average AFNOR index (around 21.8) rank them in the “Special” category.
Length Frequency Distribution, Length-Weight Relationship and Condition Facto...paperpublications3
Abstract: Length –Frequency Distribution, Length – Weight relationship and condition factor of Pomadasys jubelini from the Lagos lagoon were investigated for 6months in order to study the growth pattern and wellbeing of P.jubelini. A total of 305 specimens of P.jubelini were purchased from local fisher-folks on landing sites at different locations within the Lagos lagoon ( Majidun, Makoko, Ibese, Bayeiku) from January 2012 to June 2012 and used for this study. Their Total length ranging from 12cm to 29.5cm and body weight ranged from 21.3g to 367g. The frequency distribution showed a polymodal distribution of P.jubelini. The size class of 18.0cm to 20.9cm (TL) was more abundant. The length weight relationship was determined by regression coefficient equation Log W= -1.8357+2.9628LogL (n =305, r = 0.9213). P.jubelini showed negative allometric growth (b= 2.96). The mean condition factor 1.31, indicates that P.jubelini were in good condition in the lagoon. The result from this study is relevant for fishery management and stock assessment studies of P.jubelini from the Lagos lagoon.
Tovacov lakes, and the whole area affected by mining, represents a very important refuge for many rare species of plants and animals that can’t find suitable living conditions in the surrounding intensively farmed landscape. Due to the high level of underground water and the presence of gravel bed, Tovacov lakes can be very important wetlands but also interesting xerotherm habitat in the future. Our aim is not only to identify this biodiversity, but also to support it in the future by targeted interventions.
In the first phase of the project large field survey of different habitats were carried out. These surveys will be focused on characteristic areas that differ in moisture, age and the way they were created. Apart from vascular plants and vegetation, we will be focused on major groups of organisms for which such habitats are essential and at the same time there isn’t enough historical data. These are mainly beetles, butterflies and spiders, but other groups of animals will not be left out.
In the second phase a comparison of diversity of locally rare species with their representation in the various habitats was completed. In this way the mapping of biologically valuable sites and habitats that create appropriate conditions for the occurrence of target species is done.
In the third part, created design principles of management for such areas that will support the best possible future existence of discovered organisms and will create suitable biotopes for other types of communities of plants and animals.
The project won the International contest of the Quarry Life Award 2014 in the category “Biodiversity Enhancement”
Read more: http://www.quarrylifeaward.com/project/research-biodiversity-tovacov-lakes
The present study aims to investigate the biodiversity of woody vegetation along a gradient of human impacting region in the three constituent parts of Ferlo Biosphere Reserve (FBR): the core area, the buffer zone and the transition area. We conducted an inventory of 110 plots of 900 m² each. Total species richness was 49 species distributed in 32 genera within 16 botanical families. The analysis of contesimal frequency showed that Guiera senegalensis is the most common species with a presence of 75% of such records. Examination of species abundance spectrum showed that four most abundant species such as Guiera senegalensis (29.5%), Combretum glutinosum (15.9%), Pterocarpus lucens (11.6%) and Boscia senegalensis (10 , 5%). These four species represent 68% of the total individuals of the RBF and are also the four most common species. The spectrum of abundance of families showed that Combretaceae is the best represented family with almost half of the number of species (49.7%). The representativeness of biological types and geographical affinity of the species has been established for the woody vegetation in the study area. The study of diversity indices revealed that the buffer zone and the transition area are subjected to multiple uses and experiencing human action. It has a greater diversity and a level of organization with higher timber stand than the central area which is an integral conservation zone.
Length-weight models and condition factors of fishes from Okpara Stream, Ouem...AI Publications
Length frequency distributions, length-weight models and condition factors of 21 dominant fish species of the Okpara stream (Oueme River) were examined in Northern-Benin in order to evaluate the well-being of these fish taxa. Samplings were made monthly from December 2015 to May 2017 with seines, gill nets hawks and a total of 9,302 individuals were collected. Fish abundance ranged from 53 individuals for Mormyrus rume to 2,818 for Hemichromis fasciatus. Standard length (SL) varied from 1.2 cm (Coptodon guineensis) to 51.8 cm (Chrysichthys nigrodigitatus). Length-weight regressions equations showed significant (p < 0.05) correlation coefficients (r) ranging between 0.4664 and 0.9949 with slopes (b) between 2.2262 and 3.7703 corresponding to isometric, positive allometric and negative allometric growths displayed by 4, 8 and 9 species, respectively. Condition factors K varied between 0.17 - 29.38 and species with higher well-being were Oreochromis niloticus with K=29.38, Hyperopisius bebe (K=20.14), Coptodon zillii (K=19.25), Mormyrus rume (K=17.13) and Sarotherodon galilaeus multifasciatus (K=16.16). A sustainable exploitation of these fishes requires an ecosystem restoration scheme including habitat protection, species conservation and an ecological follow-up of the Okpara stream.
