Diets of calanoid copepods on the West Florida continental shelf: Relationships between food concentration, food composition and feeding activity

Abstract In 2014 Japan’s Cabinet Order No. 302 declared the outer limits of its continental shelf beyond 200 nautical miles (OL) to the west and north of Oki-no-Tori Shima (Area 302). Oki-no-Tori Shima consists of two small, barren, and uninhabitable rocks in the West Pacific. The northern part of Area 302 is broader than what the 2012 recommendations of the Commission on the Limits of the Continental Shelf (CLCS) specify. A question arises whether Order No. 302 violates Article 76(8) of the United Nations Convention on the Law of the Sea (UNCLOS), which provides that the OL established by a coastal state ‘on the basis of’ the CLCS recommendations shall be final and binding. Another question is the role played by the CLCS in ‘assisting’ the coastal states to delimit their national jurisdiction so as to know where the Area (i.e., the Common Heritage of Mankind under UNCLOS Articles 1(1)(1) and 136) begins. The essential questions arising from Area 302 concern how well the UNCLOS mechanism can perform to safeguard the Common Heritage of Mankind through preventing encroachment thereupon by individual coastal states. This article looks at the context and explores the obligations implied by Article 76(8) for coastal states to ‘follow’ the recommendations in establishing the OL, with special reference to the northern part of Area 302. The article also examines legal consequences arising from a breach of these obligations.

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Assessing Bypassed Hydrocarbons

10.2118/207086-ms ◽

2021 ◽

Author(s):

Stanley Oifoghe ◽

Nora Alarcon ◽

Lucrecia Grigoletto

Keyword(s):

Continental Shelf ◽

Reservoir Characterization ◽

Gamma Ray ◽

West African ◽

The Novel ◽

The West ◽

Present Case Study ◽

Novel Model

Abstract Hydrocarbons are bypassed in known fields. This is due to reservoir heterogeneities, complex lithology, and limitations of existing technology. This paper seeks to identify the scenarios of bypassed hydrocarbons, and to highlight how advances in reservoir characterization techniques have improved assessment of bypassed hydrocarbons. The present case study is an evaluation well drilled on the continental shelf, off the West African Coastline. The targeted thin-bedded reservoir sands are of Cenomanian age. Some technologies for assessing bypassed hydrocarbon include Gamma Ray Spectralog and Thin Bed Analysis. NMR is important for accurate reservoir characterization of thinly bedded reservoirs. The measured NMR porosity was 15pu, which is 42% of the actual porosity. Using the measured values gave a permeability of 5.3mD as against the actual permeability of 234mD. The novel model presented in this paper increased the porosity by 58% and the permeability by 4315%.

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LATE QUATERNARY STRATIGRAPHIC EVOLUTION OF THE WEST LOUISIANA/EAST TEXAS CONTINENTAL SHELF

Late Quaternary Stratigraphic Evolution of the Northern Gulf of Mexico Margin ◽

10.2110/pec.04.79.0217 ◽

2004 ◽

pp. 217-235

Author(s):

JULIA S. WELLNER ◽

SABRINA SARZALEJO ◽

MARTIN LAGOE ◽

JOHN B. ANDERSON

Keyword(s):

Continental Shelf ◽

Late Quaternary ◽

East Texas ◽

The West ◽

Stratigraphic Evolution

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Diel feeding pattern and diet of rough scad Trachurus lathami Nichols, 1920 (Carangidae) from the Southwestern Atlantic

Neotropical Ichthyology ◽

10.1590/s1679-62252006000400005 ◽

2006 ◽

Vol 4 (4) ◽

pp. 419-426 ◽

Cited By ~ 8

Author(s):

Maria Raquel de Carvalho ◽

Lucy Satiko Hashimoto Soares

Keyword(s):

Feeding Activity ◽

Stomach Contents ◽

Feeding Time ◽

Frequency Of Occurrence ◽

Southwestern Atlantic ◽

Calanoid Copepods ◽

Teleostean Fish ◽

Dark Cycle ◽

Percent Number ◽

Decapod Larvae

Diel changes in feeding activity and dietary composition of the rough scad Trachurus lathami were investigated through the analysis of stomach contents of 307 fish sampled over a 24-h period on the continental shelf off Ubatuba (23º 35'S 45ºW). Stomach contents were analyzed by frequency of occurrence (O%), percent number (N%), percent mass (M%), and feeding index (FI% = O% * M%). Rough scad fed on mollusks (Gastropoda, Crepidula sp.), crustacean (Ostracoda, Copepoda, decapod larvae), chaetognat and teleostean fish. The main items were calanoid copepods (Eucalanus sp. and Centropages sp.). According to the analysis of the stomach fullness and prey digestion, T. lathami is both a diurnal and nocturnal feeder, showing some seasonal variation in feeding time. According to the Chronobiology concept, it was raised the hypothesis of circadian rhythm in feeding of this fish, probably synchronized by light/dark cycle.

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Variations of Salminus hilarii diet (Ostariophysi, Characidae): seasonal and ontogenetic effects

Brazilian Journal of Biology ◽

10.1590/1519-6984.17213 ◽

2015 ◽

Vol 75 (3) ◽

pp. 574-580

Author(s):

GA Villares Junior ◽

R Goitein

Keyword(s):

Prey Size ◽

Pearson Correlation ◽

Feeding Activity ◽

Stomach Contents ◽

Food Composition ◽

Spearman Correlation ◽

Statistical Comparison ◽

Significant Difference ◽

Ontogenetic Effects ◽

Size And Morphology

AbstractThis study described the variations seasonal and ontogenetic of Salminus hilarii diet. Samples were collected in the Sorocaba River, São Paulo, Brazil, one of the few rivers where individuals of the species still occur in a higher frequency. The preys consumed were analyzed by Importance Alimentary Index (AIi). To determine similarities between year seasons, the AIi data were analyzed by the Morisita-Horn index and reduced in cluster analysis, along with a statistical comparison made by one-way ANOSIM test (5%). The feeding activity was analyzed according to the stomach repletion index and compared among the year seasons using non parametric variance analysis Kruskal-Wallis test (5%). Comparison of prey consumed between immature and adult individuals was made by Spearman correlation (5%). A Pearson correlation (5%) was applied between the standard length of the fish and prey consumed, as well as between the mouth and prey heights. The analyzes of stomach contents showed that the diet of this species was exclusively piscivorous, with significant difference of prey consumption during the period, the same happening among adult and immature individuals. It was observed that these fishes use to swallow their prey whole and that significant correlations between size of predator and prey size can be observed. There is also correlation between the mouth height and the maximum prey depth. Salminus hilarii feeds on the available prey, and the species food composition and feeding activity depends on prey`s abundance, their size and morphology, as do the water temperatures.

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