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

1982 ◽  
Vol 39 (12) ◽  
pp. 1610-1621 ◽  
Author(s):  
Irv Kornfield ◽  
Bruce D. Sidell ◽  
P. S. Gagnon

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

1985 ◽  
Vol 42 (S1) ◽  
pp. s158-s173 ◽  
Author(s):  
V. C. Anthony ◽  
M. J. Fogarty

Atlantic herring (Clupea harengus harengus) recruitment in the Gulf of Maine since 1947 has varied by a ratio of 20 to 1. Since heavy fishing began in the mid-1960's, recruitment has fluctuated by only a factor of 9 to 1. The greatest fluctuations in recruitment, therefore, historically occurred in the absence of high fishing mortality. Recruitment predictions and understanding of the causes of fluctuations are extremely important, since strong year classes traditionally have sustained the herring fisheries in the Gulf of Maine. The effect of environmental variables (particularly temperature) on herring recruitment and growth were examined in detail. Vulnerability of Gulf of Maine herring in response to moon phase is also considered. Indices of abundance of Atlantic herring in the Gulf of Maine were calculated for three time periods using three different procedures. Indices of abundance for the periods of 1915–67 and 1951–81 indicated that productivity, or amount of recruitment per amount of spawning stock, was positively related to temperature or other factors (e.g. food availability) related to temperature at intermediate to high levels of spawning stock biomass. For the shorter and most recent time period (1965–81), abundance was calculated by virtual population analysis and an attempt was made to relate temperature effects during several periods in the first year of life to recruitment levels at age 2. The mean, maximum, and minimum water temperatures during (1) September–December (spawning – early larval development), (2) January–April (overwintering and late larval development), and (3) May–August (postlarval) periods were correlated with abundance. Significant effects of mean and minimum temperature during period 2 and minimum temperature during period 3 were observed, suggesting that environmental influences on determination of year class strength occur during late larval – early juvenile phases. Possible reasons for the discrepancy between the long-term analyses bases on abundance indices and the more detailed analyses using population size estimates based on virtual population analysis are discussed. An indication of environmental limitation is also shown by density-dependent growth. Growth appears to be related to both age 2 abundance and summer water temperature. When abundance is great, its effect overcomes the positive effect of temperature (or other factors indicated by temperature). The environment also alters the availability and vulnerability of herring to the inshore fisheries. Young herring are more available and vulnerable to fixed gear during the dark phase of the moon. This effect is pronounced when abundance is low.


1966 ◽  
Vol 44 (10) ◽  
pp. 1319-1326 ◽  
Author(s):  
Paul H. Odense ◽  
Theresa M. Allen ◽  
Ted C. Leung

The distribution of isoenzymes of lactate dehydrogenase (LDH) and aspartate aminotransferase (AAT) in the tissues of 189 herring (Clupea harengus harengus L.) were examined. Starch-gel electrophoresis of the LDH isoenzymes of the herring revealed the presence of two hybrid forms representing mutant alleles at the B locus. These mutants gave rise to two genotypes, BB′ and BB″, whose LDH staining patterns revealed a binomial distribution of the tetramer combinations formed from a free and random association of the A, B, and B′, and the A, B, and B″ monomers respectively.A hybrid form of soluble AAT was found. Its electrophoretic pattern showed a 1:2:1 binomial distribution of bands. It is postulated that these bands represent AAT dimers formed from normal S and mutant S′ monomers of a heterozygous SS′ genotype. The normal homozygous SS genotype showed only one band of activity.The normal levels of LDH and AAT activity in plasma and in heart and skeletal muscles were determined. During frozen storage LDH-5 activity gradually disappeared, while LDH-1 activity changed least; LDH-1 was also most stable at higher temperatures. Frozen storage rapidly destroyed AAT activity.


