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We attempted to estimate the survival rates of larval cohorts (3–15 mm in body length) of the Japanese anchovy Engraulis japonicus population in Hiuchi-nada, Seto Inland Sea, Japan, and examined the relationship to their food availability. The survival rates were directly calculated from the change in larval density during the survey. The estimated daily survival rate ranged between 0 and 89% d−1, but increased with the increase in the mean concentration of small-sized copepod nauplii (<100 μm in body length) sampled at 10 m depth. When the food concentration was higher than about 5 nauplii L−1, the daily survival rate of larval anchovy reached an asymptote of approximately 89% day−1. It might be possible to provide a framework for the forecast for larval abundance immediately prior to recruitment size (10–15 mm SL), based on larval abundance of the monitored size (3–8 mm SL) and the survival rate which is estimated from the concentration of small-sized nauplii. [ABSTRACT FROM AUTHOR] more...

Abstract: In the Bay of Biscay, anchovy juveniles are regularly observed off the shelf whereas spawning occurs over the shelf, mainly in the river plumes. This distribution of the juveniles can be interpreted as advective losses of the population recruiting over the shelf. However, recent research suggests an alternative interpretation based on the possibility of the population exploiting the off the shelf waters for recruitment through a loophole of lower predation. In this article, we test this second hypothesis through a review of the information available about different processes in the Bay of Biscay (anchovy distribution, size at age spatial differences, recruitment timing and spatial distribution and potential predators distribution). We also develop a model to explore recruitment success when predation risk is positively correlated with feeding opportunities. We conclude that the hypothesis of anchovy using off-shore (oceanic) waters as a spatial loophole for recruitment cannot be excluded. [Copyright &y& Elsevier] more...

The spatio-temporal distribution of the anchovy Engraulis encrasicolus in its early life stages was related to environmental conditions within the Guadalquivir River estuary (south-west, Spain) by monthly field surveys during nine periods of recruitment (May 1997 to December 2005). Anchovy post-larvae showed a consistent seasonal pattern of abundance throughout the study period: each year, a high anchovy recruitment period (HARP) occurred from late May to November, with a main peak in July, coinciding with the period when environmental conditions were more stable. Results of stepwise multiple regression analysis indicates that density of its main prey, Mesopodopsis slabberi, explained 45% of total anchovy density variance. Furthermore, after removing the effect of this variable, interannual differences in the anchovy estuarine recruitment were not significant. Clear spatial and tidal trends were also observed for both prey and predator: at each sampling date, density decreased from the outer to inner estuary; at each sampling site, density was higher during ebbs than during floods. Field distributions related to environmental gradients during HARP indicated that the populations of E. encrasicolus and M. slabberi seemed to hold a steady position at a point on the salinity gradient by longitudinal displacement within the estuary. Since freshwater management actions affect the longitudinal position of the salinity gradient as well as the input of nutrients to the estuary and adjacent coastal areas, it is hypothesized that this factor may also be relevant to anchovy recruitment. [ABSTRACT FROM AUTHOR] more...

The distribution of egg and larvae of mackerel, horse mackerel, sardine, hake, megrim, blue whiting and anchovy along the European Atlantic waters (south Portugal to Scotland) during 1998 is described. Time of the year, sea surface temperature and bottom depth are used to define the spawning habitat of the different species. Mackerel, horse mackerel, and sardine eggs and larvae presented the widest distribution, whereas megrim and anchovy showed a limited distribution, restricted to the Celtic Sea and the Bay of Biscay respectively. Correspondingly mackerel, horse mackerel and sardine showed the highest aggregation indices. Blue whiting larvae were found at the lowest temperatures, whereas anchovy eggs and larvae were found in the warmest waters. The analysis is a basis for evaluation of ongoing changes in the pelagic ecosystem of the north-east Atlantic. [ABSTRACT FROM AUTHOR] more...

Plagányi, É. E., Rademeyer, R. A., Butterworth, D. S., Cunningham, C. L., and Johnston, S. J. 2007. Making management procedures operational — innovations implemented in South Africa. – ICES Journal of Marine Science, 64: 626–632.Operational management procedures (OMPs) have become an indispensable fisheries management tool in South Africa in light of their ability to consider the consequences of the main sources of assessment uncertainty. An overview is provided of the MP approaches applied to the major South African fisheries for hake, sardine and anchovy, and west coast rock lobster. As these are among the first OMPs to be implemented worldwide, some for periods longer than 10 y, they provide useful examples of some of the successes and problems encountered with the approach. Particular emphasis is given to some recent innovations and adaptations. These include moves to (i) joint two-species OMPs for the hake and sardine/anchovy resources; (ii) a reference set of weighted operating models for primary testing and tuning in preference to a single model; (iii) consideration of a “research-conditional” approach for hake to allow greater catches in the short term, conditional on research being implemented to resolve a key uncertainty; and (iv) incorporation of some ecosystem considerations by developing appropriate robustness tests (which link with moves towards an ecosystem approach to fisheries). Key lessons gained from experience over the past decade of OMP implementation in South Africa are summarized. [ABSTRACT FROM PUBLISHER] more...

De Lara, M., Doyen, L., Guilbaud, Th., and Rochet, M-J. 2007. Is a management framework based on spawning-stock biomass indicators sustainable? A viability approach. – ICES Journal of Marine Science, 64: 761–767: 000–000. Fisheries management agencies have to drive resources on sustainable paths, i.e. within defined boundaries for an indefinite time. The viable-control approach is proposed as a relevant method to deal with sustainability. We analyse the ICES precautionary approach (PA) by means of the notion of viability domain, and provide a mathematical test for sustainability. It is found that the PA based on spawning-stock biomass (SSB) and fishing mortality (F) indicators is sustainable only when recruits make a significant contribution to SSB. In this case, advice based upon SSB, with an appropriate reference point, is sufficient to ensure sustainability. In all other cases, SSB is not a sufficient metric of stock productivity and must be complemented with other management indicators to ensure sustainability. The approach is illustrated with numerical applications to the northern hake and Bay of Biscay anchovy. [ABSTRACT FROM PUBLISHER] more...

Through most of the last century, three endemic kilka species supported major commercial species in the Caspian Sea. It is clear that catches and abundance of all species have changed, but catch and sampling data are limited and stock assessments are inadequate. Recent changes in the Caspian Sea ecosystem have occurred as a consequence of climatic environmental change (sea level change) and ecologic change caused by the invasive ctenophore Mnemiopsis leidyi. This paper examines the effects of these changes on the population biology and biomass of anchovy kilka Clupeonella engrauliformis in Iranian waters of the Caspian Sea from 1995 to 2004. For most years during this 10-year period, we estimated the age structure of catch, length–weight relationship, von Bertalanffy growth parameters, condition factors, sex ratios, maturity stages determined from ovarian analysis, natural and fishing mortality, age at first capture, and spawning biomass. The instantaneous coefficient of natural mortality was estimated as 0.473/year and the instantaneous coefficient of fishing mortality varied during the 10-year period between 0.541 and 2.690/year. Biomass of anchovy kilka declined from about 186 000 t in 1996 to less than 12 000 t in 2004. Recent high fishing rates were not sustainable after the introduction of Mnemiopsis, so overfishing is part of the explanation for the collapse of anchovy kilka in the Caspian Sea. [ABSTRACT FROM AUTHOR] more...

