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This work aims to the effect of three different concentrations (20%, 40%, and 60%) of Ocimum gratissimum extract on the proximate, mineral composition and sensory acceptability of smoked catfish and mackerel samples. Fresh fish samples were hot smoked in a locally fabricated smoking kiln at 1100C. Results showed that the moisture content of smoked catfish and mackerel was significantly different (P≤0.05) from the control sample. The percentage of crude protein content decreased in smoked catfish and increased in mackerel samples and also differed significantly (P≤0.05) compared with the control. Ash and fat content decreased in smoked fish and the crude fibre content was slightly increased in smoked mackerel. The minerals composition showed a significant difference (P≤0.05) was observed although there were decrease in iodine and potassium content of catfish. There was a significant difference (P≤0.05) in organoleptic scores among the fish samples treated with 20% and 40% Ocimum gratissimum which were significantly higher than the control. This study concluded that Ocimum gratissimum inclusion does not have any adverse effect on the chemical composition of smoked fish sample but could improve their sensory quality.
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Aims@#The aim of this study was to screen lactic acid bacteria (LAB) isolates with probiotic properties for tilapia (Oreochromis niloticus) from the intestines of mackerel and to analyze its ability to produce hydrolase enzymes (amylase, protease, cellulase and lipase).@*Methodology and results@#Ten samples of mackerel were collected from the Fish Auction Place, Lewoleba, Nubatukan District, Lembata Regency, East Nusa Tenggara Province, Indonesia. The process for screening were antimicrobial activity, pH tolerance test of 1, 3 and 5, bile salt concentrations of 2.5%, 5% and 7.5%, and water salinity (0.5%, 3.5% and 6.5%). The autoaggregation and semi-qualitative test of hydrolase enzymes were also carried out. In total, 21 LAB isolates were derived from mackerel intestines. Isolates that have the stronger ability to inhibit the pathogen Aeromonas hydrophila ATCC 7966 are KBP 3.3, KBP 3.3.1 and KBP 6.3, while KBP 1.3, KBP 1.1.1 and KBP 3.3.1 were able to inhibit Streptococcus agalactiae ATCC 13813. The LAB isolates that survived at the tested pH were KBP 3.3.1, KBP 3.3, KBP 1.1.1 and KBP 1.3. Results also suggest that the four isolates were tolerant to bile salt concentrations and water salinity with good survival rates (>94.7%) and had proteolytic, lipolytic and cellulolytic activities. The isolates KBP 3.3, KBP 3.3.1 and KBP 1.1.1 were identified as Weissella confusa 6250, while the isolate KBP 1.3 was identified as W. confusa C5-7.@*Conclusion, significance and impact of study@#The characteristics of four selected isolates indicate their potential as a probiotic. These potential probiotic isolates can be applied directly to fish by utilizing microencapsulation technology or adding to the feed.
Subject(s)
Lactobacillales , Perciformes , IndonesiaABSTRACT
Objective: To examine and study the morphology, epidemiology, and molecular phylogeny of Anisakis larvae in blue mackerel [Scomber australasicus (Cuvier, 1832)] and Indian mackerel [Rastrelliger kanagurta (Cuvier, 1816)] using light microscope, scanning electron microscope, molecular phylogeny, and species delimitation methods for confirmation and investigation of Anisakis species and their evolutionary relationship. Methods: A total of 90 fish (45 per species) were purchased from a department store in Chiang Mai, Thailand. Anisakis samples were investigated for morphological characteristics using light and scanning electron microscopes. Molecular phylogeny and species delimitation methods based on the cox2 gene were performed. Results: The prevalence, mean intensity (Mean±SEM), and mean abundance of Anisakis larvae (Mean±SEM) in blue mackerel were 77.78%, 6.74±1.320, and 5.24±1.107, respectively, and in Indian mackerel, these values were 13.33%, 2.50±0.764, and 0.33±0.159, respectively. Scanning electron microscopy showed the detail of morphological characteristics and provided the different shapes of mucron and excretory pores in Anisakis larvae congruent with the phylogenetic tree. The species tree was congruent with the phylogenetic tree. Conclusions: The prevalence, mean intensity, and mean abundance of Anisakis larvae were higher in blue mackerel. To the best of our knowledge, this is the first time that Anisakis pegreffii was found in blue mackerel in Thailand. The phylogenetic tree also supported the morphological data of Anisakis larvae. However, species delimitation based on cox2 revealed 1-3 possible cryptic species in this genus. Anisakis spp. contamination of fish products is unpleasant and a health concern considering human infection with larvae (anisakiasis) arises.