1985 ◽  
Vol 42 (5) ◽  
pp. 989-998 ◽  
Author(s):  
G. H. Winters ◽  
J. P. Wheeler

The relationship between commercial catch-rates and population density upon which many stock assessment models depend assumes that stock area (A) is constant and independent of population abundance. Starting from a theoretical demonstration that the catchability coefficient (q) is inversely proportional to A, we establish the empirical basis of this relationship through comparisons of q and A of various Northwest Atlantic herring (Clupea harengus harengus) stocks and, in more detail, for Fortune Bay herring. For these stocks the relationship was of the form q = cA−b. For Atlantic herring stocks, levels of b were in excess of 0.80. In Fortune Bay herring, reductions in abundance were accompanied by proportional reductions in A, which in turn was inversely correlated with changes in q. School size, measured as catch per set, also declined as population levels declined but the change was not proportional. Published findings indicate that pelagic stocks in particular, and fish stocks in general, exhibit a common response of reductions in A with interactive increases in the q during periods of rapid population decline. We conclude that the conventional assumption of a constant stock area is usually violated due to the systematic interaction between A and population abundance which is reflected in an inverse relationship between stock abundance and q. Calibration of sequential population models should therefore be restricted to research vessel data collected in a standard manner and covering the distributional area of the stock.


1978 ◽  
Vol 35 (1) ◽  
pp. 148-154 ◽  
Author(s):  
Paul W. Reno ◽  
Marie Philippon-Fried ◽  
Bruce L. Nicholson ◽  
Stuart W. Sherburne

Erythrocytes of PEN-positive Atlantic herring (Clupea harengus harengus) were examined to determine their ultrastructure. Cytoplasmic inclusions were of two types when observed under the electron microscope. The first type (type I) appeared coarsely granular, electron dense, round, and up to 1.5 μm in diameter. Virions were closely associated with this type of inclusion. The second type of inclusion (type II) had approximately the same appearance as the surrounding cytoplasm, from which it was separated by a discrete membrane, and was variable in size. Virions were not intimately associated with type II inclusions. Virions occurred singly or in clusters within the cytoplasm or in association with type I inclusions and were hexagonal and 145 nm in diameter. Virions were composed of a rigid hexagonal capsid 8 nm wide, a lighter 16-nm region, and a core 100 nm in diameter. The virus of PEN is presumptively classified as an Iridovirus. Key words: ultrastructure, erythrocytes, virology


1964 ◽  
Vol 6 (1) ◽  
pp. 107-117 ◽  
Author(s):  
G. A. E. Gall ◽  
R. T. Berg

SUMMARY1. The transferrins in two cattle herds were studied by means of starch gel electrophoresis. Three phenotypes were observed in a Hereford herd and six in a Hybrid herd comprised of Galloway, Aberdeen Angus and Charolais breeds.2. Gene frequencies were calculated for each herd. Great variation was found in the frequency of the transferrin alleles between breed and source within the Hybrid herd and between the Hybrid and Hereford herds. The frequencies of the transferrin alleles found in the cows in the Hereford herd were TfA = 0·467 and TfD = 0·533; those found in the cows in the Hybrid herd were TfA = 0·382, TfD = 0·506 and TfE = 0·112.3. Progeny data were in general agreement with the three-allele theory of inheritance, although the data suggested that offspring in the Hybrid herd carrying the TfE allele occurred at a lower frequency than expected.4. The possible relation of transferrin type to embryonic mortality was studied. The results were in general agreement with those of other workers, indicating a possible interaction between the genotypes of the foetus and dam.5. The characteristics of the transferrin types and the postulated three-allele genetic mechanism for the control of the observed variation are discussed.


1990 ◽  
Vol 47 (3) ◽  
pp. 460-470 ◽  
Author(s):  
G. H. Winters ◽  
J. P. Wheeler

Length-specific selection curves for Atlantic herring (Clupea harengus) were calculated for a series of gillnets ranging in mesh size from 50.8 to 76.2 mm (stretched measure) using Holt's (1963) model (ICNAF Spec. Publ. 5: 106–115). These curves were than compared with direct estimates of length-specific selectivity obtained from a comparison of gillnet catch length frequencies with population length composition data as determined from acoustic surveys. Selection curves calculated indirectly using the Holt model were unimodal and congruent. The empirical selection curves however were multimodal and fishing power varied with mesh size. These differences in selectivities were due to the fact that herring were caught not only by wedging at the maximum girth but also at other body positions such as the gills and snout. Each of these modes of capture have different length-specific selectivity characteristics and, since the relative contributions of the different modes of capture varied both between nets and annually, the selection curve of herring for a particular mesh size is not unique. It can however be reasonably approximated when girth is used as the selection criterion. Direct empirical selectivities are therefore recommended when interpreting population parameters from herring gillnet catch data.