Based on Santojanni et al. [Santojanni, A., Arneri, E., Barry, C., Belardinelli, A., Cingolani, N., Giannetti, G., Kirkwood, G., 2003. Trends of anchovy (Engraulis encrasicolus, L.) biomass in the northern and central Adriatic Sea. Sci. Mar. 67(3), 327–340] stock size estimates for the period from 1975 to 1996, we constructed a model to investigate population dynamics of anchovies. Using numeric simulations we calculate the maximum sustainable catch (MSC) as well as the optimum level of spawning stock to maintain the MSC. By comparing computed levels with Santojanni et al. estimates, we find that the anchovy population is below the optimum level, i.e. overfished since 1982. We find evidence of overfishing in 1982, 1985, 1986 and 1988. We claim the large catch in 1985 was more responsible for the collapse of anchovy fisheries in 1987 than low recruitment levels. We investigate possible ways of fishing using the two stage model by considering three fishing scenarios: the whole stock is fished with equal effort, only mature individuals are fished, mature and immature individuals are fished with unequal effort. We show that the best strategy is to fish only the spawning stock. [Copyright &y& Elsevier] more...

The Gulf of Lions is one of the main anchovy ( Engraulis encrasicolus) spawning areas in the NW Mediterranean. During the spring, low-salinity surface water from the outflow of the Rhône is advected by the shelf-slope current along the continental slope off the Catalan coast. In June 2000, a Lagrangian experiment tracking these low-salinity surface waters was conducted to assess the importance of this transport mechanism for anchovy larvae and to determine the suitability of the tracked surface waters for survival of anchovy larvae. The experiment consisted of sampling the tracked water parcel for 10 days with three drifters launched at the core of the shelf-slope current where low-salinity surface waters were detected. The survey was completed by sampling the surrounding waters. Anchovy larvae from the spawning area in the Gulf of Lions were advected towards the south in the low-salinity waters. The size increase of anchovy larvae throughout the Lagrangian tracking closely followed the general growth rate calculated by otolith analysis (0.65 mm day−1). However, advection by the current was not the only mechanism of anchovy larval transport. A series of anticyclonic eddies, originated in the Gulf of Lions and advected southwards, seemed to play a complementary role in the transport of larvae from the spawning ground towards the nursery areas. These eddies not only contributed to larval transport but also prevented their dispersion. These transport and aggregation mechanisms may be important for anchovy populations along the Catalan coast and require further study. [ABSTRACT FROM AUTHOR] more...

A study of common minke and Bryde's whales was conducted in the western North Pacific in the 2000 and 2001 summer seasons to estimate prey selection of cetaceans as this is an important parameter in ecosystem models. Whale sighting and sampling surveys and prey surveys using quantitative echosounder and mid-water trawl were carried out concurrently in the study. Biomasses of Japanese anchovy, walleye pollock and krill, which were major prey species of common minke and Bryde's whales, were estimated using an echosounder. The results suggested that common minke whale showed prey selection for Japanese anchovy while they seemed to avoid krill in both the offshore and coastal regions and walleye pollock in the continental shelf region. Selection for shoaling pelagic fish was similar to that in the eastern North Atlantic. Bryde's whale showed selection for Japanese anchovy in August 2000 and July 2001, while it showed prey selection for krill in May and June in 2001. [ABSTRACT FROM AUTHOR] more...

The ability to discriminate local stocks of Japanese anchovy Engraulis japonicus was assessed based on data from four elements (K, Na, P, and Sr) using an electron probe micro analyzer (EPMA) and data from three elements (Ba, Mn, and Sr) using inductively coupled plasma mass spectrometry (ICP-MS) from the otoliths of 40 anchovy (23.6–47.0 mm body length). Anchovy were caught at three sites (Aki-nada, Hiuchi-nada, and Osaka Bay) in the Seto Inland Sea, and one site (Kuroshio extension) in the Pacific Ocean in 2002. In order to discriminate different spawning grounds, EPMA data from the core portion (from core to 30 μm in the core-posterior axis) were used. Results showed that it was difficult to discriminate between the Seto Inland Sea and the Pacific anchovy by EPMA data. Conversely, it was possible to discriminate between the Seto Inland Sea and the Pacific anchovy by ICP-MS data from bulk otoliths. Our results showed that Mn contents of otoliths using ICP-MS discriminate between spawning grounds most, and Ba and Sr discriminate less. The difference in elemental compositions in anchovy otoliths between the Seto Inland Sea and the Pacific Ocean might be reflected by cumulative experienced elemental composition of ambient sea water during life history between the Seto Inland Sea and the Pacific anchovy. [ABSTRACT FROM AUTHOR] more...

Abstract: Cannibalism by Engraulis anchoita on their eggs was investigated on the spring spawning ground of the northern population of the species during the 1993–1999 period. Egg distribution was patchy and egg cannibalism was only found in a limited number of fish. The maximum number of eggs found in a single stomach analyzed was 433. This value corresponded to 5.1% of the total number of eggs in the stomach of all fish sampled in 1993. Mean number of anchovy eggs per stomach ranged between 3.9 and 10.0 (mean S.E.: 1.5–5.1) for 1993–1996 and 1.3 (mean S.E.: 0.5) for 1999. Consumption of eggs over a 12-h feeding period represented, on average, 15–33% (mean S.E.: 6.2–20.1) of the total egg mortality within the study area in 1993–1996, but only 2% (mean S.E.: 0.8) in 1999. The mean abundance of copepods in the plankton samples (69,000copepods/m2), especially calanoids, in 1999 was higher than in previous years (6000–53,000copepods/m2). The same pattern was observed with the number of copepods ingested (400 copepods by fish in the 1993–1996 period and 1200 in 1999). Relationship between consumption rate and density of plankton eggs revealed a marked decrease in the egg cannibalism to low egg density values and an increase of that parameter with the increment of the plankton eggs. There was strong evidence of a decrease in egg cannibalism as copepod density increased. Our results indicate that not only intra-specific predation on anchovy eggs was high, but also anchovy egg cannibalism could be an extra source of energy when the principal food (calanoid copepods) is scarce. In areas where cannibalism was intense, that behavior supplied 91% of the daily energy necessary for reproduction. [Copyright &y& Elsevier] more...