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Se estimaron valores de la talla de madurez gonadal (L50) de la caballa (Scomber japonicus peruanus) para los años 1994 - 2017 en el litoral peruano. El análisis se realizó para el periodo noviembre - marzo donde ocurre la mayor actividad reproductiva. La proporción de hembras maduras en relación a la talla se ajustó mediante un modelo logístico binomial, para ello se utilizaron modelos lineales generalizados con efectos mixtos (MLGM) que asumieron efectos aleatorios asociados a los periodos. El ajuste con el MLGM, mediante sus efectos fjos estimó una L50 de 24.8 cm de longitud a la horquilla (LH) (24.69 cm - 24.9 cm), mientras que con cambios entre periodos, mediante sus efectos aleatorios, los valores oscilaron entre 20.4 cm y 27.0 cm de LH en promedio. Se observó que un aumento en la temperatura causó la disminución de la L50 en los periodos 1997 - 1999 y 2015 - 2016, los cuales coinciden con la presencia de eventos El Niño. Una correlación positiva fue encontrada entre las L50 y la biomasa desovante, estos cambios en las L50 podrían indicar un efecto de denso-dependencia. No se mostró una tendencia en la serie de L50, por tanto no habría un efecto de la presión de pesca, traducida como la tasa instantánea de mortalidad por pesca (F) sobre la L50. Sin embargo, creemos que estas disminuciones de la L50, en relación a una baja densidad poblacional y principalmente a un incremento en la F deben darse como un efecto a largo plazo y no en eventos puntuales como se reflejaron en nuestros resultados.
The values of size-at-gonad maturity (L50) of chub mackerel (Scomber japonicus peruanus) were estimated for the years 1994 - 2017 in the Peruvian littoral. The analysis was performed for the period November - March where the highest reproductive activity occurs. The proportion of mature females was ftted using a logistic binary model, through generalized linear mixed models (MLGM), which assumes random effects associated with the periods. The GLMM, with fixed effects estimated a L50 of 24.8 cm of fork length (FL) (24.69 cm - 24.9 cm), while with changes between periods, with random effects, L50 ranged between 20.4 cm and 27.0 cm FL. It was observed that an increase in temperature caused the decrease of the L50 in the years 1997 - 1999 and 2015 - 2016, which coincides with El Niño events. A positive correlation was found between the L50 and spawning biomass, so changes in L50 may be a density-dependent effect. There was no trend in the L50 series, so there would be no effect of the fishing mortality (F) on the L50. However, we think that the decrease in the L50 in relation to a low population density and mainly an increase in F should be given as a long-term effect and not in isolated events as our results showed.
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Abstract The aim of this study was to determine the effect of storage temperature on the kinetics of color change of chub mackerel dehydrated in a ternary solution (water, glycerol and salt) and vacuum packaged in films. The color of processed fish can change because of lipids and protein oxidation during storage. Samples were stored at 7, 25 and 35 °C for seven months and kinetic models of 0, 1 and 2 order were applied to describe the color changes. It was observed that an increase in the storage temperature improved the changes in the CIE color values (L*, a* and b*). First-order reaction had the best statistical parameters for a* at the three temperatures tested. The temperature dependence of parameter a* indicated an Arrhenius relationship and the activation energy (Ea) was 44.33 kJ/mol. The parameter b* fitted to the proposed models only in samples stored at 35 °C. The L* value decreased during storage at 25 and 35 °C (pale to dark). Storage at refrigeration temperature (7 °C) minimized the color changes.
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Abstract Growth of Enterobacter aerogenes and accumulation of histamine in chub mackerel (Scomber japonicus) were investigated through measuring bacterial count, histidine decarboxylase (HDC) activity and histamine content in fish samples stored at various temperatures from 4 to 37 °C. Results showed that bacterial count and HDC activity rapidly increased in chub mackerel inoculated with E. aerogenes at storage temperature above 20 °C and reached the highest values (8.64 log CFU/g and 31.68 U/g) at 37 °C. Meanwhile, fish samples stored at 25 and 37 °C for 18 h, formed histamine at above 50 mg/100 g of the potential hazard level. In contrast, bacterial growth and histamine formation were controlled for 36 h by cold storage at low temperature (4 °C). Therefore, strict temperature control was necessary for preservation and processing of chub mackerel in order to assure this marine fish safety.
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For several days, there was a series of mortalities of chub mackerel (Scomber japonicus) that were reared for public exhibition in a private aquarium in Seoul, Korea. As part of the diagnosis of the dead fish, a bacterial isolate from the kidney was cultured, identified, and confirmed to be Vibrio (V.) harveyi using Vitek System 2 and 16S rRNA gene sequencing. Phylogenetic analysis was also performed by the neighbor-joining method. As a result, the V. harveyi isolated from chub mackerels of a private aquarium in Korea, called as SNUVh-LW1, was clustered in the same group with V. harveyi ATCC33843.
