Atlantic Herring Clupea Harengus Research Articles

Spawning of Herring in Milford Haven

Information regarding spawning grounds of the Atlantic herring Clupea harengus Linnaeus has been based mainly on the collection of spawning fish, newly hatched larvae, or the presence of eggs within the stomachs of predators (Postuma, Saville & Wood, 1977). This type of evidence indicates general areas of spawning, rather than accurately delineating the spawning grounds. Though samples of spawn have been obtained from several localities in the North-East Atlantic (Ewart, 1884; Runnström, 1941; Fridriksson & Timmerman, 1951; Bolster & Bridger, 1957; Parrish et al. 1959; Hemmings, 1965; Bowers, 1969; Anthony, Sauskan & Sigaer, 1970), few quantitative studies of individual grounds have been made. In consequence, little is known of the factors influencing the selection of grounds by Atlantic herring, the shape of these grounds and egg distribution within spawning areas.

Mortality, Growth, and Transport of Larval Atlantic Herring Clupea harengus in Maine Coastal Waters

Abstract Microstructural growth increments in otoliths of autumn-spawned, larval Atlantic herring from the Sheepscot River estuary of western Maine and Sullivan Harbor of eastern Maine provided estimates of mortality, growth, or transport times (or combinations of these) for 19 cohorts in 1980–1982. Mortality within seven cohorts averaged 2%/d (range, 0.7–3.1%/d). Growth (12 cohorts) averaged 0.199 mm/d (0.123–0.270). Transport times of larvae hatched on the spawning ground of eastern Maine and captured in the harbor and estuary (8 cohorts) averaged 16.5 d (5–35 d). Estimates of mortalities agreed (P > 0.05) with those from multicohorts obtained in the 1960s and 1970s (0.4–3.2%/d). Among the cohorts, extremes of larval growth differed significantly (P 0.05) was noted between larvae of cohorts spawned relatively early and those of a cohort spawned late. Larval mortality and growth appeared...

Stock Assessment Problems in Atlantic Herring (Clupea harengus) in the Northwest Atlantic

Total annual catches of Atlantic herring (Clupea harengus) in NAFO statistical areas 3–6 have declined steadily since 1968, and have not rebounded after management measures were implemented in the late 1970's (unlike demersal species in the area). The accuracy of the biomass estimates generated by sequential population analysis is evaluated by a retrospective analysis for 3 of the 10 management units for herring fisheries. In each case, the stock assessments have tended to seriously underestimate the declines in stock abundance and overestimate the upswings. Fishing mortalities have exceeded F0.1, but they have rarely exceeded Fmax, the level below which growth overfishing is prevented. Three assumptions in the stock assessment process are evaluated in relation to the 4WX management unit: (1) the various management units are in fact self-sustaining populations; (2) catchability (i.e. fishing mortality per unit of effort) is constant and independent of stock size; and (3) the population is in the stable age distribution. We conclude that at least part of the management failures are due to invalid assumptions in the stock assessment models. An approach that has prevented growth overfishing may well have caused recruitment overfishing. Atlantic herring should be managed on principles suited to salmon rather than those applied to groundfish.

Selection of External Tags for Marking Atlantic Herring (Clupea harengus harengus)

Of seven external tags (carlin, disc and disc, disc and dangler, anchor, short anchor, dart, streamer) applied to Atlantic herring (Clupea harengus harengus), the anchor tag is the best to use when tagging rate, recovery rate, and persistence of tagged fish in the population are considered. A high recovery rate for carlin tags was more than compensated by the higher application rate exhibited by anchor and dart tags. Anchor tagged fish had a lower sustained mortality and reduced time in setting up the tags for application compared to dart tags. Tagged herring suffered higher short and apparent long-term mortalities than the unmarked population regardless of which external tag type was applied. Long-term tag loss may have been due to tag induced mortality and/or tag shedding. Consequently, studies requiring data beyond 2 yr after release would need another type of tag. Initial mortalities of herring increased with holding and handling time for all tags tested. This result confirms that herring should be tagged immediately after capture to reduce initial mortalities.