Anchovy and common sardine co-occur in the same reproductive and feeding habitat off central southern Chile (33?00''?41?20''S), and have a similar reproductive strategy. Egg-survey data from one survey carried out during the austral winter in 2005 were used to analyze the spawning spatial structure of anchovy (Engraulis ringens) and common sardine (Strangomera bentincki) through geostatistical techniques and generalized additive models. The spawning spatial structure of both species was characterized by a spatial autocorrelation intensity varying similarly with distance in all directions, ranging between 27.2 and 32.6?km for anchovy and common sardine, respectively. In average, egg density of anchovy was higher than egg density of common sardine, with the bulk of the spawning for both species located in the southern sector of the study area (38?S?40?S). In this sector, both species showed an overlapped distribution, and egg densities were mainly associated to shallow and coastal zones, suggesting that coastal shape and bottom depth are important factors for the spawning of both species. In the south sector, the egg density of both species was positively correlated, indicating that spatial structure of the spawning is not explained by a different strategy of space occupation among anchovy and common sardine. L''anchois et la sardine commune fr?quentent les m?mes zones de reproduction et d''alimentation au large du Chile (Centre-Sud, 33?00''?41?20''S), et ont des strat?gies similaires de reproduction. Les donn?es d''une campagne oc?anographique de r?coltes des oeufs, qui s''est d?roul?e durant l''hiver austral de 2005, ont ?t? utilis?es pour analyser la structure spatiale des pontes de l''anchois (Engraulis ringens) et de la sardine (Strangomera bentincki), au moyen de techniques g?ostatistiques et de mod?les additifs g?n?ralis?s. La structure spatiale des deux esp?ces ?tait caract?ris?e par une intensit? d''autocorr?lation spatiale variant avec la distance et de fa?on similaire dans toutes les directions, s''?tendant de 27,2 ? 32,6?km respectivement, pour l''anchois et la sardine. En moyenne, la densit? en ?ufs d''anchois ?tait plus ?lev?e que celle de la sardine, avec une zone de forte densit? pour les deux esp?ces, situ?e dans le secteur sud de la zone d''?tude (38?S?40?S). Dans ce secteur, les distributions des deux esp?ces se recouvraient, et les densit?s en oeufs ?taient associ?es principalement ? des zones c?ti?res et peu profondes, sugg?rant que la forme de la c?te et la profondeur sont des facteurs importants pour la reproduction des deux esp?ces. Dans le secteur sud, la densit? en ?ufs des deux esp?ces ?tait positivement corr?l?e, indiquant que la structure spatiale des pontes n''est pas expliqu?e par une strat?gie diff?rente de l''occupation de l''espace entre l''anchois et la sardine. [ABSTRACT FROM AUTHOR] more...

Interdecadal versus interannual time-scale variations of catch data of three anchovy fisheries distributed in the Humboldt Current System (HCS) were analyzed during the period 1960?2002, by using first a loess smoother. The?loess residual data were considered as the interannual variation. Interdecadal changes were highly coherent for the three fisheries of anchovy distributed in the HCS, while there were differences in terms of interannual variations. The north-central Peru fishery was similar to the south Peru-northern Chile fishery in terms of the interannual component of fluctuation of these fisheries which was significantly and negatively related with El Ni?o-Southern Oscillations events occurring during the spring of the previous year. Interdecadal synchronous variations in the three anchovy fisheries suggest a common forcing by long-term environmental factors in the HCS, although other causes cannot be excluded. During the last 40 years, coherent changes in anchovy fisheries were observed, and this synchronous pattern is out of phase with large-amplitude sardine regimes. Long-term climate variability seems to be the main cause for interdecadal fluctuations in anchovy fisheries in the HCS, although available time series are too short to prove this link and exclude the hypothesis of nonenvironmental forcing. Large-amplitude regime shifts may be more important to consider than interannual changes since they can affect simultaneously and more dramatically the three anchovy fisheries distributed in the Humboldt Current System. Les variations des captures de trois p?cheries d''anchois du syst?me du courant de Humboldt (HCS) ont ?t? analys?es, ? l''?chelle d?cennale au cours de la p?riode 1960?2002, apr?s ajustement ? l''aide d''un lisseur. Ensuite, les r?sidus de cette relation furent consid?r?s comme repr?sentant les variations interannuelles, donc de fr?quence plus ?lev?e. Les variations des captures sont tr?s coh?rentes entre les trois p?cheries d''anchois du HCS, tandis que l''on observe des diff?rences entre les variations interannuelles r?gionales. Les variations des captures du centre-nord du P?rou ont ?t? similaires ? celles de la p?cherie sud-P?rou/nord-Chili ? l''?chelle interannuelle, et les variations ? cette ?chelle sont corr?l?es n?gativement et de fa?on significative avec les ?v?nements El Ni?o de l''Oscillation australe (ENSO) du Pacifique ayant lieu au cours du printemps austral de l''ann?e ant?rieure. Les variations synchrones, ? l''?chelle d?cennale, des captures des trois p?cheries d''anchois sugg?rent un for?age commun par des facteurs environnementaux du HCS ? la m?me ?chelle temporelle, bien que d''autres causes ne puissent ?tre exclues. Au cours des 40 derni?res ann?es, des variations coh?rentes ont ?t? observ?es et ces changements synchrones sont en opposition de phase avec des "r?gime de sardine". Les variations climatiques interannuelles et interd?cennales semblent ?tre ? l''origine des fluctuations des captures d''anchois dans le HCS, bien que les s?ries chronologiques soient trop courtes pour prouver l''existence de ces liens et exclure l''hypoth?se d''un for?age nonenvironnemental. Les changements de r?gime de grande amplitude semblent plus importants ? prendre en compte que la variabilit? interannuelle car ils affectent simultan?ment et de fa?on plus intense les trois p?cheries d''anchois du HCS. [ABSTRACT FROM AUTHOR] more...

In this study 1047 samples of European anchovy Engraulis encrasicolus caught in 2001, 2002 and 2003 in different areas of the Bay of Biscay were examined using otolith shape analysis. For the years 2001 and 2003, 1 year-old individuals were dominant, whereas for the year 2002 they were less common; in contrast 2 year-old individuals represented 74% of the total individuals, suggesting that the fisheries in 2002 were mainly supported by the strong recruitment of 2000. The classification success of the discriminant analysis indicated a strong separation between year groups ( P < 0·001), overall, 98% of individuals were correctly classified. Results from both jackknife and Cohen’s kappa procedures confirmed the high rates of classification success obtained by the discriminant analysis (99 and 97%, respectively). Stability in the intraannual shape analysis leads to the idea that individuals were affected by the same intraannual environmental conditions in the Bay of Biscay. Variability in the interannual shape analysis could indicate that the spawning population is composed of European anchovy from different origins every year. In general differences observed suggested that the European anchovy in the Bay of Biscay were members of three or more different communities or entities. [ABSTRACT FROM AUTHOR] more...

Larval Pacific anchovy Engraulis japonicus were sampled from coastal waters off the central west coast of Korea from June to November 1996. Using otolith microstructure analysis (daily growth increments), three cohorts (spring, early summer and late summer) were distinguished based on backcalculated spawning dates. Growth rates differed between cohorts, with higher growth rates for late-summer cohorts than either the spring or early-summer cohorts. Growth rate was positively related to surface water temperature, with an optimum temperature range of between 20 and 26° C occurring during the late summer (late July through to mid-September). The study highlights that early growth rates of Pacific anchovy are dependent on ecosystem (particularly water temperature) attributes during early life. [ABSTRACT FROM AUTHOR] more...

The feasibility of using airborne lidar (Light Detection and Ranging) was studied to assess the early juvenile fractions of the main pelagic fish species of the coastal Atlantic waters of southern Europe (anchovy, sardine, mackerel, and horse mackerel). Field comparisons with more established echosounder methods were undertaken in the summers of 1998 and 1999 during the recruitment period of sardine and anchovy in the selected areas, in the presence of a variety of oceanographic and environmental conditions. Backscattered energies as well as the types of target recorded by both devices were compared. The distributions of energies and the shape of the targets were generally similar for both techniques, with moderate numerical correlation between sensors, demonstrating the potential of lidar for assessment of anchovy, sardine, and juvenile mackerel. However, differences in received backscattering energy were found, especially in the presence of certain plankton assemblages (to which lidar is more sensitive) and isolated schools with large vertical dimensions (for which shadowing is more significant for light than sound). Experimental ad hoc optical reflectivity measurements of fish and plankton are proposed to discriminate these two types of targets. In addition, an improvement on lidar implementation and data processing is suggested to achieve fish abundance estimates. [Copyright &y& Elsevier] more...