Subject(s)
Cyprinidae , Diagnosis , Genes, rRNA , Kidney , Korea , Mortality , Perciformes , Seoul , VibrioABSTRACT
Objective To investigate the mercury exposure level in cord blood of neonatal in Zhoushan Islands and to analyze the related factors,in order to provide scientific basis for relevant prevention and control measures.Methods From June 201 2 to July 201 3,peripheral blood and umbilical cord blood samples were collected in local women who delivered their babies in Zhoushan Islands.Questionnaire survey and mercury exposure test were performed.Results 3 052 maternal blood and neonatal umbilical cord blood samples were tested,and the mean,median,P25 and P75 of the maternal blood mercury were 5.33 ±3.69,4.63,2.8 and 8.2 μg/kg respectively.And the mean,median,P25 and P75 of the cord blood mercury were 7.72 ±4.87,7.31 ,4.7 and 1 1 .2 μg/kg.Single factor analysis showed that the neonatal umbilical cord blood mercury levels were associated the intake of pan -fried mackerel during pregnancy (OR =1 .79,P <0.01 ).No association was found with the sex of newborn,the intake of iron,calcium,and vitamin during pregnancy,the number of mending tooth,the use of whitening cosmetics,the intake of fish and seafood,father's smoking,the average family income and residence time.Multivariate Logistic regression analysis showed that the neonatal umbilical cord blood mercury levels were associated the intake of pan -fried mackerel during pregnancy (OR =1 .96,P <0.01 ).Conclusion Mercury levels in cord blood in Zhoushan area are detected at a high level;the intake of pan -fried mackerel could be one of the major sources of mercury accumulation in neonates.There is an association between the mercury levels of maternal blood and neonatal umbilical cord blood.
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Se analiza información de diversas variables ambientales de macroescala disponibles desde 1876 para el Pacífico Sudoriental y datos más recientes de desembarques y biomasas de jurel Trachurus murphyi Nichols 1920 en el mar peruano en relación con áreas probables de masas de agua equivalentes a Aguas Costeras Frías (ACF) y Aguas Subtropicales Superficiales (ASS). Se concluye que el Índice de Oscilación Decadal del Pacífico (PDO) presenta expresiones de variabilidad coherentes con las encontradas para el Índice de Oscilación del Sur (SOI) y que los cambios observados en las biomasas de T. murphyi en el mar peruano reflejan cambios en la disponibilidad del recurso asociado a patrones de variabilidad seculares (SOI) y decadales (PDO). Tales fluctuaciones en la disponibilidad del recurso afectan las pesquerías de Ecuador, Perú y norte de Chile, las que muestran variaciones importantes en sus desembarques y habrían dado una imagen sesgada de la abundancia conduciendo a diagnósticos errados de la real situación del recurso. Estos patrones de variabilidad afectarían también las manifestaciones de El Niño, haciendo que se inicien en otoños o primaveras australes dependiendo de si el PDO imperante es negativo o positivo. Por otro lado, en función a la distancia euclidiana de las varianzas del SOI se identifican periodos de alta (1876 - 1925 y 1976 - 2012) y baja (1926 - 1975) variabilidad; y con el PDO se diferencian periodos cálidos (1925 - 1944 y 1975 - 1994), frio (1945 - 1974) y templados o interfaces (1895 - 1924 y 1995 - 2012), siendo estos últimos producto de la interacción con los momentos de alta variabilidad
This paper analyses information on various macro environmental variables available since 1876 for the Southeast Pacific and more recent data on Jack mackerel Trachurus murphyi (Nichols, 1920) landings and biomass in the Peruvian sea, relating them to probable areas of water masses equivalent to Cold Coastal Waters (CCW) and Subtropical Surface Waters (SSW). It is concluded that the index of the Pacific Decadal Oscillation (PDO) presents expressions of variability that are consistent with those found for the Southern Oscillation Index (SOI) and that the detected changes in biomass of Jack mackerel T. murphyi in the Peruvian sea reflect changes in the availability of the fish stock associated with secular (SOI) and decadal (PDO) variability patterns. These fluctuations in stock availability impact fisheries in Ecuador, Peru and northern Chile, which show significant variations in their landings and would have given a biased picture of the state of abundance, leading to wrong diagnoses of the real situation of the exploited stocks. These patterns of variability would also affect the appearance of El Niño, making them start in the southern hemisphere autumn or spring depending on whether the current PDO is positive or negative. Periods of high (1876 - 1925 and 1976 - 2012) and low (1926 - 1975) variability are also identified in relation to the Euclidean distance of the variances of the SOI; and in relation to the PDO a distinction is made between warm (1925 - 1944 and 1975 - 1994), cold (1945 - 1974) and tempered or interface periods (1895 - 1924 and 1995 - 2012), the latter being explained by the interaction between periods of high variability
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Se analiza y discute la serie temporal del Índice Gonadosomático (IGS) y la talla de primera madurez del jurel Trachurus murphyi Nichols 1920 en el Perú calculada mensualmente entre los años 1967 - 2012. Sobre la base de estos análisis se determinó la variación anual e interanual del ciclo reproductivo, además se demostró que frente a la costa del Perú T. murphyi tiene un solo periodo de desove relativamente amplio y que ocurre con un máximo en el mes de noviembre de cada año. Asimismo, se evidenció que durante más de cuatro décadas T. murphyi ha desovado regularmente cada año en el mar peruano. La actividad reproductiva del T. murphyi tiene una mayo variabilidad en el Perú y el periodo de desove tiene picos de menor magnitud pero de mayor amplitud con respecto al desove que ocurre frente a la costa de Chile. El análisis de las tallas de primera madurez no presentó cambios significativos a lo largo de toda la serie en el mar peruano.
