Engraulid Fish Research Articles

Community ecology of the metazoan parasites of the Atlantic anchoveta, Cetengraulis edentulus (Actinopterygii: Engraulidae) from the Sepetiba Bay, Rio de Janeiro, Brazil

The Atlantic anchoveta, Cetengraulis edentulus (Cuvier, 1829) is one of the most commercially important fish species in the littoral of Brazil. The present study evaluates the parasitic fauna of this engraulid fish from the southeastern Brazilian coast. Between October 2019 and March 2020, a total of 100 specimens of C. edentulus from the Sepetiba Bay, Rio de Janeiro, Brazil (22°57’44”S; 43°52’28”W), were examined. Eighty-five specimens of C. edentulus were parasitized by at least one species of metazoan, with a mean of 4.32 ± 6.12 parasites/fish. Eleven species of parasites were collected: five digeneans, two monogeneans, two copepods, one isopod and one nematode. The nematode Hysterothylacium sp. was the most abundant and dominant species, representing 51.85% of the metazoan parasites collected, showing positive correlation with the host’s total length and parasite abundance and prevalence. The mean abundance and prevalence of Hysterothylacium sp. was significantly higher in female hosts. One pair of larval endoparasites showed positive covariation. Centengraulis edentulus represents a new host record for nine species of parasites. A dominance of endoparasitic larval stages is documented in the parasite community of C. edentulus. This may be a function of the feeding habits of engraulid fish, which feed mainly on zooplanktonic organisms. It may also have to do with to the fact that C. edentulus is the intermediate and/or paratenic host of fish parasites, birds, and marine mammals.

Diet composition and trophic niche similarities of engraulid fishes in Pabean bay, Indramayu, Indonesia

A study on the trophic ecology of fishes is one of the approaches to acquire a better understanding of fish feeding strategies, prey inclinations, niche competition and increase knowledge on the working of marine biological system. The present work aims to determine diet composition and trophic niche overlap among species of engraulid fishes in the coastal area of Pabean. Sampling was performed monthly from April 2016 to March 2017 and fishes were captured using gill nets and guiding barriers. During research period, seven species of engraulid were collected, namely Thryssa hamiltonii (with total length ranged from 47-186 mm), Thryssa mystax (53-151 mm), Thryssa kammalensis (66-112 mm), Thryssa setirostris (106-132 mm), Stolephorus indicus (54-133 mm), Stolephorus dubiosus (56-75 mm) and Stolephorus tri (66-91 mm). Prey of fishes were classified into four taxonomic groups i.e., Bacillariophyceae, Polychaeta, Crustacea and Pisces. Crustacea was the most consumed category (IRI>90%), recorded for all species of engraulid fishes, followed by Bacillariophyceae (<10%), polychaeta and fish juveniles (<5%). This finding indicates that all engraulid fishes in Pabean waters are crustasivore. Inter-specific feeding overlap was high, indicates that feeding competition among engraulid fishes tends to be high when food resources is decreased.

Hábitos alimenticios del sable Trichiurus lepturus en el Golfo de Urabá, Caribe colombiano

Se estudiaron los hábitos alimenticios del pez comercial Trichiurus lepturus, un mesodepredador con un papel importante en el flujo de energía en las redes tróficas costeras, con el objeto de contribuir al conocimiento de su ecología, herramienta para su conservación e insumo para el ordenamiento pesquero del Golfo de Urabá, en el noroeste de Colombia. Usando redes de enmalle se capturaron 320 individuos, de los que se obtuvieron 208 estómagos con contenido. El espectro alimenticio de la especie está integrado por 26 ítems, pertenecientes a tres grandes grupos taxonómicos: peces, crustáceos y moluscos. Entre estos, los engráulidos (Engraulidae) son el principal componente en todos los sitios de muestreo, sobresaliendo Centengraulis edentulus y varias especies del género Anchoa. Se encontró un traslape de presas entre los sitios, siendo evidente la importancia de las áreas de manglar para alimentación. Sin embargo, no hubo variación estacional ni diferencias entre sexos en la composición de la dieta, dado que los engráulidos, su principal presa, son uno de los recursos pesqueros más abundantes en el Caribe colombiano.