The anchovy Engraulis encrasicolus is an important fishery resource in the Adriatic Sea. Fluctuating recruitment of young fish to the stock over time can be related to changes in the environment. The trend of anchovy recruitment in the northern and central Adriatic from 1975 to 2001 was analysed with the aim of identifying possible effects related to 5 environmental factors: surface air temperature, surface atmospheric pressure, quadrant specific wind stresses, Po River runoff and North Atlantic Oscillation (NAO) index. Particular emphasis was placed on 1987, a year of anchovy collapse and fishery crisis. Different types of regression models were applied, both linear and nonlinear (simple and multiple), with predictor variables being environmental factors and parental stock abundance. Positive relationships of number of recruits with autumnal SSE and ESE wind stress and both annual and autumnal Po River runoff were found, with a strength comparable to the relationship between recruits and parental stock. Low levels of these environmental factors were observed just before the 1987 collapse, together with a high frequency of occurrence of NE winds and an extreme positive value of the NAO index in the previous autumn (which may have been unfavourable to recruitment in 1987). All 5 environmental factors could be related to increased or reduced food availability for young stages of anchovy in autumn. [ABSTRACT FROM AUTHOR] more...

Feeding habits and gill raker morphology were examined for the three major planktivorous pelagic fishes, Japanese anchovy Engraulis japonicus, Pacific round herring Etrumeus teres and Japanese jack mackerel Trachurus japonicus, off the northern and western coasts of Kyushu, in the north-eastern part of the East China Sea in the summer months of 2001. Using fishes in the same size range (80–140 mm, standard length), the stomach contents of the three fish species were compared. The diet of the Japanese anchovy mainly consisted of Oncaeidae copepods, while the diets of the Pacific round herring and Japanese jack mackerel were dominated by calanoid copepods at all stations. Comparisons between prey size in the stomach, zooplankton size in the water and gill raker morphology suggested that the stomach contents of the three species were characterized mainly by the difference in the feeding behaviour between Japanese anchovy (filter-feeding) and the other two species (particulate-feeding), rather than by the difference in the morphology of feeding apparatus only. It was concluded that behavioural adaptations in the feeding of these pelagic fishes brought about trophic partitioning to some degree in this pelagic ecosystem in summer. Although the diets of these three species overlapped to some extent, there was still little likelihood of competition between the Japanese anchovy and the other two species. The potential for competition between the Pacific round herring and the Japanese jack mackerel is discussed. [ABSTRACT FROM AUTHOR] more...

In order to simultaneously compare vertical distributions of small pelagic fishes and mesopelagic fishes during the night in the upper 100 m, one oblique and 11 horizontal tows of large-sized (opening area 480 m2) trawl operations were conducted at different depths in the Kuroshio–Oyashio Transition Zone during 20–22 May 1995. While Japanese sardine Sardinops melanostictus and Japanese anchovy Engraulis japonicus were concentrated in the upper 20 m, mackerels Scomber spp. were collected uniformly in the upper 80 m layer. Myctophid fishes Ceratoscopelus warmingii, Diaphus kuroshio, Diogenichthys atlanticus, Myctophum asperum, Notoscopelus spp. mostly N. resplendens, and Symbolophorus californiensis, a gempylid Nealotus tripes, a microstomatid Lipolagus ochotensis and a phosichthyid Vinciguerria nimbaria were dominant components of mesopelagic fishes that ascended to the upper 100 m layer at night, where these mesopelagic fishes concentrated at depths of 20–80 m. In the upper 20 m layer, Japanese anchovy comprised 60% of the total wet weight of all fishes followed by D. atlanticus (3%), C. warmingii (2%) and S. californiensis (2%). Juvenile myctophids were dominant in the upper 20 m layer compared to deeper layers. [ABSTRACT FROM AUTHOR] more...

To explore the potential utility of underutilized fish in the fish sauce industry, fish sauces were prepared from both raw and heat-induced meat of Japanese anchovy Engraulis japonica and rabbit fish Siganus fuscescens using wheat malt, and their quality aspects and sensory properties were assessed. Proximate composition of the fish meat represents protein as the major component (16.0–17.8%), other than moisture. Analyses of free amino acids, peptides including oligopeptides, and organic acids contents in fish sauces revealed suitability of both raw and heat-induced meat of the selected species in commercial fish sauce production. The variations in taste of raw meat fish sauces were species-specific, but the taste of fish sauces from heat-induced meat were similar. [ABSTRACT FROM AUTHOR] more...

Abstract: Batch fecundity and spawning frequency data for Japanese anchovy Engraulis japonicus, as well as sea surface temperature (SST) data, derived from the recent literature, were compared between inshore samples (Sagami Bay) and offshore samples (western North Pacific) of anchovy. The offshore anchovy were heavier in body weight and had heavier ovaries than the same-size inshore anchovy. Relative batch fecundity was positively related with gonadosomatic index (GSI) and SST for both the inshore and offshore anchovy; however, the relationships with GSI and SST differed between these two groups. The relative batch fecundity of the inshore anchovy rapidly decreased as SST decreased, while that of the offshore anchovy decreased rather gradually. Although the level of spawning frequency seemed similar between the two groups, the positive relationships to sea temperature differed: the offshore anchovy would spawn at temperatures ca. 5°C lower as frequently as would the inshore anchovy. Comparison of temperature impacts on reproductive parameters suggested the existence of differences between the inshore and offshore anchovy in their specific spawning ecology. [Copyright &y& Elsevier] more...

Many marine systems are subject to high nutrient loadings together with invasions by exotic species. Devising appropriate management responses is an increasing concern and one that has received relatively little attention from researchers. This paper considers the Black Sea anchovy fishery, which has benefited from the relaxation of a nutrient constraint, but has suffered from competition and predation by an invading comb-jelly (Mnemiopsis leidyi). We examine alternative hypotheses about the mechanism triggering outbreaks of the invader (sea temperatures versus nutrients), and the severity of these outbreaks, to see whether a constant escapement policy might be optimal for this fishery. If nutrient levels serve as the triggering mechanism, we argue a mixed blessing effect may be present, so that the effects of nutrient abatement for the anchovy fishery are uncertain. We specify our model empirically and show that a constant escapement policy would be viable under a scenario of reduced impacts from outbreaks of the invader and that nutrient abatement could be beneficial if nutrients trigger outbreaks. [ABSTRACT FROM AUTHOR] more...

