Reproductive patterns of harpacticoid copepods on intertidal macroalgae (Ascophyllum nodosum and Fucus vesiculosus) in Nova Scotia, Canada

1987 ◽  
Vol 65 (1) ◽  
pp. 129-141 ◽  
Author(s):  
S. C. Johnson ◽  
R. E. Scheibling
Keyword(s):  
Seasonal Variation ◽  
Sex Ratio ◽  
Rocky Shore ◽  
Seasonal Fluctuation ◽  
Reproductive Activity ◽  
Ascophyllum Nodosum ◽  
Fucus Vesiculosus ◽  
Reproductive Patterns ◽  
Harpacticoid Copepods ◽  
Continuous Reproduction

Harpacticoid copepods generally showed marked seasonal variation in abundance on intertidal macroalgae (Ascophyllum nodosum, Fucus vesiculosus) on a moderately exposed rocky shore. In some species (Nitocra typica, Mesochra spp., Harpacticus sp., Heterolaophonte spp.) the sex ratio was unbiased, or biased towards males, at peak population densities in summer and fall, but became biased towards females as density decreased towards winter. In other species (Thalestris purpurea, Parastenhelia spinosa, Amphiascopsis sp.) there was no consistent trend in sex ratio. Most species have a protracted period of reproductive activity between spring and fall, as indicated by the occurrence of ovigerous females and copepodites. Some species (Harpacticus sp., Heterolaophonte discophora, Thalestris purpurea) that were absent from macroalgae during winter reappeared with ovigerous females and copepodites in the spring. Tisbe spp. showed no seasonal fluctuation in abundance or sex ratio: ovigerous females and copepodites occurred throughout the year, suggesting continuous reproduction. Reproductive patterns of harpacticoid species on intertidal macroalgae may be related to seasonal variation in temperature and food supply.

SEASONAL VARIATION IN THE CHEMICAL COMPOSITION OF THE FUGACEAE IN THE MARITIME PROVINCES

1952 ◽  
Vol 30 (1) ◽  
pp. 67-77 ◽  
Author(s):  
Margaret G. Macpherson ◽  
E. Gordon Young
Keyword(s):  
Seasonal Variation ◽  
Chemical Composition ◽  
Organic Nitrogen ◽  
Ascophyllum Nodosum ◽  
Fucus Vesiculosus ◽  
Ash Content ◽  
Essential Difference ◽  
Maritime Provinces ◽  
Mineral Salts

Fucus vesiculosus, F. evanescens, and Ascophyllum nodosum have been analyzed monthly for their content of moisture, mineral salts, organic nitrogen, mannitol, laminarin, and alginate over a period of two years. Plants were collected from two localities, St. Andrews, N.B., and Halifax, N.S. In general, when the ash content was at a minimum in the winter months, alginate was at a maximum. The converse was true in spring and summer. Organic nitrogen and laminarin remained relatively constant throughout the year. Mannitol was highest in the summer and autumn, fluctuating with the temperature of the water. No essential difference was detected between the results of St. Andrews and at Halifax, or between the three species examined. Analyses carried out on samples collected at different times on the same day showed no significant differences.

Responses of three sympatric snake species to tropical seasonality in northern Australia

2002 ◽  
Vol 18 (4) ◽  
pp. 549-568 ◽  
Author(s):  
Gregory P. Brown ◽  
Richard Shine ◽  
Thomas Madsen
Keyword(s):  
Seasonal Variation ◽  
Sex Ratio ◽  
Body Condition ◽  
Reproductive Activity ◽  
Generalist Predator ◽  
Feeding Rates ◽  
Wet Season ◽  
Snake Species ◽  
Dry Tropics ◽  
Biological Attributes

In the Australian wet–dry tropics, temperatures are high year-round but rainfall is concentrated in a 4-mo wet season. Regular nightly surveys in the Fogg Dam Nature Reserve provided data on temporal (monthly, seasonal) variation in biological attributes of three snake species: water pythons (Liasis fuscus, Pythonidae), keelbacks (Tropidonophis mairii, Colubridae) and slatey-grey snakes (Stegonotus cucullatus, Colubridae). Adults of all three taxa were encountered more frequently during the dry season than the wet season, whereas juveniles were more commonly encountered in the wet season. The sex ratio among adult snakes also shifted seasonally, but in different ways in different species. These sex-ratio shifts probably reflect reproductive activity (mate-searching by males, oviposition migrations by females) and were accompanied by increased encounter rates. Feeding rates and body condition of keelbacks (a frog specialist) were highest during the wet season when frogs were most abundant. Rats migrated away from Fogg Dam during the wet season, and most pythons (rat specialists) left this area to follow their prey. The pythons that remained at Fogg Dam exhibited low feeding rates and poor body condition. Slatey-grey snakes (a generalist predator) showed less seasonal variation in feeding rates or body condition. Our data show that tropical seasonality induces strong fluctuations in many attributes of snake populations, and that patterns of response differ both among and within species.