The time series of monthly gonadosomatic index (GSI) and biannual size at first maturity of Jack mackerel Trachurus murphyi Nichols 1920 in Peru between 1967 and 2012 is analyzed and discussed. The annual and interannual variation of the reproductive cycle was determined. It is shown that in Peru T. murphyi has a single relatively extended spawning period with a maximum in November each year. It is also shown that for more than four decades T. murphyi has spawned regularly every year in Peruvian waters. The reproductive activity of T. murphyi has a greater variability off Peru and the spawning period has peaks of lesser magnitude but extend longer than observed in the spawning occurring off Chile. The analyses of the sizes at first maturity of Jack mackerel in Peruvian waters did not show significant changes throughout the entire period observed.
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El presente trabajo describe la escala de madurez gonadal macroscópica del jurel Trachurus murphyi Nichols 1920, validada con estudios microscópicos y en uso en Perú. La escala consta de seis estadios de maduración para hembras y machos, que van desde el estadio 0 (virginal) al estadio V (recuperación en hembras, posexpulsante en machos). Para el estudio, se contó con 350 ejemplares provenientes del plan de seguimiento de la pesquería pelágica y de cruceros de evaluación de recursos pelágicos; dichos ejemplares fueron colectados desde el 2006 al 2009. La escala cataloga a los individuos virginales en el denominado estadio 0, lo cual permite la separación práctica entre juveniles (estadio 0) y adultos (estadios I a V). Se discute las bondades de la escala validada para el jurel T. murphyi, la cual se compara con otras escalas de madurez propuestas para especies de la misma familia. El análisis de las características microscópicas de los ovarios confirman la tipificación de desove parcial ya descrita por otros autores.
This paper describes the macroscopic scale of gonad maturity stages of Jack mackerel Trachurus murphy Nichols 1920, validated by microscopic studies, and being used in Peru,. A scale of six maturity stages are identified for females and males, ranging from stage 0 (virgin) to stage V (recovery in females, post-spermiation in males). The gonads of 350 specimens were analyzed. These specimens were collected as part of a pelagic fishery monitoring programme and during pelagic stock assessment surveys between 2006 and 2009. Virgin individuals are classified as stage 0 (virgin), which draws the distinction between (non-reproductive) juveniles and (reproductive) adults in stages I to V. The advantages of using the validated stages of gonad development of Jack mackerel T. murphyi are discussed and are compared to other scales of maturity stages proposed for other species in the same family. The analysis of the microscopic characteristics of the ovaries confirms that Jack mackerel is a batch spawner, which has already been described by other authors.
