Genetic diversity of coastal Northwest Atlantic herring populations: implications for management

Egg weight varies among northwest Atlantic herring (Clupea harengus) populations that spawn in different seasons (n = 12), but the range in weights is less than half of that known for northeast Atlantic populations. Egg weights were similar for both spring (May–June)- and autumn (August–October)-spawning herring (1.06 ×) and most dissimilar between spring- and summer (July)-spawning herring (1.21 ×). Mean population egg weights were not correlated with temperature either at spawning or for the last 2 mo of the egg development period. The product of egg weight and fecundity (standardized to length) differed between spring- and autumn-spawning herring of the southern Gulf of St. Lawrence. Spring-spawners, particularly smaller fish [Formula: see text], have lower ripe ovary weights than do autumn-spawning herring. Differences between spawning seasons in the relative allocation of storage energy to gonad and metabolism, a process mediated by the duration of the gonad maturation period, are the likely basis for the observed patterns.

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Backscatter measurements of Atlantic herring in the Northwest Atlantic

The Journal of the Acoustical Society of America ◽

10.1121/1.4743051 ◽

2000 ◽

Vol 108 (5) ◽

pp. 2457-2457

Author(s):

William L. Michaels ◽

J. Michael Jech ◽

David A. Demer

Keyword(s):

Atlantic Herring ◽

Northwest Atlantic

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Consecutive acoustic observations of an Atlantic herring school in the Northwest Atlantic

ICES Journal of Marine Science ◽

10.1093/icesjms/fsp090 ◽

2009 ◽

Vol 66 (6) ◽

pp. 1270-1277 ◽

Cited By ~ 15

Author(s):

Thomas C. Weber ◽

Héctor Peña ◽

J. Michael Jech

Keyword(s):

Angular Dependence ◽

Clupea Harengus ◽

Atlantic Herring ◽

Georges Bank ◽

Northwest Atlantic ◽

Multibeam Echosounder ◽

Fish School ◽

Catch Data ◽

Trawl Catch ◽

Synoptic Observations

Abstract Weber, T. C., Peña, H., and Jech, J. M. 2009. Consecutive acoustic observations of an Atlantic herring school in the Northwest Atlantic. – ICES Journal of Marine Science, 66: 1270–1277. Several successive images of the same school of Atlantic herring (Clupea harengus) were collected over the course of ∼1 h just north of Georges Bank in the Northwest Atlantic. Although the fish may not have been in their natural, undisturbed state, we observed what appeared to be the fish school fragmenting and dispersing, using a split-beam and a multibeam echosounder. Calibrated, 38 kHz, split-beam echosounder (Simrad EK60) and trawl-catch data provided accurate measures of the fish density beneath the vessel. Uncalibrated, 400 kHz, multibeam-echosounder (Reson 7125) data provided synoptic observations of the fish school including estimates of the school volume, morphology, and behaviour. Observations of the angular dependence in the multibeam-echosounder measurements of backscatter from fish allow investigation of the efficacy of extrapolating fish-school densities measured by the split-beam echosounder to the entire school.

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Genetic Diversity of White Sharks, Carcharodon carcharias, in the Northwest Atlantic and Southern Africa

Journal of Heredity ◽

10.1093/jhered/esv001 ◽

2015 ◽

Vol 106 (3) ◽

pp. 258-265 ◽

Cited By ~ 17

Author(s):

S. J. O'Leary ◽

K. A. Feldheim ◽

A. T. Fields ◽

L. J. Natanson ◽

S. Wintner ◽

...

Keyword(s):

Genetic Diversity ◽

Southern Africa ◽

Carcharodon Carcharias ◽

Northwest Atlantic

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Genetic diversity from pre-bottleneck to recovery in two sympatric pinniped species in the Northwest Atlantic

Conservation Genetics ◽

10.1007/s10592-017-1032-9 ◽

2017 ◽

Vol 19 (3) ◽

pp. 555-569 ◽

Cited By ~ 3

Author(s):

Kristina M. Cammen ◽

Sarah Vincze ◽

A. Sky Heller ◽

Brenna A. McLeod ◽

Stephanie A. Wood ◽

...

