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| Registros recuperados: 11 | |
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| Desprez, M; Ducrotoy, J; Elkaim, B. |
| In this paper, the results collected since 1978 on the cockle (Cerastoderma edule) in the Bay of Somme have been recapitulated. A synthesis is brought up about causes of the bivalve population collapse which was portended as early as 1982 from the animal cinetics study. In order to back up the discussion, the main results dealing with the biology and ecology of the species are recalled in illustrated form. A review of the international literature leads to a comment upon the diagrams. A comparison with data from European estuaries tends to take climatic and oceanic disturbances into account as well as local pollution such as eutrophication which is probable on the littoral of Picardy. |
| Tipo: Text |
Palavras-chave: Clam fisheries; Stock assessment; Recruitment; Population dynamics; Marine mollusks. |
| Ano: 1985 |
URL: http://archimer.ifremer.fr/doc/1985/publication-1783.pdf |
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| Ducrotoy, J; Desprez, M; Elkaim, B. |
| The recent collapse in the landings of cockles (Cerastoderma edule) from the Bay of Somme (France) required to investigate if a change in the environmental factors was liable for the drop of the bivalve populations. This project has led to a preliminary assessment of the situation and has been drawn up from the data collected by the Groupe d'Etude des Milieux Estuariens et Littoraux since 1978. It relies on the survey of the spatio-temporal changes of bio-facies. it is suggested that the impact of changes in sediment characteristics is important as well as competition with species as Pygospio elegans (Polychaeta). The above parameters are assessed as essential in the fluctuations of the cockle numbers but they do not explain entirely the collapse in the... |
| Tipo: Text |
Palavras-chave: Landing statistics; Clam fisheries; Stock assessment; Population dynamics; Marine mollusks. |
| Ano: 1985 |
URL: http://archimer.ifremer.fr/doc/1985/publication-1784.pdf |
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| Hamon, Pierre-yves; Tournier, Henri. |
| Since 1980, the IFREMER research laboratory "Resources Aquacoles", Sete (France), follows during the summer period, the evolution of the commercial stocks of molluscs (mussels and oysters) reared in Thau Lagoon. The data for this estimation are collected, on one hand, by surface observations and, on the other hand, by diving observations. During the years 1980 to 1984, the authors noticed an increase of oyster biomass, during the same period the mussel biomass decreased. The different simulations used to know the total filtration and the biodeposit, have shown that the impact of the increase of the total biomass is not so important as it could be feared. |
| Tipo: Text |
Palavras-chave: Bivalvia; Marine mollusks; Stock assessment; Population density; Biomass. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/publication-1787.pdf |
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| Santarelli, L; Gros, Philippe. |
| The totality of French landings of whelk (Buccinum undatum L.) is assignable to the fisheries of the Normand-Breton Gulf, western Channel. The aim of this paper is to forecast economic rent of the potters of the harbour of Granville, as a function of the two main variates open to supervision: the size of the fishing fleet, and the number of whelk-pots per ship. In order to assess the biological and financial consequences of a prospective development, a deterministic model of the fleet-resource system is proposed. Results of simulations emphasize the sharpness of the rent-dissipation problem under existing tendencies. Therefore some recommendations are put forward to derive a fishery policy that would enable the system to be maintained near optimal... |
| Tipo: Text |
Palavras-chave: Gastropoda; Marine mollusks; Fishery management; Economic models; Fishery economics. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/publication-1786.pdf |
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| Absalão,Ricardo Silva; Caetano,Carlos Henrique Soares; Pimenta,Alexandre Dias. |
| The gastropods Costaclis egregia (Dall, 1889), Thaleia nisonis (Dall, 1889), Tjaernoeia michaeli Engl, 2001 and the bivalves Bathyarca sp., Myonera aff. ruginosa (Jeffreys, 1882) are recorded for the first time in Brazilian waters. This paper presents a brief description of these species and also include ilustrations. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Bathyarca; Brazil; Costaclis; Marine mollusks; Myonera; New ocurrences; Thaleia; Tjaernoiea. |
| Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752003000200024 |
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| His, Edouard; Maurer, Daniele; Robert, Rene. |
| The spat production in the Bay of Arcachon has been recently disturbed. Bioassays using algae used as food for oyster larvae have shown that the organotin paints affect or inhibit growth of Isochrysis galbana and Chaetoceros calcitrans . Fresh waters coming into the bay and shore sediment did not affect the growth of these algae. Bioassays proposed by Woelke (1967) using embryos and larvae of Crassostrea gigas have shown that the quality of the sea water from Arcachon harbour has been improved a few months after the use of organotin paints has been prohibited. Likewise fresh waters are free from any micropollutants that could drastically disturb the reproduction of C. gigas in the bay. |
| Tipo: Text |
Palavras-chave: Marine mollusks; Pollution effects; Recruitment; Population number; Oyster culture. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/publication-1788.pdf |
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| Absalão,Ricardo Silva; Silva,Pedro Henrique de Almeida; Paula,Thiago Silva de. |
| Six morphometric shell direct measurements of the Gadilidae species Gadila acus (Dall, 1889), Cadulus braziliensis Henderson, 1920, Cadulus parvus Henderson, 1920 and Polyschides tetraschistus (Watson, 1879) were carried out and used to build three morphometric indices in according to the proposition of SHIMEK (1989): LI, relating total shell length to length from the dorsal aperture to the maximum width; WI, relating maximum shell diameter to apertural diameter; and Ws, whorl expansion rate (sensu RAUP 1966). Direct measurements and morphometric indices were tested as discriminating tools among the four species. None of the morphometric indices, alone, were able to discriminate among all species. Among then, Ws is not an effective discriminating... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cadulus; Conchology; Gadila; Marine mollusks; Polyschides. |
| Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752005000100020 |
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| Fernandes,Maurício Romulo; Pimenta,Alexandre Dias. |
| The taxonomy of the species of Metaxia Monterosato, 1884 from Brazil is revised. Previously to this study, only Metaxia excelsa Faber & Moolenbeek, 1991 was known to occur in this country, under its older name Metaxia exilis (C.B. Adams, 1850). The review of a large amount of shells in malacological collections in Brazil revealed the occurrence of three known additional species: Metaxia taeniolata (Dall, 1889); Metaxia rugulosa (C.B. Adams, 1850); Metaxia prompta Rolán & Fernández-Garcés, 2008, all previously reported from the southeast coast of the USA and/or the Caribbean region. Metaxia gongyloskymnus sp. nov., diagnosed by the globose protoconch with continuous axial ribs and microscopic spiral sculpture, is restricted to localities off... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Marine mollusks; Metaxiinae; Mollusca; Triphoroidea; West Atlantic. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702011000600016 |
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| Registros recuperados: 11 | |
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