Feeding habits and trophic status of Merluccius hubbsi along the northernmost limit of its distribution in the South-western Atlantic

AbstractStomach contents analysis and stable isotope results indicate M. hubbsi is a generalist predator that feeds mainly on demersal fishes, followed by crustaceans and cephalopods. Ontogenetic changes in diet were identified, with fish importance increasing in the diet with hake size. Smaller hake (&amp;lt;250 mm) fed mostly on the sepiolid Semirossia tenera (89.45%IRI) and engraulid fish (89.96%IRI). Mid-sized hake (250–300 mm) fed mainly on benthic fish such as Bellator brachychir (95.63%IRI) and euphausiids (56.46%IRI), while larger hake (&amp;gt;300 mm) fed heavily on Dactylopterus volitans (94.80%IRI) and occasionally on a variety of teleosts. Significant correlations between δ13C (P &amp;lt; 0.05), THg (P &amp;lt; 0.001) and hake size occurred, whereas no relationship was observed between δ15N and hake size or δ15N and total mercury. Signatures were lowest in smaller hake with a tendency of increasing with size. Smaller and larger hake were significantly different in δ13C. Differences regarding isotopic niche width were quantified for each size group; trophic diversity and trophic redundancy among them were negligible, but hake &amp;gt;300 mm possibly have a larger feeding plasticity due to the combination of prey from a wide trophic level range.

Unravelling habitat use of Coilia nasus from the Rokkaku River and Chikugo River estuaries of Japan by otolith strontium and calcium

The migratory history of the engraulid fish Coilia nasus in the Rokkaku and Chikugo River estuaries of the Ariake Sea, Japan was assessed using otolith strontium (Sr) X-ray intensity maps and strontium:calcium (Sr:Ca) ratio life history transects by an electron probe microanalyzer (EPMA). The results showed that seven of the ten specimens from the Rokkaku River Estuary (LJC) and all 15 specimens collected in the Chikugo River Estuary (ZHC) had low Sr:Ca ratios (⩽3) at the central otolith area, indicating their riverine origin and initial freshwater residence. After the first regime shift adjacent to natal regions, the Sr level mapping displayed a wide variety of color patterns, and the Sr:Ca ratios obtained by the line transect analysis could be divided into one to six significantly different phases indicative of gradual life history transition. The other three specimens from the Rokkaku River Estuary had high Sr:Ca ratios (3–6.7) at the central otolith area but showed alternating changes between low and high values outside the natal region, suggesting that estuarine-origin individuals occurred in the Rokkaku River Estuary. The two-dimensional maps of the Sr level and average of the otolith Sr:Ca ratios along the life-history transects could be used as effective tools for reconstruction of past habitat use of the tapertail anchovy in estuaries of the Ariake Sea, Japan.

Diet Composition and Feeding Habits of Two Engraulid Fish Larvae (Engraulis Japonicus and Coilia Nasus) in the Nakdong River Estuary, Korea

Choi, H.C.; Youn, S.H.; Huh, S.-H., and Park, J.M., 2018. Diet composition and feeding habits of two engraulid fish larvae (Engraulis japonicus and Coilia nasus) in the Nakdong River estuary, Korea. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 346–350. Coconut Creek (Florida), ISSN 0749-0208.Engraulis japonicus and Coilia nasus are members of the family Engraulidae, and their larvae are important components in the estuarian ecosystems that they inhabit. The dietary study of fish larvae is essential to understanding early survival and recruitment in fish populations. This study investigated the dietary compositions and size-related dietary changes in E. japonicus and C. nasus larvae in the Nakdong River estuary. Larvae samples were collected monthly between April and August 2011 using an RN80 net at two stations in the estuary. Gut content analyses revealed that E. japonicus fed mostly on copepods, and secondarily on tintinnids and cladocerans, while C. nasus preferred to consume freshwater cladocerans. These dietary differences between the two larvae were closely related with habitat preference, which provided different local prey sources at each station. As the larvae of both species grew, the consumption of copepods for E. japonicus, and cladocerans for C. nasus, gradually increased, indicating distinct ontogenetic dietary changes. This dietary study of larval E. japonicus and C. nasus is important information for the development of fisheries, and can be implemented in related further studies of areas other than estuaries.