1987 ◽  
Vol 44 (7) ◽  
pp. 1379-1385 ◽  
Author(s):  
Sharon E. McGladdery

Prevalence of Eimeria sardinae oocysts was closely correlated with the maturity stage of the testes of Atlantic herring (Clupea harengus harengus). Prevalence was low in testes of immature fish, increased in ripe and spawning fish, and decreased in postspawning fish. No correlation was found between prevalence and age of spawning herring. The uniformly high prevalences in mature fish indicated the efficiency of transmission on the spawning grounds, where infective oocysts are released. Infection of first-spawning herring (approximately age 3) indicated that the oocysts may be dispersed to surrounding areas or immature fish may associate with spawning aggregations. Therefore, this parasite could not be used to distinguish first from repeat spawners. Prevalence oF E. sardinae peaked in May and September, and possibly in June and early July, thereby distinguishing two, and possibly three, spawning groups. A previous study indicated no correlation between maturity stage and infections by E. sardinae in northeastern Atlantic herring. The difference between the two sides of the Atlantic is attributed to greater mixing of immature and adult herring around spawning grounds and/or greater dispersal of infective oocysts from spawning grounds in the northeastern Atlantic, compared with those in the northwest.


2014 ◽  
Vol 30 (3) ◽  
pp. 377-390 ◽  
Author(s):  
S.S.A. Egena ◽  
R.O. Alao

Biochemical diversity or polymorphism is the occurrence of varieties attributed to biochemical differences which are under genetic control. It has created a leeway for the genetic improvement of farm animals. This is because it can be used as a useful tool for the characterization of livestock breeds and population. This way, the degree of similarity or differences within and between breeds can be ascertained and this differences or similarity are important raw materials for genetic improvement of animals. Data obtained on gene frequencies and genotypes through polymorphism study makes it not only possible to compare the gene stocks of animals, the possible effects of the genes on reproductive and performance traits, but also study genetic variability under different environmental conditions of selection. This study was carried out to review haemoglobin (Hb) polymorphism in selected farm animals with the view of finding out the type of polymorphism observed by starch gel electrophoresis due to variation in the amino acid sequence in the polypeptide chains of Hb. The review showed clearly that there is a gene-controlled diversity in the different farm animals considered. This could serve as a reference point for future studies earmarked for the improvement of the animals possibly via marker-assisted selection.


1990 ◽  
Vol 68 (8) ◽  
pp. 1652-1658 ◽  
Author(s):  
K. Vanya Ewart ◽  
Garth L. Fletcher

Antifreeze proteins (AFPs) from smelt (Osmerus mordax) and Atlantic herring (Clupea harengus harengus) were isolated using gel filtration, ion exchange chromatography, and high performance liquid chromatography. The AFPs of smelt appeared to consist of at least six components and those of Atlantic herring, of at least two components. The relative molecular masses of these antifreezes were 24 000 and 14 600, respectively. Amino acid analysis showed both proteins to be cystine-rich, type II AFPs like those of the sea raven (Hemitripterus americanus). In addition, smelt AFPs were found to be immunologically similar to those of the sea raven. The smelt AFPs differed from those of Atlantic herring and sea raven in that they contained a small amount of glucosamine (~3%). The activity levels of the smelt and herring AFPs were reduced in the presence of dithiothreitol, indicating the functional importance of intact disulfide bonds.


1975 ◽  
Vol 32 (1) ◽  
pp. 66-68 ◽  
Author(s):  
S. N. Messieh

Analysis of maturity stages of herring samples taken from the southern Gulf of St. Lawrence shows two maturation cycles for spring and autumn spawning herring. The spring population has a spawning peak in May and the summer–autumn population extends spawning from July through September. Spawning grounds of spring and autumn herring populations and their nursery areas are mapped.


Sign in / Sign up

Export Citation Format

Share Document