Pilchard (sardine) and anchovy are the main targets of South Africa''s pelagic fishery. This fishery is the country''s second most valuable in monetary terms, and produces the highest annual yield in terms of landed mass (in recent years, a combined catch of the order of 400 000t). It is the most dynamic of South Africa''s main commercial fisheries, because the species targeted are relatively short-lived, often occur in mixed shoals, and experience large fluctuations in abundance. Mixed shoaling causes operational problems for the fishery, because of the inevitability of juvenile pilchard bycatch (of more value as adults for canning) in the anchovy-directed fishery. This operational interaction implies a trade-off between allowable catches for the two species, and hence necessitates that they are managed together. The development of a joint “management procedure” (sensu IWC) for the two species is described. This provides a framework for quantifying this trade-off, subject to the constraint that acceptable levels of risk of “collapse” are not exceeded for either resource. Important new features incorporated in a revision of the procedure implemented in 2002, which have made appreciably enhanced catches from the resources possible, are described. [Copyright &y& Elsevier] more...

The effects of cooking methods (electric oven, grill, microwave, and boiling) on total and heme iron contents of anchovy (Engraulis encrasicholus) were investigated. Effects of cooking methods on total and heme iron contents of anchovy were statistically significant (P<0.05). The highest total and heme iron losses were found in grilled samples (52.6%, 70.4%), and the lowest were found in boiled samples (11.2%, 30.4%). Boiling was the most suitable method in terms of both total and heme iron contents of anchovy. [Copyright &y& Elsevier] more...

The reproductive characteristics of Japanese anchovy, Engraulis japonicus, were studied in Osaka Bay and Wakasa Bay, which are located on each side of Japan. The length of spawning season varied between two bays: 8 months (between April and November) in Osaka Bay and 4 months (between May and August) in Wakasa Bay. The seasonal temperature profiles suggested that not only the onset of spawning in both bays but also the end of spawning in Osaka Bay are highly temperature-dependent, and that the critical temperature is about 15°C. On the other hand, Osaka Bay anchovy collected after July were composed of only small ones (smaller than 10.5cm body length). A comparison of length–weight relationships revealed a better body condition of small Osaka Bay fish than Wakasa Bay fish. It is likely that the Japanese anchovy in Wakasa Bay ceases spawning as early as September in spite of a high temperature, due to their poor nutritional condition. Estimated spawning frequency ranged from 0.40 to 0.88 for Osaka Bay females and from 0.22 to 0.62 for Wakasa Bay females. These values indicate that the Japanese anchovy from two bays spawn at similar intervals of 1.13–2.50 and 1.61–4.55 days. The sizes at first maturity in Osaka Bay and Wakasa Bay were estimated as 7.38 and 8.53cm, respectively. These reproductive characteristics are compared and contrasted with those described for the Japanese anchovy in Sagami Bay. [Copyright &y& Elsevier] more...

Measurements were made of the density and settling velocity of eggs of sardine (Sardina pilchardus) and anchovy (Engraulis encrasicolus), using a density-gradient column. These results were related to observed vertical distributions of eggs obtained from stratified vertical distribution sampling in the Bay of Biscay. Eggs of both species had slightly positive buoyancy in local seawater throughout most of their development until near hatching, when there was a marked increase in density and they became negatively buoyant. The settling velocity of anchovy eggs, which are shaped as prolate ellipsoids, was close to predictions for spherical particles of equivalent volume. An improved model was developed for prediction of the settling velocity of sardine eggs, which are spherical with a relatively large perivitelline volume; this incorporated permeability of the chorion and adjustment of the density of the perivitelline fluid to ambient seawater. Eggs of both species were located mostly in the top 20 m of the water column, in increasing abundance towards the surface. A sub-surface peak of egg abundance was sometimes observed at the pycnocline, particularly where this was pronounced and associated with a low-salinity surface layer. There was a progressive deepening of the depth distributions for successive stages of egg development. Results from this study can be applied for improved plankton sampling of sardine and anchovy eggs and in modelling studies of their vertical distribution. [ABSTRACT FROM AUTHOR] more...

Gonosomatic indices and egg and larval densities observed from 1986 to 2001 suggest that the peak spawning season of the Australian anchovy ( Engraulis australis) in South Australia occurs during January to March (summer and autumn). This coincides with the spawning season of sardine ( Sardinops sagax) and the period when productivity in shelf waters is enhanced by upwelling. Anchovy eggs were abundant throughout gulf and shelf waters, but the highest densities occurred in the northern parts of Spencer Gulf and Gulf St Vincent where sea surface temperatures (SST) were 24–26°C. In contrast, larvae >10 mm total length (TL) were found mainly in shelf waters near upwelling zones where SSTs were relatively low (<20°C) and levels of chlorophyll a (chl a) relatively high. Larvae >15 mm TL were collected only from shelf waters near upwelling zones. The high levels of larval abundance in the upwelling zones may reflect higher levels of recruitment to later stages in these areas compared with the gulfs. The sardine spawns mainly in shelf waters; few eggs and no larvae were collected from the northern gulfs. The abundance of anchovy eggs and larvae in shelf waters increased when sardine abundance was reduced by large-scale mortality events, and decreased as the sardine numbers subsequently recovered. We hypothesize that the upwelling zones provide optimal conditions for the survival of larval anchovy in South Australia, but that anchovy can only utilize these zones effectively when the sardine population is low. At other times, northern gulf waters of South Australia may provide a refuge for the anchovy that the sardine cannot utilize. [ABSTRACT FROM AUTHOR] more...

The feeding habits of albacore Thunnus alalunga (fork length: 48.9–76.2 cm, n = 132) were examined from late spring to early autumn in relation to its northward migration in the transition region between the subtropical and subarctic fronts in the central North Pacific. Samples were collected at night using surface gill nets or during daytime pole-and-line surveys in 2001 and 2002. During May and June, albacore fed mainly on Japanese anchovy Engraulis japonicus, which accounted for 27.2%, 67.0%, and 45.5% of the total stomach contents by number ( Cn), wet weight ( WW), and frequency of occurrence ( F), respectively, and secondarily on the subarctic gonatid squid Gonatopsis borealis ( Cn, 15.8%; WW, 10.8%; F, 28.8%). From July to September, albacore continued to depend on Japanese anchovy ( Cn, 48.2–52.8%; WW, 79.9–95.2%; F, 27.8–85.4%). These results corresponded well with the remarkable rebound of the Japanese anchovy stock since the 1990s. Gonatopsis borealis, the main squid prey from May to June, almost disappeared from the stomachs of albacore from July to September, probably due to the northward migration of this squid to subarctic waters in summer. The feeding impact of albacore on the Japanese anchovy stock in the transition region was conservatively estimated to be from 1400 to 2100 tons per day from late spring to early autumn. [ABSTRACT FROM AUTHOR] more...

Pacific sardine ( Sardinops sagax) and northern anchovy ( Engraulis mordax) eggs exhibited different spatial structure on the scale of 0.75–2.5 km in two egg patches sampled in the Southern California Bight in April 2000. Plankton samples were collected at 4-min intervals with a Continuous Underway Fish Egg Sampler (CUFES) on 5 × 5 km grids centered on surface drifters. Variograms were calculated for sardine and anchovy eggs in Lagrangian coordinates, using abundances of individual developmental stages grouped into daily cohorts. Model variograms for sardine eggs have a low nugget effect, about 10% of the total variance, indicating high autocorrelation between adjacent samples. In contrast, model variograms for anchovy eggs have a high nugget effect of 50–100%, indicating that most of the variance at the scales sampled is spatially unstructured. The difference between observed spatial patterns of sardine and anchovy eggs on this scale may reflect the behavior of the spawning adults: larger, faster, more abundant fish may organize into larger schools with greater structure and mobility that create smoother egg distributions. Size and mobility vary with population size in clupeoids. The current high abundance of sardines and low abundance of anchovy off California agree with the greater autocorrelation of sardine egg samples and the observed tendency for locations of anchovy spawning to be more persistent on the temporal scale of days to weeks. Thus the spatial pattern of eggs and the persistence of spawning areas are suggested to depend on species, population size and age structure, spawning intensity and characteristic physical scales of the spawning habitat. [ABSTRACT FROM AUTHOR] more...