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Se determinó la edad y se estimó el crecimiento del jurel Trachurus murphyi Nichols 1920, mediante la lectura y medición de anillos anuales de crecimiento en 977 pares de otolitos de especímenes entre 3 y 71 cm de longitud total colectados dentro del dominio marítimo peruano durante el año 1978 y parte de 1977 y 1979. Se comprobó la validez de las marcas anuales en 50 otolitos con 5 marcas o zonas anuales, y también con el análisis del incremento marginal mensual en 240 otolitos de especímenes entre 35 y 39 cm obtenidos entre julio 1977 y junio 1979. A partir de las medidas de los anillos anuales y sus respectivas tallas retrocalculadas se estimaron los parámetros de crecimiento en longitud y peso de la ecuación de von Bertalanffy: longitud infinita (L∞) =80.77 cm, peso infinito (W∞) = 3744.10 g, coeficiente de crecimiento (k) = 0.155 y edad teórica a la longitud 0 (t0) = -0.356. Se discuten las diferencias y semejanzas con las curvas y parámetros de crecimiento calculados por otros autores, haciendo énfasis en aquéllos cuyos resultados contribuyen a validar los estimados en el presente trabajo. Según los parámetros estimados, el T. murphyi peruano tendría una velocidad de crecimiento mayor que el T. murphyi de más al sur
The age and growth of Jack mackerel Trachurus murphyi Nichols 1920 was determined by the reading and measuring annual growth rings from 977 pairs of otoliths from specimens between 3 and 71 cm total length collected within the Peruvian maritime domain during 1978 and part of 1977 and 1979. The validity of the annual marks was confirmed with 50 otolith with 5 marks or annual zones, and also with the analysis of the monthly marginal increment in 240 otoliths of specimens between 35 and 39 cm obtained from July 1977 to June 1979. From the annual rings measurements and their respective retroestimated sizes, the following parameters of the von Bertalanfy ecuation for growth in length and weight were estimated: infinite length (L∞) = 80.77 cm, infinite weight (W∞) = 3744.10 g, growth coefficient (k) = 0.155, and theoretical age at length 0 (t0) = -0.356. The estimated parameters suggest that the Peruvian T. murphyi has a faster growth rate than the more southern T. murphyi
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Se presentan las estimaciones de los parámetros de crecimiento del modelo de von Bertalanffy para el jurel Trachurus murphyi Nichols 1920 capturado en el mar peruano entre 1972 y 2012, a partir de análisis de frecuencias por tallas. La L∞ fue estimada a partir de la máxima talla observada a lo largo de la historia de su pesquería y se le mantuvo como parámetro fijo en la estimación del parámetro de crecimiento k a partir del ajuste directo de una curva de crecimiento sobre la progresión mensual de modas. Los valores estimados fueron: L∞ = 81.6 cm y k = 0.167 año-1. Se destaca que este valor de k es similar al estimado por otros autores y con otros métodos para el Perú, y es a su vez más alto que el estimado para el T. murphyi capturado frente a las costas de Chile. Estos resultados sugieren que el T. murphyi en el Perú tiene una velocidad de crecimiento más alta que el T. murphyi de Chile
This paper presents estimates of the von Bertalanffy growth parameters for Jack mackerel T. murphyi caught in Peruvian waters from 1972 to 2012, based on length frequency analysis. L∞ was estimated from the maximum length observed throughout the history of the fishery, and was kept as a fixed parameter in the estimation of k obtained by fitting a growth curve to the monthly progression of modes. The estimated values were: L∞ = 81.6 cm and k = 0.167y-1. It is highlighted that this k values is similar to those estimated by other authors for Peru, and is higher than those estimated for the T. murphyi caught off in Chile. These results suggest that T. murphyi caught in Peru has a faster growth rate than the T. murphyi from Chile
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Se analiza información de cruceros bio-oceanográficos del IMARPE con estaciones hasta 100 mn de la costa y entre 0 y 180 m de profundidad entre 1961 y 2011; información de observadores científicos a bordo de buques arrastrero-factoría de media agua nacionales, soviéticos y cubanos que operaron entre 1983 y 1998; y series de tiempo de anomalías de temperatura superficial del mar, profundidad de la isoterma de 15 °C y salinidad de 1950 a la fecha. Se identifican y describen tres patrones de distribución vertical y profundidad de las capturas de jurel Trachurus murphyi en relación a cambios en condiciones ambientales: (1) cuando ocurren fenómenos El Niño (EN) fuertes los cardúmenes se distribuyen entre 100 y 200 m de profundidad, las capturas son altas y varían poco entre día y noche; (2) cuando hay fuertes afloramientos los cardúmenes se distribuyen entre 0 y 75 m de profundidad, la pesca es más oceánica y superficial y (3) cuando se refuerza la Extensión Sur de la Corriente de Cromwell (ESCC), los cardúmenes están entre 0 y 300 m de profundidad, la pesca es más costera, a mayor profundidad de día y más superficial de noche. T. murphyi es menos abundante en períodos fríos, cuando dominan Aguas Costeras Frías (ACF) y se alejan de la costa las Aguas Subtropicales Superficiales (ASS), y más abundante en periodos cálidos, asociados a eventos EN y dominancia de la ESCC. Se observa segregación latitudinal por tamaños en relación a la Oscilación Decadal del Pacífico