scholarly journals Green extraction of proteins, umami and other free amino acids from brown macroalgae Ascophyllum nodosum and Fucus vesiculosus

2021 ◽  
Author(s):  
Viruja Ummat ◽  
Marco Garcia-Vaquero ◽  
Mahesha M. Poojary ◽  
Marianne N. Lund ◽  
Colm O’Donnell ◽  
...  
Keyword(s):  
Amino Acids ◽  
Citric Acid ◽  
Free Amino Acids ◽  
Free Amino ◽  
Food Industry ◽  
Ascophyllum Nodosum ◽  
Fucus Vesiculosus ◽  
Green Solvents ◽  
Brown Macroalgae ◽  
Extraction Solvent

AbstractSeaweeds are a valuable potential source of protein, as well as free amino acids (FAAs) with umami flavour which are in high demand by the food industry. The most commonly used flavouring agents in the food industry are chemically synthesised and therefore are subject to concerns regarding their safety and associated consumer resistance. This study focuses on the effects of extraction time (1 and 2 h) and solvents (0.1 M HCl, 1% citric acid and deionised water) on the extraction of protein and FAAs including umami FAAs from Irish brown seaweeds (Ascophyllum nodosum and Fucus vesiculosus). Extraction yields were influenced by both the extraction solvent and time, and also varied according to the seaweed used. Both seaweeds investigated were found to be good sources of protein, FAAs including umami FAAs, demonstrating potential application as flavouring agents in the food industry. Overall, the use of green solvents (deionised water and citric acid) resulted in higher recoveries of compounds compared to HCl. The results of this study will facilitate the use of more sustainable solvents in industry for the extraction of proteins and flavouring agents from seaweed.

scholarly journals Clinical Efficacy of Brown Seaweeds Ascophyllum nodosum and Fucus vesiculosus in the Prevention or Delay Progression of the Metabolic Syndrome: A Review of Clinical Trials

Molecules ◽  
2021 ◽  
Vol 26 (3) ◽  
pp. 714
Author(s):  
Enver Keleszade ◽  
Michael Patterson ◽  
Steven Trangmar ◽  
Kieran J. Guinan ◽  
Adele Costabile
Keyword(s):  
Metabolic Syndrome ◽  
Clinical Trials ◽  
Brown Seaweed ◽  
Public Health Problem ◽  
Ascophyllum Nodosum ◽  
Fucus Vesiculosus ◽  
Total Phenolic ◽  
World Population ◽  
Brown Seaweeds ◽  
The Metabolic Syndrome

Metabolic syndrome (MetS) is a global public health problem affecting nearly 25.9% of the world population characterised by a cluster of disorders dominated by abdominal obesity, high blood pressure, high fasting plasma glucose, hypertriacylglycerolaemia and low HDL-cholesterol. In recent years, marine organisms, especially seaweeds, have been highlighted as potential natural sources of bioactive compounds and useful metabolites, with many biological and physiological activities to be used in functional foods or in human nutraceuticals for the management of MetS and related disorders. Of the three groups of seaweeds, brown seaweeds are known to contain more bioactive components than either red and green seaweeds. Among the different brown seaweed species, Ascophyllum nodosum and Fucus vesiculosus have the highest antioxidant values and highest total phenolic content. However, the evidence base relies mainly on cell line and small animal models, with few studies to date involving humans. This review intends to provide an overview of the potential of brown seaweed extracts Ascophyllum nodosum and Fucus vesiculosus for the management and prevention of MetS and related conditions, based on the available evidence obtained from clinical trials.

scholarly journals Population biology of the crab Armases angustipes (Crustacea, Decapoda, Sesarmidae) at Brazilian tropical coast