The Growth of Oreochromis niloticus (2.6g initial average size) was studied in 100m2 earthen ponds for 180 days under tropical field environment. Varying fertilizing regimes consisting of Pennisetum purpureum (PP) and Musa sapientum (MS), two locally available weedy grasses were applied in duplicates in the experimental ponds, at the rate of 0.1-0.2 kg dry matter per m2 per day. Water quality parameters were monitored bimonthly between 8:00am-9:00am . Final average fish weight varied significantly (p<0.05) as follows: 43.85g, 35.5g, 59.5g, 24.9g and 50g, 2 respectively for PP, MS, MS+PP, T0 and T1. Corresponding daily growth were 2.2g/d, 0.1g/d, 0.3g/d, 0.1g/d and 0.2g/d. Survival rate equally varied significantly as follow: 60 %, 67 %, and 98 %, 70 % and 97 % respectively. During the study period, the results indicated the water quality were permissibole limits and can be used for livestock of Oreochromis niloticus .
PhD confirmation - ecology of estuarine sharks & rayssharonle
This is a ppt that was used in my confirmation for candidature. It describes how I will use stable isotope and fatty acid analysis to determine what estuarine sharks and rays eat and which areas of the South Alligator River, (NT, Aus) they utilise. This will then inform environmental managers of which areas are critical to the survival of these species.
This study is an attempt to understand the population characteristics such as Length-weight relationships, age, growth, mortality, length at age and exploitation rate of Frigate tuna, Auxis thazard occurring in the North west coast of India. The data collected from various fish landing centers from 2008 to 2012 were considered for this study. The mean fork length and weight 32.35 cm and 1.040 kg were observed respectively. The length-weight relationship W=2.4321x10-1 FL 2.27658, and r2 0.9576 was obtained. The value of ‘b’ found to be less than 3 and hence this species is showing negative allometric growth. The growth parameters on von Bertalanffy for L∞ estimated as 47.03, K was 1.30 and to was -0.23. The Phi-prime value (⏀) of 3.33 was derived. The length at age observed at the end of 1 to 4 years was 27.0, 42.0, 50.0 and 55.0 cm year-1 respectively. The natural mortality (M) 1.00 year-1, total mortality (Z) of 4.43 year-1 and fishing mortality (F) 3.43 year-1 were derived with the mean temperature of 27°C. The exploitation ratio(E) and exploitation rate(U) was 0.77. The results derived in the present study with regard to population characteristics of frigate tuna in the coastal waters of North west coast of India indicate catching of this species in the area to be minimized Key-words- Length-weight relationships, Mortality, Length at age, Exploitation ratio, Exploitation rate
Population structure, fecundity and morphological characteristics of M. vollenhovenii were studied around Lower Volta River, Ghana subject to dirt of information on this prawn species around the study location. The most prominent morphological characteristics already documented for identification of this species was rostrum bearing 13-15 continuous teeth dorsally and 4-5 teeth on its ventral part. These morphological traits formed the principal components for identification in this study. Results showed that morphological traits on second pereiopods such as presence of spines, spinules, teeth borne within the fingers, and dense projections of setae-like features on telson and uropod were observed relevant for identification purposes. Other results revealed that maximum total length recorded in this study (150-155mm) was higher than total length ranges (≤125mm) documented for this species in earlier studies. Consequently, two adult’s classes of prawns were identified (old adult class 81-120mm; and young adults 31-80mm) and older class was observed to be more in catches than the younger prawns. Absolute fecundity revealed that oocytes estimation varied with respect to seasons, ages of prawns and body sizes of specimens examined. In conclusion, this study observed that M. vollenhovenii fishery is operating in a sustainable manner at the time of this study around the study location.
Evaluation of the oyster farming potential of the Cintra bay (southern Morocco)Origins publication
The bay of Cintra is a marine ecosystem located in the southern Moroccan Atlantic known for its
biological richness and therefore for its high fishery productivity. This bay was chosen as a new destination for the
development of aquaculture in the southern regions of Morocco. To highlight its potential in terms of oyster
farming, a first rearing trial of triploid cupped oysters (Crassostrea gigas) as well as parallel monitoring of the
phytoplankton population and ecological parameters were undertaken. The results obtained showed that the oysters
adapt well to the conditions of the new environment where mortality was negligible, or even absent after a month
of launching. In terms of biological performance, the growth of individuals is continuous during the annual cycle
and after eight months the weight could reach 30.5 g which is a minimum weight for marketing. The AFNOR and
Lawrence and Scott indices showed a good physiological state and a better commercial quality of the oysters. The
filling rate of these oysters, with an average weight of 39.7g when lifting, is very high according to the Lawrence and
Scott index (126.3) and the average AFNOR index (around 21.8) rank them in the “Special” category.