Consideration of the Stable Age Distribution Assumption in "Analytical" Yield Models

The implications on the "analytical" yield model of deviations from the stable age distribution were investigated for stocks of five species with a range of life history characteristics, these being Atlantic cod (Gadus morhua), haddock (Melanogrammus aeglefinus), pollock (Pollachius virens), Atlantic herring (Clupea harengus harengus), and Atlantic mackerel (Scomber scrombus). Recruitment variability for the stocks considered ranged from 21% for pollock to 104% for haddock. The comparison of the growth rates at age for the five species showed the expected continuum in relative growth rates from cod to mackerel. With the population in a stable age distribution without fishing there is also a continuum from cod to mackerel in the manner in which age-specific production decreases through the life span. It is thus to be expected that deviations from the stable age distributions for mackerel would have a much greater impact on population production than would a similar deviation for cod. Also, species whose growth rates decrease more rapidly with age tend to have a higher recruitment variability. To demonstrate the implications of deviations from the stable age distribution on the accuracy of model output, MSY yields (that would have been generated given historical estimates of population numbers-at-age) were compared to estimates of annual population production. Cod and pollock production deviate relatively little from the "analytical" model predictions. In contrast, annual production for haddock, herring, and mackerel deviate markedly from MSY yields as the age composition deviates in each direction from the stable age distribution. The analysis suggests that for some species the "analytical" model may contribute to growth overfishing.Key words: "analytical" yield models, stable age distribution, growth overfishing

Stock Definition in Atlantic Herring (Clupea harengus harengus): Genetic Evidence for Discrete Fall and Spring Spawning Populations

Ripe Atlantic herring (Clupea harengus harengus) were sampled from seven discrete spawning grounds in the Gulf of Maine and Gulf of St. Lawrence over a period of 3 yr. Genetic polymorphisms were observed at 13 enzyme loci by starch gel electrophoresis. Five highly polymorphic loci were used to assess population structure of herring stocks by contingency analysis of log-likelihood differences in gene frequencies. Significant temporal variation was observed at several localities. Within both spring spawning and fall spawning populations, significant spatial heterogeneity was noted for particular years, but was not temporally stable. By contrast, overall heterogeneity between spring and fall spawning populations was highly significant indicating genetic isolation of spring spawning populations in the Gulf of St. Lawrence from fall spawning aggregates in the Gulf of St. Lawrence and Gulf of Maine. The low levels of genetic heterogeneity and absence of both temporal stability within fall spawning samples and spatial stability among samples is not consistent with the existence of more than a single genetic population of fall spawning herring in the northwest Atlantic.Key words: Clupea harengus harengus, population genetics, biochemical genetic variation, stock differentiation

Interactions multispécifiques: répartition spatio-temporelle des larves de capelan (Mallotus villosus), d'éperlan (Osmerus mordax) et de hareng de l'Atlantique (Clupea harengus harengus) an sein de la communauté planctonique de l'estuaire moyen du Saint-Laurent

The study of the spatial and temporal organization of the planktonic community of the middle estuary of the Saint Lawrence River revealed that fish larvae were distributed in such a way as to minimize interactions between species. Smelt (Osmerus mordax) larvae were distributed upstream whereas capelin (Mallotus villosus) and Atlantic herring (Clupea harengus harengus) larvae were found downstream in June 1979. Capelin larvae were more abundant at the surface (0–20 m) whereas herring larvae were concentrated in deeper waters (20–60 m). The ecological separation observed was maintained by multiple physical factors and appeared to be the consequence of species-specific reproductive strategies. The abundance of chaetognaths, euphausiids, and amphipods in deeper waters suggests that these forms could be important predators of fish larvae. Herring larvae may be particularly vulnerable because of their distribution in deep water. Capelin larvae which are very abundant in June could also be vulnerable to predation during the diurnal migrations of the macroplankton. Smelt larvae appear to be little affected by predation from these forms as a result of their distribution in fresher waters.

Growth Patterns in a Newfoundland Atlantic Herring (Clupea harengus harengus) Stock

Growth patterns in a discrete Atlantic herring (Clupea harengus harengus) stock were examined using back-calculated lengths derived from otolith measurements and empirical data. The influence of abiotic and biotic factors on growth was examined and evaluated for possible density-dependent or density-independent effects. The results give little evidence to support density-dependent herring growth in the 1st year, but suggest density-independent growth regulated by temperature. A growth compensation mechanism appears to occur in subsequent years resulting in a stable maturation pattern within the stock.Key words: herring, growth, density-dependent, density-independent, growth compensation, maturation

Production Responses for Multi-species Fisheries

Production equations are estimated for five major species of fish harvested in the Northwest Atlantic including Atlantic cod (Gadus morhua), haddock (Melanogrammus aeglefinus), flounder (Pleuronectiformes), redfish (Sebastes marinus), and herring (Clupea harengus) using data collected by the International Commission for the Northeast Atlantic Fisheries from 1960 to 1974. A log-linear regression specification is used in which the relationship between catch of a vessel and several factors including days fished and vessel characteristics is estimated simultaneously. Vessel characteristics are represented as (0, 1) categorical variables, and include a variable indicating the target species designated by the caption. Various settings for the target species variables allow the estimated equation to represent either a by-catch or target catch equation. The production parameters estimated by the regressions are used to analyze the effects of current quotas set by the New England Fisheries Management Council. For some fleets we find a likelihood of idle capacity given the current quotas.Key words: fisheries economics, multi-species harvesting, Northwest Atlantic fisheries