2014 ◽  
Vol 104 (2) ◽  
pp. 150-161 ◽  
Author(s):  
Marina de Sá Leitão C. de Araújo ◽  
Deusinete de O. Tenório ◽  
Daniela da S. Castiglioni
Keyword(s):  
Population Structure ◽  
Sexual Dimorphism ◽  
Sex Ratio ◽  
Population Biology ◽  
Carapace Width ◽  
Reproductive Activity ◽  
Coastal Regions ◽  
Phytoplankton Productivity ◽  
Number Of Individuals ◽  
Tropical Coast

The semi terrestrial crabs are important elements of the fauna of coastal regions. The aim of this study was to analyze the population structure of Armases angustipes (Dana, 1852) at estuaries of the Ariquindá River, considered a non impacted area, and Mamucabas River, considered a few impacted area, on the south coast of state of Pernambuco, Brazil. The species occurred in all months of the year. The number of individuals per month varied, being higher in the months of transition between the seasons. This is probably due to significant seasonal variations of air and burrow temperature and burrow salinity. There was no sexual dimorphism in size of A. angustipes in the mangrove of Ariquindá River, but males were larger than females in the mangrove of Mamucabas River. In both estuaries, the sex ratio did not differ from Mendelian proportion, but showed a deviation for females. The analysis of temporal variation in sex ratio showed significant differences in some months of the year. These variations are due to cyclical events that act distinctly on each sex. In both estuaries, size classes of carapace width were equally represented by both sexes. The ovigerous females of A. angustipes occurred only in some months of the year, especially in summer, in both estuaries. Probably the high phytoplankton productivity observed in summer favors the reproductive activity, since these algae serve as food for the larvae. Specimens of the population of Rio Ariquindá are largest and wider than those of Mamucabas River. This fact, associated with the low abundance of crabs and the lower frequency of ovigerous females observed in Mamucabas River, is an indication that this population may be influenced by the environmental impacts that this estuary has received.

Relationships between environmental factors and biological parameters of Asian wedge clam, Donax scortum, morphometric analysis, length-weight relationship and condition index: a first report in Asia

2016 ◽  
Vol 97 (8) ◽  
pp. 1617-1633 ◽  
Author(s):  
Yambem Tenjing Singh
Keyword(s):  
Seasonal Fluctuation ◽  
Reproductive Activity ◽  
Condition Index ◽  
Maximum Sustainable Yield ◽  
Total Weight ◽  
Strong Positive Correlation ◽  
Biological Parameters ◽  
Shell Weight ◽  
Positive Correlation ◽  
Meat Weight

Wedge clam, Donax scortum occurrence was studied from February 2009 to January 2010 in Padukere sandy beach, Karnataka (India). The following biological parameters were measured in 2367 individuals of the wedge clam, Donax scortum: length, breadth, width, total weight, shell weight, wet meat weight, dry meat weight and number of clams. The calculated linear equation of length-breadth and length-width relationships were B = 3.5968 + 0.5421L and W = 0.8191 + 0.4345L respectively. The length-total weight, length-wet meat weight, length-dry meat weight and length-shell weight relationships were 0.0001414L3.0224, W = 0.0000037L3.5204, W = 0.0000011L3.4513 and 0.0000852L2.9912 respectively. The values of correlation coefficient for different shell dimensional relationships were very close to unity. It was clear from the study that the most ideal period for clam harvest was April, June and December, especially when condition index was maximum. Length showed a strong correlation with silt and clay. Dry meat weight was negatively correlated with air temperature. Shell weight showed positive correlation with length, breadth, width and dry meat weight, and abiotic parameters, silt and clay. Condition index was positively correlated with electrical conductivity, whereas it was negatively correlated with dissolved oxygen. It showed a strong positive correlation with salinity. Seasonal fluctuation of condition index in D. scortum was probably related to reproductive activity. The harvesting of wedge clam could be carried out considering the maximum sustainable yield without over-exploitation

scholarly journals Seasonal variation in the sex ratio of Arctodiaptomus salinus (Copepoda: Calanoida): does it agree with the “cheaper-sex” hypothesis?

2014 ◽  
Vol 36 (6) ◽  
pp. 1413-1418 ◽  
Author(s):  
Raquel Jiménez-Melero ◽  
Juan Diego Gilbert ◽  
Francisco Guerrero
Keyword(s):  
Seasonal Variation ◽  
Sex Ratio
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