The use of historical catch data to trace the influence of climate on fish populations: examples from the White and Barents Sea fisheries in the 17th and 18th centuries

Abstract We analysed catch records of Atlantic salmon (Salmo salar), cod (Gadus morhua), and halibut (Hippoglossus hippoglossus and Reinhardtius hippoglossoides) from the 17th and 18th centuries from several locations of the Barents and White Seas areas. Historical records, found in Russian archives, allow analysis of long-term series of catches, and sometimes of the average weight of the fish. In total, we obtained data on catches of salmon for 51 years (for the period from 1615 to 1772) and of cod and halibut for 33 years (for the period from 1710 to 1793). These data are comparable with respect to fishing effort within the series. The data on Atlantic salmon are also comparable with statistical data for the period 1875–1915. We found notable fluctuations in catches and sometimes in the average weight of salmon. There was also fluctuation in catches of cod and halibut. Both observational comparison of catch series and temperature data and formal statistical analysis showed that catches tended to decrease during relatively colder periods.

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Barents Sea cod (Gadus morhua) diet composition: long-term interannual, seasonal, and ontogenetic patterns

ICES Journal of Marine Science ◽

10.1093/icesjms/fsz117 ◽

2019 ◽

Vol 76 (6) ◽

pp. 1936-1936 ◽

Cited By ~ 1

Author(s):

Rebecca E Holt ◽

Bjarte Bogstad ◽

Joël M Durant ◽

Andrey V Dolgov ◽

Geir Ottersen

Keyword(s):

Diet Composition ◽

Gadus Morhua ◽

Barents Sea

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Population Dynamics of the Arcto-Norwegian Cod

Journal of the Fisheries Research Board of Canada ◽

10.1139/f67-012 ◽

1967 ◽

Vol 24 (1) ◽

pp. 145-190 ◽

Cited By ~ 24

Author(s):

D. J. Garrod

Keyword(s):

Gadus Morhua ◽

Barents Sea ◽

Fishing Effort ◽

Catch Per Unit Effort ◽

Group Iii ◽

Spawning Stock ◽

Stock Recruitment ◽

Post War ◽

The One ◽

Definition Of

By reason of its geographical distribution, the Arcto-Norwegian cod (Gadus morhua) supports three distinct fisheries, two feeding fisheries in the Barents Sea and at Bear Island–Spitsbergen, and a spawning fishery off the Norway coast. In the past this diversity of fishing on the one stock has made it difficult to unify all the data to give an overall description of post-war changes in the stock. In this contribution three modifications of conventional procedures are introduced which enable this to be done. These are: (i) a system of weighting the catch per unit effort data from each fishery to a level of comparability; (ii) a more rigorous definition of the effective fishing effort on each age-group; (iii) a method of estimation of the effective fishing effort on partially recruited age-groups.Using these methods the analysis presents the effects of fishing on each fishery in the context of its effect on the total stock, and at the same time it indicates ways in which factors other than fishing may have influenced the apparent abundance of the stock. The treatment of the data is also used to derive estimates of spawning stock and recruitment of 3-year-old cod for subsequent analysis of stock–recruitment relationships.

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Deriving condition indices from standard fisheries databases and evaluating their sensitivity to variation in stored energy reserves

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f04-128 ◽

2004 ◽

Vol 61 (10) ◽

pp. 1900-1917 ◽

Cited By ~ 34

Author(s):

C Tara Marshall ◽

Coby L Needle ◽

Nathalia A Yaragina ◽

Adnan M Ajiad ◽

Evgeny Gusev

Keyword(s):

Body Size ◽

Gadus Morhua ◽

Barents Sea ◽

Condition Index ◽

Energy Reserves ◽

Stored Energy ◽

Stock Level ◽

Length Relationship ◽

Condition Indices

To evaluate interstock differences in condition, it would be advantageous to develop stock-level condition indices from standardized databases on weight and length. This study describes a method for estimating stock-level condition when individual-level observations on length and weight are not easily accessible. For each year in a 56-year time series (19462001) for Northeast Arctic cod (Gadus morhua), pseudo-observations of weight and length were generated by pairing the Norwegian and Russian values for weight-at-age provided annually to the assessment working group with estimates of length-at-age derived from the same databases. A weightlength relationship fit to each year was then used to predict weight-at-length, i.e., girth, for a range of standard lengths (30120 cm). This index was uncorrelated with both the liver condition index and the abundance of Barents Sea capelin (Mallotus villosus), suggesting that at the stock level, the girth of cod is not necessarily indicative of the magnitude of stored energy reserves. Partitioning body size into length-at-age and girth revealed long-term trends in body size. In particular, large/old cod showed substantially higher values of both length-at-age and girth that could be the result of long-term increases in fishing mortality.