Di-n-hexyl Phthalate (DHP), a Newly Identified Contaminant in Atlantic Herring (Clupea harengus harengus) and Atlantic Mackerel (Scomber scombrus)

We describe the isolation and identification of di-n-hexyl phthalate, a new marine pollutant found in Atlantic herring (Clupea harengus harengus) and Atlantic mackerel (Scomber scombrus). This compound was isolated from extracted lipids by a combination of gel permeation, high performance liquid and column chromatography, and selective precipitation of impurities. Conclusive proof of its structure was obtained from gas chromatographic–mass spectrometric analysis and proton nuclear magnetic resonance spectroscopy. The concentrations of di-n-hexyl phthalate (17–27 μg/g wet weight), which is not a major industrial phthalic acid ester, far exceeded those of dibutyl and di-2-ethylhexyl phthalates, the major industrial phthalic acid esters. Thus the possibility of selective bioaccumulation of DHP in herring and mackerel was indicated. This finding is important in view of the paucity of toxicological information concerning this compound.Key words: phthalic acid ester, di-n-hexyl phthalate (DHP), analysis, mackerel, herring, marine fish, pollution

The effect of rapid changes of hydrostatic pressure on the Atlantic herring Clupea harengus L. I. Larval survival and behaviour

Larval Atlantic herring ( Clupea harengus L.) from 11–39 mm total body length were subjected to different series of pressure changes intended to simulate passage through the cooling water of a thermal power station. This involved both acclimation and rapid pressure increases to 5 atmospheres pressure, followed by rapid decompression. Subsequent mortality, feeding and depth-compensating behaviour were checked as well as the integrity of the gas-filled auditory bulla-swimbladder system which develops between 23–35 mm. There was no evidence of increases in mortality in larvae up to about 20 mm. Larvae from about 25–29 mm showed increased mortality over controls; still larger larvae did not. Larvae which survived the pressure treatment fed as well as controls. There was strong evidence that larvae of all ages attempted to compensate for pressure changes by making appropriate vertical swimming movements. Some of the mortality of the intermediate-sized larvae may be attributed to hyperactivity in a restricted (experimental) space. The bulla membrane in some older larvae was ruptured by the pressure changes. Although this was not immediately a cause of mortality, it would impair mechanical reception in the long term.

The effect of rapid changes of hydrostatic pressure on the Atlantic herring Clupea harengus L. II. The response of the auditory bulla system in larvae and juveniles

Rupturing of the pro-otic membrane of the Atlantic herring ( Clupea harengus L.) occurs if the hydrostatic pressure is rapidly increased from 1 to 3 aim in 12 15 cm long fish. Smaller juveniles and larvae arc much less at risk. The effects of pressure depend on an adapting mechanism which involves the development of the swimbladder at a length of 30–35 mm. The swimbladder acts as a reservoir or sink of gas for the bulla. The time constants for this adaptation can be measured by observations of the external lateral recess membrane in the intact fïsh or the internal bulla membrane in intact transparent larvae or dissected older fïsh. The time constant is of the order of 0.3–1.75 min depending on which membrane is observed, whether the pressure is increased or decreased and whether the system has been ‘in use’ or not. This has an implication for entrainmcnt of the smaller stages which can pass the screens of power station intakes and for ‘acceptable’ depth ranges and rates of vertical migration for all stages.

Chemical and Sensory Analysis of Ungutted Offshore (Nonspawning) Capelin (Mallotus villosus) Stored in Ice

Based on changes in chemical and sensory variables, the keeping time of ungutted offshore capelin (Mallotus villosus) stored in ice was ~ 12 d, which was superior to other pelagic fish such as inshore (spawning) male capelin, Atlantic herring (Clupea harengus harengus) and Atlantic mackerel (Scomber scombrus). Free fatty acid, hypoxanthine, trimethylamine, and moisture content as well as iodine number and muscle pH significantly (P ≤ 0.05) changed during 16 d of iced storage. Although changes in lipid content and peroxide value were statistically significant (P ≤ 0.05), it is questionable whether these changes were chemically significant. Hypoxanthine and trimethylamine appeared to have the most potential for use as indices of sensory quality deterioration during iced storage. Key words: capelin, flavor, free fatty acids (FFA), hypoxanthine, iced storage, odor, overall acceptability, peroxide value, texture, trimethylamine (TMA)

Migrations and Activity Levels of Overwintering Atlantic Herring (Clupea harengus harengus) along Southwest Newfoundland