This paper analyzes information from IMARPE bio-oceanographic surveys conducted between 1961 and 2011 covering an area from 0 to 100 nm from the coast with observations at depths from 0 to 180 m; information from scientific observers on board Peruvian, Soviet and Cuban factory trawlers operating between 1983 - 1998; as well as time series of sea surface temperature anomalies, depth of the 15 °C isotherm and sea surface salinity from 1950 to date. Three patterns in the vertical distribution and depth of catches of Jack mackerel Trachurus murphyi are identified and described in relation to changing environmental conditions: (1) During strong El Niño (EN) events shoals are at depths between 100 - 200 m, catches are higher and dont change much between day and night; (2) During strong upwellings shoals are shallower, at depths between 0 - 75 m and catches are more oceanic (offshore) and closer to the surface; and, (3) When there is a strengthen Southern Extension of the Cromwell Current (SECC) shoals are at depths between 0 and 300 m, fishing takes place closer to the coast being deeper during the day and shallower during the night. During cold periods there is lower abundance of T. murphyi due to the prevalence of Cold Coastal Waters (CCW) and the offshore shift of the Subtropical Surface Waters (SSW), while abundance is higher during warmer periods associated with EN events and the strengthening of the SECC. A certain latitudinal segregation by sizes in relation to the Pacific Decadal Oscillation is also observed
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Se analizó la variabilidad espacio-temporal de la dieta de jurel Trachurus murphyi frente a Perú de 1977 a 2011. Un total de 21058 estómagos fueron analizados utilizando métodos bivariados y el Modelo de Árbol de Regresión Multivariado (ARM). Se utilizó como variable respuesta la composición gravimétrica de la dieta, con respecto a diferentes variables pre dictivas como años, profundidad de la isoterma de 15 °C, Índice de Oscilación del Sur (IOS), Índice de Oscilación Decadal del Pacífico (PDO), anomalía de la temperatura superficial del mar, zona (norte, centro y sur) y distancia de la costa. Nuestros resultados nos permitieron identificar dos escenarios diferentes, uno desde el año 1977 al 2000, donde la dieta del jurel T. murphyi estuvo fuertemente dominada por Euphausiidae, y otro escenario después del 2000, donde el jurel T. murphyi consumió mayor diversidad de presas, principalmente Euphausiidae, camaroncito rojo Pleuroncodes monodon y Zoeas. Se destaca que el primer escenario corresponde a condiciones cálidas y el segundo a condiciones frías, ambas coincidentes con los periodos multidecadales. A diferencia de estudios anteriores que muestran que la anchoveta Engraulis ringens es una presa abundante, en este estudio no fue significativamente importante. Espacialmente, los Euphausiidae dominaron la dieta en el norte-centro de Perú, mientras que al sur, la composición de las presas fue más diversa. La dieta también varió significativamente según la distancia a la costa, con mayor proporción de P. monodon cerca a la costa y con respecto a su etapas de desarrollo ontogenético.
We analyzed the spatiotemporal variability of Jack mackerel Trachurus murphyi diet off Peru from 1977 to 2011. A total of 21058 stomachs were analyzed using bivariate methods and the Multivariate Regression Tree Model (MRT). The gravimetric composition of the diet was used as response variable with respect to different predictor variables such as years, depth of the 15°C isotherm, Southern Oscillation Index (SOI), Index of the Pacific Decadal Oscillation (PDO), sea surface temperature anomaly, zone (north, center and south) and distance to the coast. Our results allowed us to identify two different scenarios. From 1977 to 2000 the Jack mackerel T. murphy diet was strongly dominated by Euphausiidae, and since 2000 when T. murphyi consumed a greater diversity of prey, mainly Euphausiidae, squat lobster Pleuroncodes monodon and Zoea. It is noted that the first scenario corresponds to warm conditions and the second to cold conditions, both coincident with observed multidecadal periods. In contrast to previous studies showing that the anchovy Engraulis ringens is an abundant prey, in this study anchovy was not significantly important. Spatially, the Euphausiidae dominated the diet in central-northern Peru, while further south the prey composition was more diverse. The diet also varied significantly according to the distance from the coast (higher proportion of P. monodon closer to the coast) and the ontogenic stages.
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El análisis espacial y temporal de larvas de jurel Trachurus murphyi en el mar peruano entre los años 1966 y 2010 confirma su presencia constante durante todo el periodo estudiado. En general, en este periodo la abundancia de larvas de jurel T. murphyi muestra una tendencia ligeramente ascendente destacándose cambios en la distribución espacial y una alta variabilidad interanual, con cortos periodos de alta abundancia promedio, intercalados con periodos más prolongados y de baja abundancia. El promedio anual estimado varió entre 3 y 79 larvas/m². La distribución espacial presentó tres periodos importantes: uno con mayores densidades de larvas al sur de los 14°S, entre 1970 y 1979; cambió hacia el norte de esta latitud, entre 1980 y 1999; y otro de mayor densidad al sur de los 18°S, en el último periodo 2000 - 2010. Los centros de gravedad de la distribución de larvas presentaron tres periodos muy notorios: fueron más costeros hacia el sur de los 14°S, entre 1966 y1978; más oceánicos y al norte de los 14°S, entre 1979 y 1994; y con una posición intermedia entre 1995 - 2010. Se discute la relación entre la distribución de las larvas con las variables oceanográficas y la distribución de T. murphyi adultos y juveniles, además se destaca que el mar del Perú es un centro principal y permanente de actividad reproductiva de esta especie.