Mechanisms and processes that influence small-scale depth distribution and dispersal of bay anchovy (Anchoa mitchilli) early-life stages are linked to physical and biological conditions and to larval developmental stage. A combination of fixed-station sampling, an axial abundance survey, and environmental monitoring data was used to determine how wind, currents, time of day, physics, developmental stage, and prey and predator abundances interacted to affect the distribution and potential transport of eggs and larvae. Wind-forced circulation patterns altered the depth-specific physical conditions at a fixed station and significantly influenced organism distributions and potential transport. The pycnocline was an important physical feature that structured the depth distribution of the planktonic community: most bay anchovy early-life stages (77%), ctenophores (72%), copepod nauplii (>76%), and Acartia tonsa copepodites (69%) occurred above it. In contrast, 90% of sciaenid eggs, tentatively weakfish (Cynoscion regalis), were found below the pycnocline in waters where dissolved oxygen concentrations were <2.0 mg l-1. The day–night cycle also influenced organism abundances and distributions. Observed diel periodicity in concentrations of bay anchovy and sciaenid eggs, and of bay anchovy larvae >6 mm, probably were consequences of nighttime spawning (eggs) and net evasion during the day (larvae). Diel periodicity in bay anchovy swimbladder inflation also was observed, indicating that larvae apparently migrate to surface waters at dusk to fill their swimbladders. Overall results suggest that wind-forced circulation patterns, below-pycnocline dissolved oxygen conditions, and diel changes in vertical distribution of larvae and their copepod prey have important implications for potential transport of bay anchovy early-life stages. [Copyright &y& Elsevier] more...

We hypothesized that change in the annual population size of guano-producing seabirds (cormorant, Phalacrocorax bougainvillii; booby, Sula variegata; pelican, Pelecanus thagus) is a response to changes in primary and secondary production of the Peruvian upwelling system. We tested this hypothesis by modeling nitrate input through upwelling to the upper layers of the ocean off Peru between 6° and 14°S using data on wind stress and sea surface temperature. The model predicted the amount of carbon fixed by primary production each year from 1925 to 2000, which was then apportioned to the Peruvian anchovy ( Engraulis ringens) biomass and ultimately to the seabird population and the anchovy fishery, the largest single-species fishery on Earth. The model predicted a marked increase in primary production as a consequence of increasing wind stress. It overestimated the anchovy biomass after the collapse of the fishery in 1972, but closely predicted the growth of seabird populations from 1925 to the mid-1960s, and their decline thereafter, explaining about 94% of the variation in seabird numbers from 1925 to 2000. The model indicates the seabirds consumed 14.4% of the available anchovies and, thus, that seabirds consumed 2.3% of the new production, before the development of the anchovy fishery, and only 2.2% of the available anchovies and 0.3% of the new production after the development of the fishery. The model results clarify the roles that environmental and anthropogenic factors may have had in regulating the guano-producing seabird populations. It indicates that the growth of seabird populations from 1925 to 1955 was likely a response to increased productivity of the Peruvian upwelling system and that the subsequent drastic decline in seabird abundance was likely due to competition for food with the fishery, which caught ∼85% of the anchovies, which otherwise would have been available for the seabirds. This model also shows that an increase in oceanic primary production promotes reproductive success and population growth in higher trophic level organisms. [ABSTRACT FROM AUTHOR] more...

Time series analyses (Box–Jenkins models) were used to study the influence of river runoff and wind mixing index on the productivity of the two most abundant species of small pelagic fish exploited in waters surrounding the Ebre (Ebro) River continental shelf (north-western Mediterranean): anchovy ( Engraulis encrasicolus) and sardine ( Sardina pilchardus). River flow and wind were selected because they are known to enhance fertilization and local planktonic production, thus being crucial for the survival of fish larvae. Time series of the two environmental variables and landings of the two species were analysed to extract the trend and seasonality. All series displayed important seasonal and interannual fluctuations. In the long term, landings of anchovy declined while those of sardine increased. At the seasonal scale, landings of anchovy peaked during spring/summer while those of sardine peaked during spring and autumn. Seasonality in landings of anchovy was stronger than in sardine. Concerning the environmental series, monthly average Ebre runoff showed a progressive decline from 1960 until the late 1980s, and the wind mixing index was highest during 1994–96. Within the annual cycle, the minimum river flow occurs from July to October and the wind mixing peaks in winter (December–April, excluding January). The results of the analyses showed a significant correlation between monthly landings of anchovy and freshwater input of the Ebre River during the spawning season of this species (April–August), with a time lag of 12 months. In contrast, monthly landings of sardine were significantly positively correlated with the wind mixing index during the spawning season of this species (November–March), with a lag of 18 months. The results provide evidence of the influence of riverine inputs and wind mixing on the productivity of small pelagic fish in the north-western Mediterranean. The time lags obtained in the relationships stress the importance of river runoff and wind mixing for the early stages of anchovy and sardine, respectively, and their impact on recruitment. [ABSTRACT FROM AUTHOR] more...

A fibrinolytic enzyme, myulchikinase, from a Korean seasoning ingredient, myul-chi-jeot-gal, has been purified to electrophoretic homogeneity. The molecular mass of the myulchikinase was estimated to about 28 kDa by SDS-PAGE and gel filtration. Amino acid sequence of the NH2-terminal of myulchikinase showed significant homology with other fibrinolytic enzymes including trypsin from starfish, katsuwokinase, and rat pancreatic elastase II. The purified myulchikinase hydrolyzed various synthetic substrates with different substrate specificity and cytotoxic to the tumor cell lines. [ABSTRACT FROM AUTHOR] more...

The aim of this study was to determine the quality changes of anchovy (Engraulis engrasicholus, L. 1758) and bluefish (Pomatomus saltatrix, L. 1766) due to a multiple freezing-thawing process. The samples were stored in straphor plate at -30 °C and thawed in a refrigerator (+4 ± 1 °C, 16 h), microwave (180 W, 15 m) and in running water (+21 ± 1 °C, 2h) for 15 day periods. Sensory, pH, total volatile basic nitrogen (TVB-N) and trimethylamine nitrogen (TMA-N) analyses were performed. It was determined that the quality of samples thawed in water and a refrigerator decreased to the "spoiled" level after the 3th thawing process and the quality of samples thawed in a microwave spoiled after the 4th thawing process. However, consumption of the fish after the 1st thawing process is recommended. [ABSTRACT FROM AUTHOR] more...