Recoveries of tagged Atlantic herring (Clupea harengus harengus) released with abdominally inserted magnetic tags indicated a rapid and random dispersion of tagged fish within the total population of herring along southwest Newfoundland. Recoveries further indicated a general westward movement of herring along southwestern Newfoundland from January to March, also reflected in the spatial distribution of commercial catches during this period. Metabolic rates of these overwintering herring, estimated from changes in body energy from December to March, were more than double the standard level, suggesting a high degree of activity, possibly due to avoidance behavior in relation to predatory actions by cod overwintering in the same area. Key words: tagging, movements, predation, metabolic levels

Healing of Wounds and Location of Tags in Atlantic Herring (Clupea harengus harengus) Released with Abdominally Inserted Magnetic Tags

Information derived from Atlantic herring (Clupea harengus harengus) released with abdominally inserted magnetic tags and recovered by an electronic tag-detection system indicated that sustained mortality due to internal damage caused by the tag or the incision wound was probably minimal. In addition, tags that have not become attached to the body wall and internal organs prior to spawning will to a large degree be extruded with the gonadal products during spawning. Key words: tagging, wounding, mortality

Dinoflagellate Toxins as Probable Cause of an Atlantic Herring (Clupea harengus harengus) Kill, and Pteropods as Apparent Vector

Stomachs of Atlantic herring (Clupea harengus harengus) from a kill that occurred in the Bay of Fundy during a bloom of the toxic dinoflagellate Gonyaulax excavata contained pteropods, algal remains, and paralytic toxins. Experiments show that comparable amounts of G. excavata toxins can kill herring rapidly. It is likely that the kill was caused by paralytic dinoflagellate toxins, and that the pteropod Limacina retroversa, a planktonic herbivore, acted as a vector of the toxins. Key words: Dinoflagellate toxins, Gonyaulax excavata, herring kill, Clupea harengus harengus, pteropod, Limacina retroversa

Estimates of Tag Extrusion and Initial Tagging Mortality in Atlantic Herring (Clupea harengus harengus) Released with Abdominally Inserted Magnetic Tags

Returns of Atlantic herring (Clupea harengus harengus) tagged internally with magnetic tags along southwest Newfoundland and in the southern Gulf of St. Lawrence in 1970–71 were analyzed for biases due to initial tagging mortality and to tag extrusion during the reproductive act. Initial tagging mortalities calculated by two methods ranged from 4 to 49% and increased with the duration of impoundment of the fish prior to tagging. Estimates of tag loss during the spawning season indicated that most of the tags inserted in ripening herring were extruded with the reproductive products, whereas those applied to recently spent or recovering herring had sufficient time to become attached to internal organs and hence had a high retention rate. The results indicate that the effectiveness of tagging herring internally will be greatly improved if conducted on recovering or spent fish impounded for only short periods of time before tagging.

Variations in Fillet Lipid Content and Some Percent Lipid-Iodine Value Relationships for Large Winter Atlantic Herring (Clupea harengus harengus) from Southeastern Newfoundland

Lipid was extracted from fillets of large Newfoundland winter Atlantic herring (Clupea harengus harengus) gillnetted in Placentia Bay. In the period January through March percent lipid fell more sharply in females than in males, but lipid-iodine values declined at approximately the same rates. Lipid-iodine values were noticeably higher (about 20 units, maximum values ca. 160) than for the oils produced from fish seined in adjacent waters and commercially reduced. It is proposed that these particular herring are an isolated stock peculiar to Placentia Bay, but that they show certain aspects of lipid biochemistry that are influenced by the reproductive cycle in common with other herring from the Atlantic and Pacific oceans.

Tocopherol Composition of Frozen Atlantic Herring (Clupea harengus harengus) Tissues and Oil

The concentrations of tocopherols in frozen stored Atlantic herring (Clupea harengus harengus) tissues were examined and found to vary with tissue type and the reproductive state of the fish. Only oc-tocopherol was found to be present in herring muscle and oil.

Delineating Spring and Autumn Herring Populations in the Southern Gulf of St. Lawrence by Discriminant Function Analysis

A discriminant function based on three variables, pectoral and dorsal fin rays and gill rakers, was calculated for Atlantic herring (Clupea harengus harengus) taken from spring- and autumn-spawning concentrations in the southern Gulf of St. Lawrence and tested for general applicability by classifying other herring of known origin. The function was then used to classify herring sampled from feeding concentrations. Results showed that feeding herring (pre- and postspawning) comprised a mixture of spring and autumn herring populations averaging 51.8 and 48.2%, respectively.The observed heterogeneity of feeding concentrations, in contrast to homogeneity of spawning concentrations, confirmed the hypothesis that spring and autumn herring populations mix during feeding, though they separate at the onset of spawning. Discriminant function analysis is most useful for separating herring spawning groups during their feeding season when overlap of maturation stages prevents separation by maturation stage alone.