Constant presence of Jack mackerel Trachurus murphyi larvae in the Peruvian sea between 1966 and 2010 was confirmed by an analysis of their spatial and temporal variability. In general, there is a slight positive trend in abundance of Jack mackerel T. murphyi larvae, with noticeable changes in their spatial distribution and high interannual variability. High abundance of larvae is observed in some years, which are usually followed by a longer sequence of poor abundance years. Yearly averages varied between 3 and 79 larvae/m². The spatial distribution of average larvae density showed three notorious periods along time: the first between 1970 and 1979 with higher larvae densities south of 14°S; the second between 1980 and 1999 with the higher densities to the north of 14°S; and the third between 2000 and 2010 with higher densities south of 18°S. The displacement of the centers of gravity of the spatial distribution marked three noticeable periods: between 1966 and 1978 were more coastal, south of 14°S; between 1979 and 1994 more oceanic and north of 14°S; and between 1995 and 2010 which were at an intermediate position. The relationship of larvae density with oceanographic variables as well as with the distribution of adult and juvenile Jack mackerel T. murphyi are discussed, stressing the observation that there is a main center of permanent spawning activity of this species in Peruvian waters.
ABSTRACT
Se analizan los resultados de las evaluaciones hidroacústicas del recurso jurel Trachurus murphyi Nichols 1920 realizadas en aguas peruanas entre 1983 - 2012. Desde 1983 se incluyó al T. murphyi como especie de estudio durante los cruceros de evaluación de recursos pelágicos ejecutados por el Instituto del Mar del Perú. Debido al énfasis en la estimación de biomasa de la anchoveta Engraulis ringens y de la sardina Sardinops sagax cuando esta última es más abundante, los cruceros se llevan a cabo durante el verano austral y las áreas de evaluación están circunscritas a las zonas más costeras hasta 100 mn, con sólo algunas exploraciones en otras estaciones y hasta 200 millas. El máximo valor de biomasa de 8.51 millones de toneladas de T. murphyi en aguas peruanas estimado con las evaluaciones hidroacústicas fue encontrado durante el crucero realizado en otoño (marzo-mayo) de 1983. En los años siguientes los estimados de biomasa acústica fluctuaron entre 180 mil toneladas en 1985 y otro máximo de 8.47 millones de toneladas en 1993, para luego disminuir gradualmente hasta un mínimo de 1239 t en 2010, con una ligera recuperación en los años 2011 y 2012. El área de distribución de T. murphyi fue muy fluctuante en todo el periodo observado.
This paper analyzes the results of acoustic stock assessment surveys for Jack mackerel Trachurus murphy Nichols 1920 conducted in Peruvian waters between 1983 and 2012. Since 1983 Jack mackerel T. murphyi was included as a target species to be assessed during the pelagic stock assessment surveys executed by the Peruvian Institute of Marine Research. Due to the emphasis on the assessment of anchovy Engraulis ringens and sardine Sardinops sagax when this species was abundant, these surveys usually took place during the austral summer and only covered the first 100 nautical miles from the coast, and only occasional surveys were conducted in other seasons or surveyed as far as 200 nm offshore. A maximum biomass of 8.51 million t of T. murphyi in Peruvian waters estimated through acoustics during a survey carried out in autumn (March-May) 1983. In the following years acoustic biomass estimates ranged between 180 thousand t in 1985 and another maximum of 8.47 million t in 1993, to then decreased gradually to a minimum of 1239 t in 2010, with a slight recovery in 2011 and 2012. The areas of distribution of T. murphyi have been fluctuating markedly throughout the observed period.
ABSTRACT
La presencia del jurel Trachurus murphyi ha sido registrado en los desembarques de la pesca artesanal en Perú desde 1907. A partir del año 2000, las capturas de T. murphyi se ubicaron en el tercer lugar después de la anchoveta Engraulis ringens y el calamar gigante Dosidicus gigas. Las capturas de T. murphyi son realizadas por la flota artesanal, industrial cerquera y barcos arrastreros factoría. En el año 2011, la flota industrial cerquera con permiso de pesca para T. murphyi en la costa peruana estaba constituida por 62 embarcaciones industriales de acero (30177 m³) y 42 industriales de madera (3082 m³). Las capturas de T. murphyi tuvieron un notable incremento a partir de 1972, alcanzando sus máximos valores en 1977, 1996-97 y 2001, a los que siguieron años de muy baja disponibilidad que llevó al mínimo registro en las capturas en 2010. Sin embargo en el 2011 se revirtió esta baja disponibilidad y las capturas alcanzaron casi las 260000 toneladas. En el periodo 1972 - 2012 se observó una relación inversa entre los estimados de biomasa acústica del jurel T. murphyi y los desembarques anuales de anchoveta E. ringens. Las capturas mensuales de T. murphyi por la flota industrial y artesanal antes del 2002 fueron altas en la zona norte de Perú (Mancora-Chimbote), mientras que después del 2002 las capturas fueron altas en la zona centro-sur (Huacho-Ilo).