Length Frequency Distribution, Length-Weight Relationship and Condition Facto...paperpublications3
Abstract: Length –Frequency Distribution, Length – Weight relationship and condition factor of Pomadasys jubelini from the Lagos lagoon were investigated for 6months in order to study the growth pattern and wellbeing of P.jubelini. A total of 305 specimens of P.jubelini were purchased from local fisher-folks on landing sites at different locations within the Lagos lagoon ( Majidun, Makoko, Ibese, Bayeiku) from January 2012 to June 2012 and used for this study. Their Total length ranging from 12cm to 29.5cm and body weight ranged from 21.3g to 367g. The frequency distribution showed a polymodal distribution of P.jubelini. The size class of 18.0cm to 20.9cm (TL) was more abundant. The length weight relationship was determined by regression coefficient equation Log W= -1.8357+2.9628LogL (n =305, r = 0.9213). P.jubelini showed negative allometric growth (b= 2.96). The mean condition factor 1.31, indicates that P.jubelini were in good condition in the lagoon. The result from this study is relevant for fishery management and stock assessment studies of P.jubelini from the Lagos lagoon.
Tovacov lakes, and the whole area affected by mining, represents a very important refuge for many rare species of plants and animals that can’t find suitable living conditions in the surrounding intensively farmed landscape. Due to the high level of underground water and the presence of gravel bed, Tovacov lakes can be very important wetlands but also interesting xerotherm habitat in the future. Our aim is not only to identify this biodiversity, but also to support it in the future by targeted interventions.
In the first phase of the project large field survey of different habitats were carried out. These surveys will be focused on characteristic areas that differ in moisture, age and the way they were created. Apart from vascular plants and vegetation, we will be focused on major groups of organisms for which such habitats are essential and at the same time there isn’t enough historical data. These are mainly beetles, butterflies and spiders, but other groups of animals will not be left out.
In the second phase a comparison of diversity of locally rare species with their representation in the various habitats was completed. In this way the mapping of biologically valuable sites and habitats that create appropriate conditions for the occurrence of target species is done.
In the third part, created design principles of management for such areas that will support the best possible future existence of discovered organisms and will create suitable biotopes for other types of communities of plants and animals.
The project won the International contest of the Quarry Life Award 2014 in the category “Biodiversity Enhancement”
Read more: http://www.quarrylifeaward.com/project/research-biodiversity-tovacov-lakes
The present study aims to investigate the biodiversity of woody vegetation along a gradient of human impacting region in the three constituent parts of Ferlo Biosphere Reserve (FBR): the core area, the buffer zone and the transition area. We conducted an inventory of 110 plots of 900 m² each. Total species richness was 49 species distributed in 32 genera within 16 botanical families. The analysis of contesimal frequency showed that Guiera senegalensis is the most common species with a presence of 75% of such records. Examination of species abundance spectrum showed that four most abundant species such as Guiera senegalensis (29.5%), Combretum glutinosum (15.9%), Pterocarpus lucens (11.6%) and Boscia senegalensis (10 , 5%). These four species represent 68% of the total individuals of the RBF and are also the four most common species. The spectrum of abundance of families showed that Combretaceae is the best represented family with almost half of the number of species (49.7%). The representativeness of biological types and geographical affinity of the species has been established for the woody vegetation in the study area. The study of diversity indices revealed that the buffer zone and the transition area are subjected to multiple uses and experiencing human action. It has a greater diversity and a level of organization with higher timber stand than the central area which is an integral conservation zone.
Inclusive design. It might sound like a rebranding exercise from the Web Accessibility Marketing Team, but it isn’t. For years inclusive design and research practices have been applied to a wide variety of disciplines from industrial design to the arts, the built environment and more.
What can we learn from this? And how can we apply it to the digital environment in which we work?
Social innovation, service design and even augmented reality are now presenting real and interesting opportunities for us as traditional web practitioners. Combined with inclusive design practices, this opens up a fantastic world of change for both us and the people for whom we design.
Discussion paper for the 4th regional public internal financial control conference for EU Enlargement countries, organised by SIGMA and co-hosted by the Ministry of Finance of Montenegro, that took place in Becici, Montenegro on 29-30 September 2016.