Of the four major eastern boundary currents, the Humboldt Current (HC) stands out because it is extremely productive, dominated by anchovy dynamics and subject to frequent direct environmental perturbations of the El Nin˜o Southern Oscillation (ENSO). The long-term dynamics of the HC ecosystem are controlled by shifts between alternating anchovy and sardine regimes that restructure the entire ecosystem from phytoplankton to the top predators. These regime shifts are caused by lasting periods of warm or cold temperature anomalies related to the approach or retreat of warm subtropical oceanic waters to the coast of Peru and Chile. Phases with mainly negative temperature anomalies parallel anchovy regimes (1950–1970; 1985 to the present) and the rather warm period from 1970 to 1985 was characterized by sardine dominance. The transition periods (turning points) from one regime to the other were 1968–1970 and 1984–1986. Like an El Nino, the warm periods drastically change trophic relationships in the entire HC ecosystem, exposing the Peruvian anchovy to a multitude of adverse conditions. Positive temperature anomalies off Peru drive the anchovy population close to the coast as the coastal upwelling cells usually offer the coolest environment, thereby substantially decreasing the extent of the areas of anchovy distribution and spawning. This enhances the effects of negative density-dependent processes such as egg and larval cannibalism and dramatically increases its catchability. Increased spatial overlap between anchovies and the warmer water preferring sardines intensifies anchovy egg mortality further as sardines feed heavily on anchovy eggs.Food sources for juvenile and adult anchovies which prey on a mixed diet of phyto- and zooplankton are drastically reduced because of decreased plankton production due to restricted upwelling in warm years, as demonstrated by lower zooplankton and phytoplankton volumes and the diminution of the fraction of large copepods, their main food source.Horse mackerel and mackerel, the main predators of anchovy, increase predation pressure on juvenile and adult anchovies due to extended invasion into the anchovy habitat in warmer years. In contrast to these periods of warm and cold temperature anomalies on the decadal scale, ENSO events do not play an important role for long-term anchovy dynamics, as the anchovy can recover even from strong ENSO events within 1–2 years. Consequently, the strong 1972–1973 ENSO event (in combination with overfishing) was not the cause of the famous crash of the Peruvian anchovy fishery in the 1970s. [Copyright &y& Elsevier] more...

Recruitment of bay anchovy (Anchoa mitchilli) in Chesapeake is related to variability in hydrological conditions and to abundance and spatial distribution of spawning stock biomass (SSB). Midwater-trawl surveys conducted for six years, over the entire 320-km length of the bay, provided information on anchovy SSB, annual spatial patterns of recruitment, and their relationships to variability in the estuarine environment. SSB of anchovy varied sixfold in 1995-2000; it alone explained little variability in young-of-the-year (YOY) recruitment level in October, which varied ninefold. Recruitments were low in 1995 and 1996 (47 and 31 x 109) but higher in 1997-2000 (100 to 265 x 109). During the recruitment process the YOY population migrated upbay before a subsequent fall-winter downbay migration. The extent of the downbay migration by maturing recruits was greatest in years of high freshwater input to the bay. Mean dissolved oxygen (DO) was more important than freshwater input in controlling distribution of SSB and shifts in SSB location between April-May (prespawning) and June-August (spawning) periods. Recruitments of bay anchovy were higher when mean DO was lowest in the downbay region during the spawning season. It is hypothesized that anchovy recruitment level is inversely related to mean DO concentration because low DO is associated with high plankton productivity in Chesapeake Bay. Additionally, low DO conditions may confine most bay anchovy spawners to the downbay region, where production of larvae and juveniles is enhanced. A modified Ricker stock-recruitment model indicated density-compensatory recruitment with respect to SSB and demonstrated the importance of spring-summer DO levels and spatial distribution of SSB as controllers of bay anchovy recruitment. [ABSTRACT FROM AUTHOR] more...

Salted and fermented anchovy sauce spiked with or without N-nitrosodimethylamine (NDMA) and N-nitrosopyrrolidine (NPYR) was irradiated at 0, 5, 10, 15 and 20 kGy. NDMA and NPYR reduction by irradiation was not observed in non-spiked samples at 0 week, while a significant reduction was observed after 4 weeks of storage at 15 °C (P<0.05). In N-nitrosamine spiked samples, a positive effect of irradiation on NDMA and NPYR reduction was observed. NDMA and NPYR levels were decreased by irradiation at 5 kGy or above after storage. Therefore, gamma irradiation has a possibility to reduce N-nitrosamines in salted and fermented anchovy sauce. [Copyright &y& Elsevier] more...

We have studied the relationship between the variations in density of South African anchovy (Engraulisi capensis), sardine (Sardinops sagax) and round herring (Etrumeus whiteheadi) from commercial catch records (1987–1997) and a suite of variables describing the environment. The indicator of density (local fish abundance) used was Catch-per-set, obtained from the more than 130 000 catches made during the 11-year study period. The set of environmental parameters included: temporal (Year, Month, time of day or Hour), spatial (Latitude, Longitude and water Depth), lunar (Moon phase and Moon elevation), and thermal conditions of the environment (sea surface temperature together with indices of thermal frontal intensity and temporal change). Boat length was used to account for fishing gear effects. Previous investigations of this nature have tended to use simple bivariate correlation approaches, which suffer from the problem of covariance between the predictive variable and other environmental- or fisheries related variables not included in the analysis. We have, therefore, adopted a multivariate modelling approach, which identifies relationships between Catch-per-set and each environmental variable, accounting for covariation amongst predictors. Model building consisted of first constructing generalised additive models (GAM) as an exploratory tool to identify the shapes of the relationships, followed by parameterising these relationships using general linear models (GLM) to provide a robust predictive tool. Using this modelling approach, the suite of environmental variables explained 19.6% of the variation in Catch-per-set of anchovy, 33.9% of sardine, and 54.3% of round herring in the final GLM models. Temporal variables (Year, Month, Hour), accounted for the major part of the variability in Catch-per-set but variables derived from SST and the lunar cycle provide insight into the effects of environmental factors on fish behaviour. For instance, it appears that schooling behaviour of anchovy and round herring is affected by the level of solar and lunar illumination but that sardine is not affected. Model results further indicate that anchovies prefer water cooler than about 15 °C, demonstrates a weak tendency to concentrate near thermal fronts and avoids recently upwelled water. The sardine’s preferences seem to be more or less the opposite to anchovy, i.e. it occur further from the coast and tends to concentrate in upwelled water which have been warmed to14–19 °C; it shows no discernible tendency for aggregation near fronts. Round herring Catch-per-set strongly increases with water depth and reach a maximum near the shelf edge; it also demonstrates a notable tendency to concentrate near thermal fronts. SST seems to have no influence on round herring which is most often caught in the 15–18 °C range, typical of SSTs found in the vicinity of the oceanic front. [Copyright &y& Elsevier] more...

Abstract Natural mortality, stock–recruitment relationship and sustainable yield of the anchovy (Engraulis japonicus ) stock in the Yellow Sea were estimated based on acoustic assessments of the wintering anchovy stock from 1987 to 2002. The stock-recruitment relationship was estimated to be: R = 151.1 × SSB × e[sup -0.299·SSB] , where R is given in billion fish and SSB is in million tons. The optimum sustainable yield of anchovy was estimated at 520 000 tons for the period 1987–2002. The ecological consequences of the sharp decline of the anchovy stock observed after 1996 were examined in terms of the reduction in biomass production in the Yellow Sea ecosystem, as well as the consequences of such reduction on predator–prey interactions and species competition. [ABSTRACT FROM AUTHOR] more...