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The code of the long-term biomass cycles in the Barents Sea

ICES Journal of Marine Science ◽

10.1016/s1054-3139(03)00152-8 ◽

2003 ◽

Vol 60 (6) ◽

pp. 1251-1264 ◽

Cited By ~ 10

Author(s):

Harald Yndestad

Keyword(s):

Gadus Morhua ◽

Barents Sea ◽

Temperature Cycle ◽

Biomass Growth ◽

Sea Temperature ◽

Arctic Cod ◽

Temperature Cycles ◽

Large Fluctuations ◽

Capelin Mallotus Villosus

Abstract Barents Sea capelin (Mallotus villosus), Norwegian spring-spawning herring (Cluea harengus), and Northeast Arctic cod (Gadus morhua) have been associated with large fluctuations of biomass growth. The cause of these large fluctuations has been poorly understood and led to problems in biomass management. The identification of a deterministic cause would provide the possibility of forecasting future biomass fluctuations. In this investigation, the Kola Section sea temperature and the biomasses of capelin, herring, and cod have been analyzed by a wavelet transform to identify the source of the long-term cycles. The wavelet analysis shows that the Kola Section temperature has dominant cycles at the lunar-nodal tide cycles of 3×18.6=55.8, 18.5 and 18.6/3 = 6.2 years. The recruitment of Barents Sea capelin, Norwegian spring-spawning herring, and Northeast Arctic cod has adopted an optimal recruitment cycle close to the stationary 6.2 years Kola temperature cycle. Long-term biomass growth is correlated to the phase relation between the biomass eigen-frequency cycle and the Kola temperature cycles. The biomasses of capelin, herring and cod have long-term growth when the 6.2 and 18.6 years Kola temperature cycles are positive at the same time. There is a long-term biomass reduction when the temperature cycles are not positive at the same time, and a biomass collapse when the temperature cycles are negative at the same time. The deterministic property of the 18.6 years lunar-nodal tide provides a new way of long-term biomass forecasting over periods of 50–80 years or more.

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Economic impacts of changes in the population dynamics of fish on the fisheries of the Barents Sea

ICES Journal of Marine Science ◽

10.1016/j.icesjms.2006.01.003 ◽

2006 ◽

Vol 63 (4) ◽

pp. 611-625 ◽

Cited By ~ 9

Author(s):

P. Michael Link ◽

Richard S.J. Tol

Keyword(s):

Population Dynamics ◽

Fish Species ◽

Gadus Morhua ◽

Barents Sea ◽

Short Term ◽

Fishing Activity ◽

The Barents Sea ◽

Capelin Mallotus Villosus ◽

Long Term Impact

Abstract A bioeconomic simulation model of the two interacting fish species cod (Gadus morhua) and capelin (Mallotus villosus) and their fisheries is presented and applied to assess the consequences of changes in the population dynamics of these important fish stocks in the Barents Sea. In each scenario, the population dynamics of the fish species are changed by reducing the reproduction-induced productivities and/or the carrying capacities. Stock sizes and landings of fish are calculated for each fishing period, and the net present values of profits from fishing are determined for time periods prior to and after the change in population dynamics. Results show that reduced growth rates or carrying capacities lead to lower stock levels and consequently to smaller catches. There is only a small short-term economic impact on the fisheries, but the long-term consequences are pronounced. In some cases, greater fishing activity in the first few years after the change in population dynamics causes harvests to remain stable despite diminishing stock sizes. This stabilizes the returns from fishing in the short term, but veils the apparent negative long-term impact on the fisheries resulting from adversely affected stock dynamics.

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Evolution in salmon life-history induced by direct and indirect effects of fishing

10.1101/2021.01.08.425869 ◽

2021 ◽

Author(s):

Yann Czorlich ◽

Tutku Aykanat ◽

Jaakko Erkinaro ◽

Panu Orell ◽

Craig R Primmer

Keyword(s):

Atlantic Salmon ◽

Prey Species ◽

Barents Sea ◽

Fishing Effort ◽

Age At Maturity ◽

Anthropogenic Pressures ◽

Sea Temperature ◽

Early Maturation ◽

Commercial Harvest ◽

Late Maturation

Understanding the drivers of evolution is a fundamental aim in biology. However, identifying the evolutionary impacts of human activities, both direct and indirect, is challenging because of lack of temporal data and limited knowledge of the genetic basis of most traits1. Atlantic salmon is a species exposed to intense anthropogenic pressures during its anadromous life cycle. Previous research has shown that salmon age at maturity has evolved towards earlier maturation over the last 40 years, with an 18% decrease in the allele associated with late maturation at the large-effect vgll3 locus; but the drivers of this change remain unknown. Here, we link genetic and phenotypic changes in a large Atlantic salmon population with salmon prey species biomass in the Barents Sea, temperature, and fishing effort in order to identify drivers of age at maturity evolution. We show that age at maturity evolution is associated with two different types of fisheries induced evolution acting in opposing directions: an indirect effect linked with commercial harvest of a salmon prey species (capelin) at sea (selection against late maturation), and a direct effect due to temporal changes in net fishing pressure in the river (surprisingly, selection against early maturation). Although the potential for direct and indirect evolutionary effects of fishing have been acknowledged, empirical evidence for induced changes at the genetic level has been lacking. As capelin are primarily harvested to produce fish meal and oil for aquaculture, we hereby identify an indirect path by which Atlantic salmon aquaculture may negatively affect wild populations.