Rear Admiral (Retired) Rapp looks at the role of LVC trainingICSA, LLC
In a presentation to a Williams Foundation seminar on August 10, 2016, Rear Admiral (Retired) James Rapp looked at the evolving and expanding role of LVC training.
The Williams Foundation has held a seminar on new approaches to air-sea integration on August 10, 2016 in Canberra, Australia.
The Royal Australian Navy has had the ability to network and share situational awareness amongst the fleet for many years and the P-3s has been the only RAAF platform capable of being part of that network. The RAAF’s journey of networking its capability journey started more recently with the Hornet Upgrade Program and has accelerated with the introduction of capabilities like Wedgetail and Vigilaire. All of the RAAF’s fleet is now capable of linking into and contributing to an Air Layer of the Joint Battle management system.
With the advent of 5th Generation capabilities like the JSF and the new combat systems on the AWD as well as the design and development of the new combat systems for the Australia’s future frigates, Offshore Patrol vessels and Submarines, the ADF has a unique opportunity to influence and design in an unprecedented level of integration into the RAN’s and RAAF’s new platforms. That unprecedented level of integration should drive new thinking on the integration of air and sea power effects. The seminar is about examining the challenges and possibilities of the combat power in that future integrated force.
Air Force and Navy need to not only remediate existing deficiencies but take advantage of the transformative nature of fifth generation technology. The seminar aims to explore the art of the possible in future Air-Sea operations.
http://www.williamsfoundation.org.au/event-2230289
Transforming the Distributor Network with SAP Fiori and MFGPathCapgemini
United Copper Industries (UCI) is a leader in the copper wire sector. Hear how UCI leveraged the pre-configured MFGPath, a qualified SAP Business All-in-One partner solution, along with the SAP Fiori user experience, to reengineer business processes for pricing and its distributor channel.
Presented at SAPPHIRE NOW 2016.
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Freshwater fish diversity of a tropical rainforest river in southeast nigeriaAlexander Decker
The International Institute for Science, Technology and Education (IISTE). Science, Technology and Medicine Journals Call for Academic Manuscripts
Similar to Recruitment, mortality and exploitation rates estimate and stock assessment of Mugil cephalus (Linnaeus, 1758 Mugilidea) in the estuary of the Senegal River (20)
Freshwater fish diversity of a tropical rainforest river in southeast nigeria
Recruitment, mortality and exploitation rates estimate and stock assessment of Mugil cephalus (Linnaeus, 1758 Mugilidea) in the estuary of the Senegal River
2. Int. J. Agric. Policy Res. 002
Figure 1. Map of Senegal River showing the sampling site
Data collection Nt =N0e-Zt
Weekly random samplings were conducted to collect data ln(N) = a + b · t’
on M. cephalus between January 2011 and March 2012,
producing 1665 fish of which 1243 juveniles collected in N is the number of fish in (pseudo) cohorts "sliced" by
the river and 422 specimens caught at sea (245 females and successive growth curves which is the relative age of the
177 males, all measured (TL, m), weighed (g) and sexed. fish in this pseudo cohort, while b, with the sign changed,
The creel survey on site consisted of 36 interviews over 3 provides an estimate of Z.
months on 12 groups of fishermen, recording their catches.
Natural mortality (M) and exploitation rate
Statistical analysis of data
The empirical method of Pauly (1980; 1984) has been used
The software used for data processing was FiSAT II for the evaluation of the natural mortality of pelagic fish,
(Gayanilo et al., 2005) and it enabled the estimation of the since it fits better than the other input methods (Djabali
exploitation parameters of M. cephalus related to total et al., 1993).
mortality (Z), natural mortality (M), fishing mortality (F),
exploitation rate (E) and recruitment rate; while virtual log10 (M) = -0.0066 - 0.279 log10 (L∞) + 0.6543 log10 (K) +
population analysis (VPA) was used for stock assessment. 0.4634 log10 (T°)
In addition to these computation, the routines embedded in
FiSAT II and VIT4 (FAO, 1997) required the estimation of L∞ = asymptotic length, K = growth coefficient and T =
von Bertalanffy growth parameters (Sarr et al., 2012). average temperature of habitat (°C).
Total mortality Z Once Z and M were obtained, the fishing mortality (F) was
estimated using the equation:
Total mortality (Z) was estimated by the method
called "length-based catch curves". The speed at which the F=Z–M
dN / dt = - Zt Finally the exploitation rate (E) was obtained from:
The number of fish surviving at a given time, Nt, is: E = F/Z = F/(F + M).