There are records of the presence of Jack mackerel Trachurus murphyi in the artisanal fishery landings in Peru since 1907. Since 2000 Jack mackerel T. murphyi catches are ranked third after anchovy Engraulis ringens and jumbo squid Dosidicus gigas. Artisanal, industrial purse seine and offshore (factory trawlers) fleets take part in the Peruvian catches of T. murphyi. In 2011 the industrial purse-seine fleet with license to fish for T. murphyi along the Peruvian coast comprised of 62 industrial steel vessels (30177 m³) and 42 industrial wood vessels (3082 m³). Catches of T. murphyi had a significant increase after 1972, with maximum catches in 1977, 1996-97 and 2001, after which several years of low availability followed, with the lowest catches in 2010. However, this low availability trend was reversed in 2011, and catches reached almost 260 thousand tons that year. A general inverse relationship has been observed between the T. murphyi estimated acoustic biomass and the annual landings of anchovy E. ringens during the the period 1972 - 2012. The monthly catches of T. murphyi by the industrial and artisanal fleets before 2002 were higher in the northern part of Peru (Mancora-Chimbote) while after 2002 the catches were higher in the south-central zone (Huacho-Ilo).
ABSTRACT
Las pesquerías peruanas como actividades realizadas sobre recursos naturales renovables son reguladas por un marco jurídico, cuyo objetivo es asegurar su conservación y uso sostenible. La Ley General de Pesca (DL N°. 25977) señala que para cada tipo de pesquería y según la situación del recurso explotado debe establecerse un sistema de ordenamiento que concilie el principio de sostenibilidad de los recursos pesqueros o conservación en el largo plazo, con la obtención de los mayores beneficios económicos y sociales. En el ordenamiento pesquero del jurel Trachurus murphyi, las medidas incluyen entre otras, el régimen de acceso constituido por las autorizaciones de incremento de flota y permisos de pesca, que se otorgan solo a los buques cuyas capturas son destinadas únicamente para el consumo humano directo, de acuerdo a lo dispuesto en el Reglamento de Ordenamiento Pesquero (DS N.° 011-2007-PRODUCE). La obligación de destinar los recursos sardina Sardinops sagax, jurel T. murphyi y caballa Scomber japonicus al consumo humano directo rige desde septiembre 2002 (DS N°. 001-2002-PRODUCE). Otras medidas vigentes restringen el tamaño mínimo de malla de las redes, prohíben la captura de ejemplares menores de 31 cm de longitud total, determinan el inicio y cierre de las temporadas de pesca, los límites de captura o cuotas anuales. Estas disposiciones son complementadas por medidas de seguimiento, control y vigilancia para la efectiva conservación y uso sostenido del recurso.
The Peruvian fisheries exploit renewable natural resources and as such are regulated by a legal framework aiming at ensuring their conservation and sustainable use. The General Fisheries Act, DL N°. 25977, points out that fisheries management systems shall be established for each type of fishery taking into account to the state of exploitation of the fishery resources, reconciling the principles of sustainability and long-term conservation with those aiming at the attainment of the maximum possible economic and social benefits. According to the provisions of the Fisheries Management Regulations approved by SD N°. 011-2007-PRODUCE, the management of the Jack mackerel Trachurus murphyi fisheries includes among others, a fishing access regime that regulates the fleet size and the allocation of fishing licenses, which can only be granted to vessels fishing only for direct human consumption. The obligation to allocate the resources sardine Sardinops sagax, Jack mackerel T. murphyi, and mackerel Scomber japonicus, for direct human consumption has been in force since September 2002, following the ruling established by SD N°. 001-2002-PRODUCE. Other measures currently in force include those establish a minimum mesh size, the ban to catch or land specimens under 31 cm total length limit, the opening and closing of the fishing seasons, and catch limits or annual quotas. These provisions are supplemented by measures for monitoring, control and surveillance, and for the effective conservation and sustainable use of the fishery resources.
ABSTRACT
The Serra Spanish mackerel, Scomberomorus brasiliensis is an important fishery resource of the Atlantic Ocean and is a major component of artisanal fisheries in northern and northeastern Brazil. Ovarian development and spawning period of S. brasiliensis were investigated using both macroscopic and histological techniques. Mean monthly values of GSI and ovarian maturation indicate that the main spawning period occurs during the rainy season.
A Serra, Scomberomorus brasiliensis, é uma espécie marinha de valor comercial do oceano Atlântico sendo um maior componente de pesca artesanal no norte e nordeste brasileiros. Desenvolvimento ovariano e época de desova de S. brasiliensis foram investigados utilizando-se técnicas macroscópicas e histológicas. Valores mensais médios de IGS e maturação gonadal indicam que a época de desova ocorre durante o período de chuva.