Selective predation by crevalle jack Caranx caninus on engraulid fishes in the SE Gulf of California, Mexico

Feeding habits determine many aspects of living organisms, where it lives, the time of day that it is active, energy flow, biomass consumed and intra- and interspecific interactions, it which provides information to make predictions about the effects of fisheries on predator-prey relationships. Accurate predictions require a thorough understanding of predator diets and prey selection. In this study, specimens of the crevalle jack Caranx caninus were obtained between October 2012 and October 2014 in the SE Gulf of California, Mexico, in order to determine its feeding habits and prey selection. A total of 238 specimens were obtained, of which 94 (39.5%) had stomachs containing food and 144 (60.5%) had empty stomachs. A total of 10 prey items were identified, corresponding to seven families that included fishes, crustaceans and cephalopods. According to the Index of Relative Importance (IRI) the most important prey were Anchoa spp. (IRI = 91.2%), Engraulis mordax (IRI = 1.8%), and fish from the Clupeidae family (IRI = 1.0%). The crevalle jack’s diet did not change with the season (warm or cold). The crevalle jack was considered a tertiary predator (trophic level = 4.3) that tends to feed on a reduced number of prey, characterizing it as a specialist and selective predator of engraulid fishes (Levin’s index, Bi = 0.08; E = 0.6).

Three species of Heteromazocraes Mamaev, 1981 (Monogenea: Mazocraeidae), including two new species from Thryssa spp. (Teleostei: Engraulidae) off Visakhapatnam coast, Bay of Bengal.

Three species of Heteromazocraes Mamaev, 1981 including two new taxa are described from the gills of three species of engraulid fishes Thryssa mystax (Bloch & Schneider), T. setirostris (Broussonet) and T. malabarica (Bloch) collected from the coastal waters off Visakhapatnam, Bay of Bengal. Heteromazocraes thryssaensis n. sp. differs from the closely related H. dodecacantha Mamaev, 1981 in the shape of the body and ovary, the number of testes and the number and shape of the genital hooks. Heteromazocraes engrauliae n. sp. differs from all the other species of the genus in the relative sizes of the haptoral clamps, in that the four closed clamps on the left side are larger than the two open clamps on the right side, in contrast to the situation in other species where the two open clamps on the anterior right side are markedly larger than the remaining clamps. Heteromazocraes kazikodiensis (Gupta & Khullar, 1967) Mamaev, 1981 regarded as a species inquirenda is redescribed with additional details and is reinstated as a valid species. A review of Heteromazocraes including a key for identification of the species is provided.

Population structure of the monogenean, Paramazocraes thrissocles (Mazocraeidae) on the gills of clupeoid fish, Thryssa mystax of Visakhapatnam coast, Bay of Bengal.

An investigation was undertaken on the population biology of the mazocraeid monogenean Paramazocreas thrissocles occurring on the gills of the engraulid fish Thryssa mystax at Visakhapatnam coast , Bay of Bengal. The influence of season and host size on the parasite population density and the dispersion pattern of the parasite in the host population were analysed. A distinct seasonal pattern in the prevalence and intensity to infection is noted with higher parasite loads prevailing during warmer summer months and very low or no infection during winter months. The heavy infections are found to be promoted by high temperatures prevailing during summer months coupled with high host density and the larger size of fish examined during this period. A positive correlation between host size and prevalence and mean intensity to infection with the monogenean was noted, larger fish often carrying heavy infections. Further the monogenean showed an aggregated distribution on the host population as evidenced by the low value of negative binomial parameter 'K'.

鹿児島県から採集された日本初記録のカタクチイワシ科魚類シロガネアイノコイワシ（新称） Encrasicholina devisi および近縁種との比較

鹿児島県から採集された日本初記録のカタクチイワシ科魚類シロガネアイノコイワシ（新称） Encrasicholina devisi および近縁種との比較

Microdistribution and feeding dynamics of Coilia nasus (Engraulidae) larvae and juveniles in relation to the estuarine turbidity maximum of the macrotidal Chikugo River estuary, Ariake Sea, Japan

AbstractTo evaluate the nursery value of the estuarine turbidity maximum (ETM) for the anadromous engraulid fish Coilia nasus, physical and biological samples were collected along the macrotidal Chikugo River estuary, southwestern Japan, from June 2005 to January 2006. Generally, eggs were distributed upstream of the ETM, whereas larvae were distributed in the ETM. The first cohort was washed out of the estuary by a large flood in early July. The second cohort appeared after the flood, gradually extending its distributional area through the estuary and growing to 100 mm in standard length (SL) by December. Larvae and juveniles (20–100 mm SL) fed selectively on copepods, specifically large calanoid species, whereas more developed juveniles fed on mysids. Prey organisms in guts were significantly more abundant and present in greater weights in the ETM (salinity &lt;10) than in the lower estuary (salinity &gt;10). The better feeding conditions were primarily attributable to consistently high densities of two large calanoid species, Sinocalanus sinensis and Pseudodiaptomus inopinus, in the ETM. In contrast, the poor feeding conditions in the lower estuary were likely due to a seasonal decrease in copepod density and the dominance of small copepods such as Oithona spp. Given that better feeding conditions contribute positively to the growth and survival of larvae and juveniles, we conclude that the ETM has a significantly higher nursery value for C. nasus compared with other habitats in the Chikugo River estuary.