3. Sarr et al. 003
Recruitment impact of a change in fishing effort after determining
mortality coefficients and therefore responsible for
Recruitment was obtained using the length frequency data providing fisheries information actual stock status.
using software FiSATII. The routine reconstructs the In the software FiSAT II, this model combines elements of
rhythms of recruitment from a time series of length the model Y'/R of Beverton and Holt with those of VPA; it
frequency data. The recruitment model is obtained by reverses. The sum of the yields is:
projecting the length frequency data back on the time axis
using the growth parameters (Moreau and Cuende, 1991). Y = Yi and Yi=Ci.W’i
Virtual Population Analysis The average weight of the body is given as:
The Virtual Population Analysis (VPA), also called Wi’= (1/Li+1-Li)(a/b+1)(Li+1b+1;Lib+1)
sequential analysis and cohort analysis, is one of the most
widely used methods of the structural approach (Gascuel et Where a and b are the coefficients of the length-weight
al, 2007). VPA is a method that allows the reconstruction of relationship; Li and Li+1 are respectively the lower and
the population from the total catch data by age or size. upper limits of the size class.
Ci = (Ni-Ni+1)(Fi/(M+Fi))
Stock assessment
The predicted population (Ni) is given by:
Analysis of the relative performance recruits (Y/R) and
biomass recruits (B/R) Ni+1 = Ni · EXP (-(M+Fi) ·∆ti) and
Beverton and Holt (1966) express the relative yield per ∆ti = (1/K) ln ((L∞-Li)/(L∞-Li+1))
recruit (Y'/R), to determine the relationship between yield
and fishing effort for different sizes of first capture. It Biomass is calculated from:
belongs to the class of models based on length. Expression
of Y'/R is: Bi=((Ni-N1+1)/(M+Fi)).∆ti.Wi’.
Y’/R=EUM/K[ 1- 3U/(1+m) + 3U2/(1+2m)-U3(1+m)]
Where: U=1-(LC/L∞); m= (1-E)/(M /K) = (K /Z); E=F/Z RESULTS
LC= average fish size at first capture, equivalent to L 50 Parameters of mortality and exploitation rates
average fish size at first capture; m = mesh size
Different mortality parameters are given by the length-
Biomass per recruit relative (B'/R) is estimated from the converted catch curve for males and females captured at
relationship: sea and juveniles caught in the river.
For males: Z = 2.06yr-1, M = 1.24 yr-1, F = 0.82 yr-1 and E =
B'/R = (Y'/R)/F 0.40 (Figures 2 and 3). To determine the natural mortality
(M), the empirical equation of Pauly (1980) was employed
While Emax, E10 and E50 are estimated using the first considering an annual average temperature of 22.5°C thus:
derivative of this function
log (M) =-0.0066 - 0.279 log(L∞) + 0.6543 log(K) + 0.4634
E10= level of exploitation at which the marginal increase in log(T).
yield per recruit reaches 1/10 of the marginal increase
computed at a very low value of E; E50= exploitation level Mortalities by age and sex are shown in Table 1. The total
which will result in a reduction of the unexploited biomass mortality Z, natural mortality M, fishing mortality F and
by 50%; Emax= exploitation level which maximizes Y/R or exploitation rates E are presented in Table 2. Fishing
Y'/R. mortality is higher in adults than in juveniles. The juveniles
group natural mortality is very high compared to mature
fish. In Table 3, the mortality rates resulting from this study
Predictive model of Thompson and Bell (1934)
may be compared to those of former studies.
The model of Thompson and Bell (1934) is used to predict
the effects of changes in fishing effort on future production Recruitment
and biomass from the historical data of fishery. The latter
is based on the analysis of pseudo-cohorts to assess the The estimated rate of recruitment is shown in Figure 4 and
4. Int. J. Agric. Policy Res. 004
Figure 2. Length-converted catch curve for (males of Mugil cephalus in the Senegal River.
Z=2.06; M (at 22.0°C)=1.24; F=0.82;E=0.40) (Z = total mortality, M = natural mortality, F=
fishing mortality, E= exploitation rate).
Figure 3. Length-converted catch curve for females of Mugil cephalus in the Senegal River.
Z=2.09; M (at 22.5°C)=1.17; F=0.92; E=0.44) (Z =total mortality, M = natural mortality, F=
fishing mortality, E= exploitation rate).
5. Sarr et al. 005
Table 1. Natural mortality of Mugil cephalus for each age group in the Senegal
River (T=22.5°C).