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Anesthesia for rabbits submitted to experimental surgeries: Report of a series of eight anesthesias

Panorama brasileiro de tungstênio (w) entre os anos de 2008 e 2014 ◽

10.32749/nucleodoconhecimento.com.br/health/anesthesia-for-rabbits ◽

2020 ◽

pp. 151-158

Author(s):

Rafael Antonio Caldart Bedin ◽

Maisa Schultz ◽

Antonio Bedin

Keyword(s):

Muscle Relaxation ◽

Anesthetic Management ◽

Laboratory Animals ◽

Average Weight ◽

Anesthetic Induction ◽

Anesthetic Agents ◽

Reasonable Degree ◽

Bioethical Debate ◽

Precordial Stethoscope

Anesthesia for laboratory animals is a matter of biomedical concern and one of the most present dilemmas in the current bioethical debate. The use of anesthetic agents in experimental surgery aims at analgesia and restraining the animal, in order to achieve a reasonable degree of muscle relaxation and to produce sufficient analgesia. This practice requires the use of protocols for the administration of safe and efficient doses. Eight New Zealand rabbits were submitted to laparotomies demonstrating the surgical technique discipline of the local medical course. For pre-anesthetic medication, acepromazine 1 mg.kg-1 associated with ketamine 15 mg.kg-1 was used subcutaneously. Anesthesia was maintained with isoflurane and oxygen under a laryngeal mask in a Mapleson D anesthesia system and under spontaneous breathing. Hydration was performed with 10 ml.kg-1 saline every hour. A thermal mattress was used. Precordial stethoscope, pulse oximetry and clinical parameters were used for monitoring. For euthanasia, ketamine 10 mg.kg-1 associated with potassium chloride 19.1% 1 ml.kg-1 was used intravenously. The average weight of the rabbits was 2721.25 ± 275.01 grams and the duration of the anesthetic procedure was 120 ± 87 minutes. Discussion. In long-term anesthesia, such as laparotomies, the use of pre-anesthetic medication and then anesthetic induction by the combination of agents is recommended. However, anesthetic management requires monitoring to prevent insufficient or excessive doses from occurring.

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Long-term dynamics and destruction of marsh vegetation in the Kolokolkova Bay of the Barents Sea

Vegetation of Russia ◽

10.31111/vegrus/2012.21.66 ◽

2012 ◽

pp. 66-77 ◽

Cited By ~ 4

Author(s):

I. A. Lavrinenko ◽

O. V. Lavrinenko ◽

D. V. Dobrynin

Keyword(s):

Species Composition ◽

Plant Communities ◽

Barents Sea ◽

Mean Value ◽

Marsh Vegetation ◽

Composition And Structure ◽

The Mean ◽

Species Composition And Structure

The satellite images show that the area of marshes in the Kolokolkova bay was notstable during the period from 1973 up to 2011. Until 2010 it varied from 357 to 636 ha. After a severe storm happened on July 24–25, 2010 the total area of marshes was reduced up to 43–50 ha. The mean value of NDVI for studied marshes, reflecting the green biomass, varied from 0.13 to 0.32 before the storm in 2010, after the storm the NDVI decreased to 0.10, in 2011 — 0.03. A comparative analysis of species composition and structure of plant communities described in 2002 and 2011, allowed to evaluate the vegetation changes of marshes of the different topographic levels. They are following: a total destruction of plant communities of the ass. Puccinellietum phryganodis and ass. Caricetum subspathaceae on low and middle marches; increasing role of halophytic species in plant communities of the ass. Caricetum glareosae vic. Calamagrostis deschampsioides subass. typicum on middle marches; some changes in species composition and structure of plant communities of the ass. Caricetum glareosae vic. Calamagrostis deschampsioides subass. festucetosum rubrae on high marches and ass. Parnassio palustris–Salicetum reptantis in transition zone between marches and tundra without changes of their syntaxonomy; a death of moss cover in plant communities of the ass. Caricetum mackenziei var. Warnstorfia exannulata on brackish coastal bogs. The possible reasons of dramatic vegetation dynamics are discussed. The dating of the storm makes it possible to observe the directions and rates of the succession of marches vegetation.

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