The Food of &lt;I&gt;Selene Peruviana&lt;/I&gt; (Actinopterygii: Perciformes: Carangidae) in the Southern Gulf of California

Background. The food and feeding habits of a fish are important for understanding not only the fish biology but also the role played by the species in the ecosystem. The Peruvian moonfish (known also as Pacific moonfish), Selene peruviana (Guichenot, 1866), is a relatively abundant species, with its biology poorly known along the Mexican Pacific zone. Therefore, the aim of this study was to determine the principal food items of the Peruvian moonfish by using stable isotopes and the stomach content analysis. Materials and methods. We analyzed stomachs of 204 moonfish collected by a shrimp fishing boat along the coast of Nayarit and south of Sinaloa, Mexico from September to March, within 2006-2007. We also took 11 muscle samples of moonfish and some organisms being potential prey items for stable isotope analysis. Examining the stomach contents we determined the most important prey species using the geometric index of importance. We also determined the feeding strategy of this predator using Amundsen plots and Levin's index and finally we calculated the trophic position. We also determined the principal preys using stable isotopes analy- sis along with mixing models, and based on those values we calculated the trophic position. Results. The stomachs of Selene peruviana contained chiefly engraulid fishes and crustaceans. The stable iso- topes analysis (SIA) helped to identify partly digested material as representing crustaceans of the family Portunidae. The trophic position found by both methods was between 3.7 and 3.9 and we also determined that this fish tended to feed near the coast. Conclusion. Selene peruviana is an opportunistic predator that consumes preys that are abundant in the zone. The stable isotopes analysis proved to be an efficient tool supplementing the stomach content analysis and helping to identify also partly digested items.

Three cone opsin genes determine the properties of the visual spectra in the Japanese anchovy Engraulis japonicus (Engraulidae, Teleostei)

A complement of cone visual pigments was identified in the Japanese anchovy Engraulis japonicus, one of the engraulid fish species that has a retina specialized for polarization and color vision. The nature of the chromophore bound to opsin proteins was investigated using high performance liquid chromatography. The opsin genes were then cloned and sequenced, and the absorption spectra of different types of cones were obtained by microspectrophotometry. Two green (EJ-RH2-1, EJ-RH2-2) and one red (EJ-LWS) cone opsin genes were identified and are presumably related to the vitamin A1-based visual pigments (i.e. rhodopsins) with λmax values of 492, 474 and 512 nm, respectively. The long and short cones from the ventro-temporal retinal zone consisted of a pure population of RH2 class gene-based pigments (λmax=492 nm). The long and short cones from other retinal areas and the lateral components of the triple cones possessed a mixture of RH2 and LWS class gene-based pigments that exhibited a λmax of ~502 nm. The central component of the triple cones contained only RH2 class gene-based pigments (λmax=474 nm). Thus, E. japonicus possesses a middle-wave range of spectral sensitivity and acquires different color vision systems in distinct visual fields.

SALT WATER INTRUSION AND ITS RELATIONSHIP WITH ESTUARINE ECOLOGY IN THE CHIKUGOGAWA ESTUARY

The spatiotemporal distribution of seawater intrusion in the Chikugogawa estuary was analyzed, and its relationship with the temporal variation of phytoplankton and engraulid fish, Coilia nasus, was discussed. The Chikugogawa estuary is vertically well mixed for most of the year, and a salt wedge is observed only when the tidal range decreases to 2 m or less. We found that the ratio of chlorophyll-a to pheophytin-a during the semilunar cycle varied according to the change in the mixing conditions in the estuary. Further, the number of sampled estuarine fish was related to the salinity and tidal range within the estuary; the fish was caught when the salinity was low and the tidal range was large. It is necessary to regulate the fresh water discharge in the estuary in order to maintain a low-salinity region that is suitable for the migration of fish and their spawning areas to the downstream of the river mouth barrage.