Age (year) TL (cm) L∞ (cm) K (year-1) M (year-1)
0+ 23.81 67.6 0.43 1.20
I 33.05 68.78 0.42 1.20
II 38.21 68.78 0.42 1.24
III 50.35 73.09 0.32 1.20
IV 60.29 73.44 0.31 1.18
V+ 61.17 73.44 0.31 1.17
Table 2. Mugil cephalus exploitation rates by sex in the Senegal River.
Sex Z( year-1) M( year-1) F = Z – M(year-1) E=F/Z Z/K M/K
Females 2.09 1.17 0.92 0.44 6.52 3.65
Males 2.06 1.24 0.82 0.40 6.46 3.87
Juveniles 1.55 1.20 0.35 0.23 3.69 2.85
Table 3. Parameters of mortality computed for Mugil cephalus by various authors.
Author Zone Z (year-1) M(year-1) F(year-1) E(year-1)
Zhang (2006) Korea 0.516
Ibáňez-Aguirre and Garlando-Cabello (1996) Tropical Lagoon, México 0.27 0.114 0.126 0.466
Katselis et al. (2010) Greece 1.59 0.34 1.25 0.78
Rathacharen et al. (1999) Coastal areas of Mauritius 1.65 0.53 1.12 0.67
Uneke et al. (2010) Nigeria 4.03 2.77 1.26 0.31
Djabali et al. (1993) Mediterranean Sea 0.17
Figure 4. Length-converted catch curve for juveniles of Mugil cephalus in the
Senegal River Z=1.55; M(at 22.5°C)=1.20; F=0.35;E=0.23) (Z = total mortality,
M=natural mortality, F= fishing mortality,E=exploitation rate).
6. Int. J. Agric. Policy Res. 006
5. The annual recruitment model revealed one phase. It
lasts all the year (January to December) over the three
consecutive months of great recruitment, the office
plurality of percentage varied.
STOCK ASSESSMENT
Analysis of relative performance recruits (Y’/R) and
biomass recruits (B’/R) following Beverton and Holt
(1966)
In Figure 6 and 7, the model of Beverton and Holt (1966) as
modified by Pauly and Soriano (1986) was used to predict
Figure 5. Recruitment curve for Mugil cephalus in the fisheries the relative yield per recruit (Y'/R) of M. cephalus. Plots
along the Senegal River. (Y'/R) and (B'/R) as a function of exploitation rate E were
used to estimate E-max (exploitation rate producing the
maximum yield), E-10=0.355 (rate operation during which
the marginal increase (Y'/R) is 10% of the virgin stock) and
E-50=0.278 (the rate of exploitation under which the stock
is reduced to half of its virgin biomass). These exploitation
rates were calculated by the derivative function of the
expression of yield per recruit (Y/R) and are reported in
Table 4.
For different sizes of first capture Lc and the rate of
operation E, the relative performance per recruit Y'/ R
increases to a maximum and then decreases. The ma-
ximum allowable exploitation rates E-max = 0.42 of 0.44 for
females and 0.40 for males. The optimum level of relative
performance by rookie is reached. The species is overfished
in the locality.
Figure 6. Histogram of the virtual population of Mugil cephalus in the Predictive model of Thompson and Bell (1936)
Senegal River.
The model shows the maximum sustainable yield (MSY),
maximum sustainable economic production (MSE), the f-
factor and the corresponding biomass (Figure 8).
For M. cephalus, the f-factor value of 1.8 corresponds to
the MSY while the MSE is obtained with an f-factor of 2.0.
The results show that the level of fishing effort is higher
than that corresponding to the MSE.
DISCUSSIONS
Fishing mortality (F) and natural mortality (M) contribute
to the total mortality (Z). In addition, growth and mortality
are antagonistic. According to Barry and Tegner (1989), the
predominance of growth on mortality can be perceived by
the ratio Z/K being less than 1; a ratio greater than 1 means
that the stock is collapsing; if the ratio is equal to 1, the
population is in a steady state; finally, if this proportion is
Figure 7. Curve of yield and relative biomass by recruit (knife–edge much higher than 2, the stock is overexploited. The total
selection) for Mugil cephalus in the Senegal River. The values of Y'/R mortalities are respectively 2.06 and 2.09 year-1 for males
and B’/R are respectively 30 and 700g. and females caught at sea, while they are lower in juveniles
7. Sarr et al. 007
Figure 8. Thompson and Bell yield stock prediction of Mugil cephalus in
estuary of the Senegal River.
juveniles (Z = 1.55 year-1) from the river. The ratio Z/K is indicates a strong pressure while fishing at sea for yellow
6.52 for females, 6.46 for males and 3.65 for juveniles it mullets. Our results on total and natural mortalities of M.