The European Anchovy (Engraulis encrasicolus, Linnaeus, 1758) represents one of the most important fishery resources in some areas of the Mediterranean. This short-lived, small pelagic fish is characterized by large interannual fluctuations, probably as a result of environmental variability. As part of the European Project Med 98-070, the main aim of which was the study of the anchovy population in the Strait of Sicily, icthyoplankton surveys were carried out between 1999 and 2001, during the peak spawning season for anchovy. Present work reports the relationship between meso-zooplankton biomass and the abundance of anchovy eggs and larvae in the Strait of Sicily. Data on anchovy egg abundance showed that the main spawning area was located in the north-western region of the study area. The branch of the Atlantic Ionian Stream, running parallel to the southern Sicilian coast, acts as a transport mechanism for anchovy eggs and larvae towards the southernmost end of the island, off Cape Passero. Observed distributions were largely consistent with local hydrographic features, which allow larvae to be retained in areas providing the necessary feeding conditions for recruitment success. [ABSTRACT FROM AUTHOR] more...

Provides information on a study that investigated the peculiarities of dynamics of the total lipids content and their fractional composition in the body of Azov anchovy. Methodology of the study; Results and discussion on the study; Conclusion. more...

Growth rates of anchovy larvae were estimated from samples collected in the Brazilian Southeastern Bight (BSEB) in June/July and November/December, 1995. Horizontal distribution and abundance of the larvae were determined. The rate of ring formation on the otolith was related to the marginal increments and time of day. The Laird–Gompertz growth model was adjusted to the data and instantaneous growth rates were compared for anchovy larvae of other habitats in the SW Atlantic. Larval growth rates for several stocks were shown to be dependent on environmental conditions and the calculated size at first feeding on the temperature, producing geographical variation of larval growth rate throughout the distribution range of the species. The results suggest that E. anchoita from the BSEB may form a population distinct from stocks already known in more southerly regions. [Copyright &y& Elsevier] more...

The polymorphic enzyme phosphoglucomutase showed a significant genetic change and seasonal excess of homozygotes in two species of anchovy repetitively sampled during the spawning periods over 2 years in the Arabian Gulf. Samples from the peak spawning periods were not in genetic equilibrium, which is unexpected as spawning stocks are thought to show the greatest level of genetic isolation, and indicate that assortative mating may occur. [Copyright &y& Elsevier] more...

Abstract School-size estimates based on information from a sector-scanning sonar were compared with those based on information from an echo sounder. Three pairs of size estimates of anchovy schools in the coastal waters, off Fukuoka Prefecture were shown as examples. They included the possibility of improving the size estimates by using information from sector-scanning sonar to consider the size in the transverse direction. In these examples, the thickness and extent of the school varied in the transverse direction. A large difference was found between the estimates from the sounder information and those from the sector-scanning sonar information, although whether or not the estimated size decreased differed according to each case. Also, whether the thickness information or the extent information is influential differed according to each case. The size information from the sector-scanning sonar in the transverse direction caused a change in the estimated size from 66 to 16 (×103 m3 , mainly by different extent), 305 to 146 (×103 m3 , thickness increased but extent decreased), and 819 to 746 (×103 m3 , three seemingly separated schools fused into one). [ABSTRACT FROM AUTHOR] more...

Explores environmental constraints that select observed spatial and temporal spawning patterns for anchovy in the southern Benguela. Implementation of an evolutionary-based reproductive strategy for adult fish and a passive transport for early life stages; Mean spawning patterns; Constraint of reaching the nursery area. more...

Summaries of maritime weather reports and mean seasonal satellite-sensed ocean colour distributions for the Mediterranean Sea are used to identify characteristic configurations of physical mechanisms promoting (i) nutrient enrichment, (ii) concentration of larval food distributions, and (iii) local retention of eggs and larvae. Five subbasin scale 'ocean triads', hypothesized to be particularly favourable groupings, are identified in the Aegean Sea, the Gulf of Lions and nearby Catalan Coast, the Alboran Sea, the Straits of Sicily/Tunisian Coast, and the Adriatic Sea. These are examined in relation to available knowledge of anchovy spawning grounds. All areas are characterized by patterns of linked wind-driven Ekman upwelling and downwelling. All areas except the Straits of Sicily are found to have inputs of less saline surface waters offering raised nutrient concentrations, enhanced upper layer stability, and frontal density contrasts, and to have areas where the characteristic rate of turbulent mixing energy input by the wind fall below a reference intensity level. All areas, except the Sicilian Channel/Tunisian Coast, also contain abundant locally reproducing anchovy populations. [ABSTRACT FROM AUTHOR] more...

Experiments were performed on salting and ripening of anchovy (Engraulis anchoita). The quality of the raw material, maturation processes and finished product was assessed by sensory, physical and chemical analysis. Physical damage was highly correlated (r² = 0.957) with belly burst. Also, raw material quality influenced ripening time. Comparisons with smoked farmed Atlantic salmon (Salmo salad were made and combined to correlate (r² = 0.972) with final product quality. The results of this research allow the prediction half a year in advance of the quality of the finished product to be obtained, by assessing the raw material quality. As quality improved, costs of the finished product decreased. [ABSTRACT FROM AUTHOR] more...

Three genera, Engraulis, Sardinops, and Merlucciu have coincident spawning and juvenile brood areas in most eastern and western boundary currents throughout the world. The CalCOFI survey program has amassed a 50-year data series on location and timing of spawning and the resultant recruitment of anchovy, sardine, and hake in the California Current region. Use of existing Lefkovitch matrix population projection models for these three species allows evaluation of the spatial and temporal scales that govern the biological and physical interactions. We present rate diagrams for hake and construct comparable diagrams for anchovy and sardine in a common, variable environment. Rate diagrams depict the relative importance of demographic (natality and mortality), growth, and kinematic (passive and active movement) processes to a quantity of interest as a function of spatial and temporal scale. Results confirm that the scale of observations will have to be manipulated to expose the importance of any combination of processes for life history stages among these species. Field sampling systems have not yet responded adequately to mesoscale features (50 km) persisting over months. [ABSTRACT FROM PUBLISHER] more...

As the world's marine ecosystems deteriorate due to pollution and overfishing, there is an urgent need to investigate links between the two problems. We assess the effects of improving environmental quality in the presence of such linkages, recognizing that the impact of pollution on fisheries may be complex and that efficiency benefits from pollution control may be limited in open-access fisheries. Using a dynamic bioeconomic modeling approach, we incorporate habitat quality in the presence of ecological 'regime shifts' and analyze the comparative static effects of an exogenous reduction in nutrient inputs. We apply the approach to the Black Sea anchovy fishery, where the introduction of an exotic comb jelly caused the 'regime shift.' We show that pollution abatement significantly raises catch, employment, and revenues at the long-run equilibrium of the system, but only if abatement prevents the regime shift. Ultimately, for substantial efficiency benefits to arise from nutrient abatement, the open-access problem must be addressed as well. [ABSTRACT FROM AUTHOR] more...