Spawning Area and Time of an Engraulid Fish, Coilia nasus in Chikugo River

Spawning Area and Time of an Engraulid Fish, Coilia nasus in Chikugo River

Mazocraeid Monogeneans Parasitic on Engraulid Fishes in the Southwest Atlantic

Two species of mazocraeid monogeneans are reported for the first time from Argentinean-Uruguayan engraulid fish hosts, Engraulis anchoita and Anchoa marini. Mazocraes australis n. sp. collected from the gills of E. anchoita is described: this new species can be distinguished from the other congenerics by the number of genital hooks in the copulatory organ, the relative size of clamps, and the number of hooks in the terminal lappet. Pseudanthocotyloides heterocotyle found in the gills of E. anchoita and A. marini is redescribed. The diagnosis of both mazocraeid genera are also emended.

Myxosporeans and coccidians parasitic on engraulid fishes from the coasts of Argentina and Uruguay.

Two new species of the genus Sphaeromyxa (Myxosporea) from the gall bladder and one new species of the genus Eimeria (Coccidia) parasitizing the testes, are reported from engraulid fishes from the Argentinian shelf (including the Argentinean-Uruguayan Common Fishing Zone): Sphaeromyxa bonaerensis n. sp., found in Engraulis anchoita Hubbs & Marini, 1935 (argentine anchovy) (prevalence 0.2%) and in Anchoa marini Hildebrand, 1943 (anchovy) (prevalence 24.2%) caught in the Bonaerense region of the Argentinian Sea; Sphaeromyxa argentinensis n. sp. found in E. anchoita from all the sampled localities between 34 degrees S and 46 degrees S (prevalence 26.8%) and from A. marini at Mar del Plata coastal zone (prevalence 1.01%). Eimeria patagonensis n. sp. was found in E. anchoita living in the Patagonian region of the Argentine Sea (prevalence 0.45%). Details of some ultrastructural features of S. argentinensis are provided.

Laboratory Reared Eggs and Larvae and Subsequent Stages from Plankton of Vellar Estuary, Porto Novo- Part I - The Engraulid Fish, &lt;i&gt;Thryssa mystak&lt;/i&gt; (Schneider)

Laboratory Reared Eggs and Larvae and Subsequent Stages from Plankton of Vellar Estuary, Porto Novo- Part I - The Engraulid Fish, &lt;i&gt;Thryssa mystak&lt;/i&gt; (Schneider)

On the Occurrence of the Engraulid Fish, Stolephorus buccaneeri Strasburg, in the Oceanic Region of the Equatorial Western Pacific : Life History and Distribution

Larvae of Stolephorus buccaneeri previously reported only from coastal waters, were collected dominantly with larva nets in the oceanic regions of the Equatorial Western Pacific during the cruises of R/V Shunyo-maru and R/V Hakuho-maru. The development from larva (3.2 mm SL) to adult (39.5 mm SL) is described. The following changes of body form are characteristic of engraulid fishes; slender body deepens, head becomes round and mouth inferior, dorsal and anal fins shift anteriorly; with rapid changes shortly after 15 mm SL, the juvenile assumes almost the adult form. The melanophores typical of the postlarva are restricted to the ventral surface and show strongly throughout development; those of the adult first appear at a late postlarval stage. It was found that after the late postlarval stage the developmental sequence is subject to intraspecific variation correlated with distribution, the more oceanic the fish the earlier the changes to adult form occur. In Hakuho-maru samples, postlarva of just over 15 mm SL changes morphologically more rapidly, to reach the juvenile stage at about only 25 mm SL; the size of the adults is less than 40 mm SL. Brain form of S. buccaneeri was compared with that of four other Stolephorus species taken in the neritic waters. The oblong telencephalon and relatively long bulbus olfactorius were found to be characteristic of S. buccaneeri, although intraspecific variation was found. The brain of the oceanic specimens is well separated from the skull and has a slender telencephalon, in contrast with that abutting on the skull and the oblong telencephalon in the neritic specimens. The larval occurrence was independent of the direction of the surface currents and the composition of samples was similar in the oceanic regions. The results of collections by MTD horizontal closing nets in the upper 500 m indicate that these larvae are limited to surface water. It is concluded that S. buccaneeri probably inhabits and completes its life history both in oceanic and neritic waters throughout the whole West Pacific region. According to analysis by t-test, meristic counts did not show highly significant differences (P<O.Ol) among 6 samples taken in different areas (three oceanic, the others neritic). The results support the assumption that the species may occur as an immigrant into neritic waters.

Variation, Distribution, and Ecology of Anchoviella analis, an Engraulid Fish from the Pacific Slope of Mexico

Variation, Distribution, and Ecology of Anchoviella analis, an Engraulid Fish from the Pacific Slope of Mexico