shows overuse of M. cephalus in the sea and in the estuary cephalus, compared with those of Rathacharen and
of the Senegal River. Big fish as well as juveniles are under al.(1999) in Mauritius (Table 3) and of did not show
pressure and this can lead to long stocks a fuck. significant differences because χ 2 calculated = 0.745 < χ 2
According to Beverton and Holt (1959), the ratio M / K theoretical = 3.81; p = 0,05. By against the values of Z and M
determines the level of fish mortality. If this ratio is (Table 3) found in Nigeria Uneke et al. (2010) are very high
between 1.5 and 2.5, the threshold is not exceeded permitted. compared to our results. This difference can be explained
The values of M/K for M. cephalus in the estuary of the by a very high fishing effort and a high natural mortality.
Senegal River are between 2.85 and 3.87 (Table 2). Natural The results of this study show different levels of
mortality is higher for age groups 0+ and I, II (M = 1.20 year- exploitation. For the case of females (E = 0.44) and males (E
1). These natural mortalities decrease with age groups III, = 0.4 caught at sea, the critical threshold (0.50) is not
IV, V and are about 1.18 year-1. These results could be exceeded for M. cephalus in Senegal River , thus suggesting
explained by a high predation or other natural causes overexploitation of M. cephalus of ages between 3 and 5
affecting fry and juveniles. Mortality parameters depend on years. By contrast optimum performance is not achieved for
both physiological factors (disease, old age, etc.), juveniles (E = 0.23) caught in the river. This situation is
environmental factors (temperature, currents ...). According described by Froese (2004) as recruitment overfishing;
to Christensen and Pauly (1997) for juveniles, predation other fish are caught before they can realize their full
mortality is sometimes much higher than fishing mortality. potential. . The effort of fishing is more intense on the sea
The results of this paper were compared with those level. The gravidic females are targeted by the fishermen
obtained by several other studies (Table 3). The for the gonades which will be transformed and sented in
comparison shows that the mortality estimates differ from Europe. Increase in the biomass by recruit entrain a
author to author and from one region to another, the reduction in the reproductive biomass (Table 4). The curve
temperature of the environment and the parameters of the of recruitment (Figure 5) is smoothed by two normal
equation of von Bertalanffy are the main sources of curves at end to allow a better visualization of the peak.
variation values of natural mortality (Pauly, 1985). Broadly the period of recruitment is between May and
The comparison between the fishing mortality (0.92 April. And the office plurality of the percentage of
year-1 for females and 0.82 year-1 for males ) and natural recruitment is 43.87%.
mortality (1.17year-1 for females and 1.24 year-1 for males) The peak is observed during the dry season, during which
8. Int. J. Agric. Policy Res. 008
Table 4. Values of yield, biomass and reproductive biomass by
recruit of Mugil cephalus in the Senegal River.
Y'/R= 30 g E-max=0.476
E-50=0.287 M/K= 1.74
E-10=0.42 B’/R=700 g
Factor Y/R B/R SSB
0 0 10.559 5.37
0.01 0.026 10.506 5.329
0.02 0.051 10.454 5.287
0.03 0.076 10.403 5.246
0.04 0.1 10.351 5.206
0.05 0.124 10.3 5.165
0.06 0.148 10.25 5.125
0.07 0.172 10.199 5.086
0.08 0.195 10.149 5.046
0.09 0.218 10.1 5.008
0.1 0.241 10.051 4.969
0.2 0.453 9.58 4.601
0.3 0.64 9.142 4.265
0.4 0.804 8.735 3.956
0.5 0.949 8.356 3.672
0.6 1.078 8.003 3.412
0.7 1.191 7.672 3.172
0.8 1.291 7.364 2.951
0.9 1.379 7.075 2.748
1 1.457 6.804 2.56
1.1 1.526 6.55 2.387
1.2 1.588 6.311 2.227
1.3 1.642 6.086 2.079
1.4 1.69 5.874 1.942
1.5 1.732 5.675 1.816
1.6 1.77 5.486 1.698
1.7 1.803 5.308 1.589
1.8 1.833 5.14 1.488
1.9 1.859 4.98 1.394
2 1.881 4.829 1.306
the water is brackish. Yellow mullets would develop Senegal River Estuary are 69.32 g respectively and 54.72 g
strategies to match the period of larval emergence at a time (Table 4). Figure 7 shows that the relative yield per recruit
when environmental factors could offer a better chance of has reached its maximum Y'/R = 30 g biomass per recruit
survival. The length-based virtual population analysis with B'/R = 700 g for maximum exploitation rate (E-max =
(Figure 6) showed that the fishing mortality gradually 0.476). The best yields were obtained for E between 0.4 and
increased with size, contrary to the natural mortality, i.e. 0.7.