Keyword(s):

Genetic Diversity ◽

Northwest Atlantic ◽

Pinniped Species

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Population integrity and connectivity in Northwest Atlantic herring: a review of assumptions and evidence

ICES Journal of Marine Science ◽

10.1093/icesjms/fsp189 ◽

2009 ◽

Vol 66 (8) ◽

pp. 1733-1739 ◽

Cited By ~ 34

Author(s):

Robert L. Stephenson ◽

Gary D. Melvin ◽

Michael J. Power

Keyword(s):

Population Structure ◽

Species Diversity ◽

Spatial Scales ◽

Scientific Evidence ◽

Scientific Information ◽

Ecosystem Approach ◽

Atlantic Herring ◽

Northwest Atlantic ◽

Western Atlantic ◽

Mixed Stock

Abstract Stephenson, R. L., Melvin, G. D., and Power, M. J. 2009. Population integrity and connectivity in Northwest Atlantic herring: a review of assumptions and evidence. – ICES Journal of Marine Science, 66: 1733–1739. The issue of herring population structure has been debated for more than a century. Population integrity and connectivity have become an increasingly important problem for both resource evaluation (e.g. concern for the use of appropriate modelling approaches) and management (e.g. increasing attention to the preservation of within-species diversity and the complexity of mixed-stock fisheries). In recent decades, there has been considerable advancement in the scientific information related to herring population structure, but papers continue to demonstrate a spectrum of conclusions related to population integrity and connectivity at various scales. We review herring stock structure in the western Atlantic, specifically addressing the assumptions currently being used in management and the validity of scientific evidence on which these assumptions are based. Herring of the western Atlantic exhibit considerable population discreteness and limited connectivity on the temporal and spatial scales that are of relevance to management. Maintaining the resulting population complexity is a challenge, particularly because preservation of within-species diversity is an important element of an ecosystem approach to management.

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Length-specific Weight as a Measure of Growth Success of Adult Atlantic Herring (Clupea harengus)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f94-116 ◽

1994 ◽

Vol 51 (5) ◽

pp. 1169-1179 ◽

Cited By ~ 30

Author(s):

G. H. Winters ◽

J. P. Wheeler

Keyword(s):

Specific Weight ◽

Clupea Harengus ◽

Annual Production ◽

Atlantic Herring ◽

Reliable Index ◽

Northwest Atlantic ◽

Surplus Energy ◽

Weak Evidence ◽

Annual Changes ◽

Dependent Growth

We used length-specific weight (i.e., condition) to evaluate growth success of seven stocks of adult Atlantic herring (Clupea harengus) in the Northwest Atlantic. Condition of adult Atlantic herring showed large annual changes as a consequence of abundance-dependent effects. This contradicts the general conclusion that adult herring growth contains little abundance-dependent variation. The published literature, however, is based mainly on traditional growth estimators such as annual length increments which measure only a marginal fraction of annual production whereas condition reflects the seasonal accumulation and depletion of energy and therefore can provide a reliable index of total annual production. We found that annual changes in condition of adult Atlantic herring were only weakly correlated with traditional length-based growth estimates. We concluded that the weak evidence for abundance-dependent growth of adult herring in the literature is a consequence of inappropriate growth estimators. The implication of this finding is that the acquisition of surplus energy by herring can be abundance dependent whereas annual increases in length may not.

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Population structure in Arctic marine forests is shaped by diverse recolonisation pathways and far northern glacial refugia

10.1101/2020.03.19.999466 ◽

2020 ◽

Author(s):

Trevor T. Bringloe ◽

Heroen Verbruggen ◽

Gary W. Saunders

Keyword(s):

Genetic Diversity ◽

Last Glacial Maximum ◽

Bering Sea ◽

Canadian Arctic ◽

Species Distributions ◽

Northwest Atlantic ◽

Last Glacial ◽

The Last Glacial Maximum ◽

The Bering Sea ◽

The Last Glacial

AbstractThe Arctic is experiencing a rapid shift towards warmer regimes, calling for a need to understand levels of biodiversity and ecosystem responses to climate cycles. This study examines marine refugial locations during the Last Glacial Maximum in order to link recolonization pathways to patterns of genetic diversity in Arctic marine forests. We present genetic data for 109 species of seaweed to infer community-level patterns, and hindcast species distributions during the Last Glacial Maximum to further pinpoint likely refugial locations. Sequence data revealed contiguous populations extending from the Bering Sea to the Northwest Atlantic, with high levels of genetic diversity in the East Canadian Arctic. One fifth of the species sampled appeared restricted to Arctic waters. Hindcasted species distributions highlighted refugia in the Bering Sea, Northwest Atlantic, South Greenland, and Europe. We hypothesize that Arctic coastal systems were recolonized from many geographically disparate refugia leading to enriched diversity levels in the East Canadian Arctic, with important contributions stemming from northerly refugia likely centered along Southern Greenland. Moreover, we hypothesize these northerly refugia likely played a key role in promoting polar endemic diversity, as reflected by abundant unique population haplotypes and endemic species in the East Arctic.Significance StatementOur work challenges the existing paradigm that marine Arctic ecosystems are depauperate extensions of southerly (temperate) communities established in the wake of recent glaciation, fundamentally changing how these systems should be viewed and interpreted. We forward novel hypotheses regarding the recent history of Arctic marine systems, particularly with regards to endemism being an integral feature of Arctic biomes, and present a firm framework for future evolutionary research in this system typically viewed as “ecologically immature.”

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