the probability of capture increases with age, and the more For the relative yield per recruit and the relative biomass
mature are the fishes, the more they are caught. Recruit- per recruit, our results are different from those obtained by
ment and growth have contributed to gains respectively Katselis et al(2010) in Greece for M. cephalus. The latter
11.46% and 88.54%. The average total number of found Y'/R = 25g and B'/R = 275g for E-max=0.38. The
individuals was estimated at 2117700 individuals and the analysis of yield per recruit (Y/R) showed that the current
total biomass specimens average about 300.731103 kg. This level of exploitation far exceeds the level of maximum
biomass is mainly composed of individuals whose size sustainable yield. The stock of M. cephalus in the Senegal
classes vary 17 cm to 64 cm and represents 76.98% of the River Estuary is overfished with fishing effort mainly
total stock biomass exploited. The average length of the directed towards the mature fish. The results show that the
critical current stock is 40 cm and the mean age of the level of fishing effort is higher than that corresponding to
current stock is 2.48 years. Biomass renewed (298.711 103 the MSE. This indicates that the exploitation of this stock
kg ) is less than the biomass produced (457.751103 kg ). exceeds its optimum level, and for that reference to the
The renewal of the stock is slow compared to the catch cohort analysis, it may be appropriate to reduce fishing
intensity of M. cephalus in the estuary of the Senegal River. effort and to found a biological rest each year. The
Yield and biomass per recruit (Y/R and B/R) mules in the Thompson and Bell (1936) model confirms the results
9. Sarr et al. 009
obtained by the exploitation rate relative yield per recruit des stocks II (FiSAT II).
and relative biomass by the Beverton and Holt (1966) Version révisée. Guide d’utilisation, FAO Série informatique.
method. Pêche (8) :190.
Gascuel D, Zeller DO, Talib Sidi M, Pauly D (2007).
Reconstructed catches in the Mauritanian EEZ. In: Zeller
CONCLUSION D, Pauly D (eds.), Reconstruction of Marine Fisheries
Catches for Key Countries and Regions (1950-2005).
In the Grande Côte in Senegal, yellow mullet are mainly Fisheries Centre research Report 15(2) : 105-119
exploited by artisanal fishing which takes large specimens Ibáňez-Aguirre AL, Garllado- Cabello M (1996). Total and
(E= 0.44) at sea and juveniles in the river (E=0.23 ). For this natural mortality of Mugil cephalus and Mugil curema
type of operation almost any age of the exploit table phase (Pisces : Mugilidea), in Tamiahua Lagoon, Veracruz. I.
is unaffected. The stock of M. cephalus in the Senegal River selectivity. Hydrobiological, 6(1-2): 9-16.
Estuary is overfished with fishing effort directed towards Katselis G, Koukou K, Moutopoulos D (2010). Yield per
the mature fish. The renewed biomass (278.71 103 kg) is recruit and spawning stock biomass models for the
lower than the produced biomass (457.75 103 kg), showing management of four Mugilidae species in Mesolonghi –
the state of overexploitation of the fish stock, with the level Aitoliko Lagoon (W. Greece). Int. Aquat. Res., 2:155-162.
of fishing effort higher than that corresponding to the MSE. Lawson EO, Abayomi AAJ (2010). Aspects of the biology of
It is concluded from this study that the yellow mullet grey mullet, Mugil cephalus, in Lagos lagoon,Nigeria.
fisheries in maritime and river Senegal are overexploited. Department of Fisheries, Faculty of Science, Lagos State
The decrease in fishing effort for the species M. cephalus University, Ojo, Lagos, Nigeria, AACL Bioflux,(3): 181-194.
will help maintain the state of stocks. Moreau J, Cuende FX (1991). On improving the resolution of
the recruitment patterns of fishes. ICLARM Fishbyte, 9:
45-46.
ACKNOWLEDGMENTS Okumuş Ȋ, Başçnar N (1997). Population structure, growth
and reproduction of introduced Pacific mullet, Mugil
We are grateful to the Office of Cooperation and Cultural soiuy, in the Black Sea. Fisheries Res., 33: 131-137.
Action of the France Embassy in Senegal, which supported Pauly D (1980). On the interrelationships between natural
this research work. mortality, growth parameters and mean environmental
temperature in 175 fish stocks. J. du Conseil Inter. pour
l’Exploration de la Mer., 39: 175-192.
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