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Les pêcheries mixtes de langoustine et de merlu du golfe de Gascogne. Description, préparation à une modélisation et à une simulation des procédures de gestion
Auteur(s) : Charuau, Anatole Ifremer

Résumé : 1 - Study's goals review The management of Norway Lobster and Hake fisheries can be considered as the most important issue in the Gascogne gulf. Calculation methods used to evaluate prediction variations under various efforts and mesh constraints all pinpoint to the crucial role narrow mesh fishing plays in Hakes' Northern stock status. The involvement of Gascogne gulf Norway Lobster fisheries regarding Hakes over exploitation seems over dimensioned when comparing the size of both of these stocks. Hake stocks spread from Northern Great Britain to Northern Spain, while Norway Lobster stocks are located in the Gascogne gulf's mud flats. The biological solution is well known and consists in globally increasing mesh nets to 80mm which would bring up Hakes yield to its most. It would be unreal to pretend all parties involved in Hake stocks will come to use them. For now, it is mostly an economical issue since many vessels continue on with an exploitation scheme dating from the 60's and fish on coastal mud flats which are the most exploited zones and where their catch is detrimental to juvenile class Hakes and Norway Lobsters. Considering our limited time, this study will cover bio- economical modelisation preparation. You will therefore find a description of fisheries and an exploitation assessment based on 1986's available data. 2 - Accomplished work 2. 1 Fishery description Presenting the problems and preparing ulterior analyses was first and foremost. Norway Lobster vessels supposedly, according to evaluation models used, test immature Hakes in such a manner that all stock exploitation is jeopardized. Norway Lobster distribution is closely linked to the nature of the ocean floor since it can only build its habitat on fine sediment. Hakes' habitat is not as restrictive and is linked to food supply, especially euphausiid shrimps, so they can be found on sandy and sandy-sedimental floors. Norway Lobsters are sought by a fleet of 400 to 450 ships which characteristics widely vary according to their home port. On the northern part, fisheries are close to exploitation ports where Norway Lobsters and miscellaneous catch yield is sufficient to support an older fleet. On the southern part, the structure is diversified and flexibility usually rules, more modern vessels can easily switch their target on a seasonal or daily basis. Globally, Hakes' northern stocks are slightly on the rise. This rise is probably due to global mesh size increase, even if slight and a decrease on fishing effort where immature species are caught. Norway Lobster stocks unloading is stable or slightly lower and yields, as far as northern fishery are concerned, vary and oscillate between ±15 to ±20 % at about an average of 100 kg/day. Biological parameters used in the evaluations for each species are those used in CIEM and CEE work cells. Among those parameters, those describing growth are the greatest. For Hakes, an intermediary growth equation between males and females has been used. For Norway Lobsters, both sexes are treated separately. Simulations were carried out according to 3 types of data: Norway Lobster vessels fishing effort variations. Norway Lobster vessels mesh increase. Norway Lobster vessels fishing effort decrease or mesh increasing go along in the same direction for Hake and Norway Lobster stock production (chart A and B). Lastly, a brief study on results evaluation significance was done to modify: - the size of Hake rejects by Norway Lobster vessels. The range of sizes stays the same but the amount in each class varies according to the same percentage. - Norway Lobsters growth parameters, both values used (L» = 76 mm and k = 0.11 for males, L°° = 56 mm and k = 0.14 for females) representing the "high" hypothesis. In the first case, a 20% error rate for rejects evaluation with 60 mm mesh would only bring a 3% modification rate on global stock production. Those first results are contradicting usual evaluation conclusions and it will be necessary to recalculate by modifying the size class step. In the second case, to decrease L» and increase growth speed, in time production variations remain within usual inter annual fluctuations. In all figure cases, calculations confirming greater yield for in time production through hypothetical mesh size increase to 60 mm, are definitely well founded.
1 - Rappel des buts de l'étude La gestion des pêcheries de merlu et de langoustine peut être considérée comme le problème le plus important du Golfe de Gascogne. Les méthodes de calcul employées pour évaluer les variations de la production sous diverses contraintes d'effort et de maillage mettent toutes l'accent sur le rôle capital des pêcheries à petits maillages sur l'état du stock nord de merlu. Le niveau de responsabilité des pêcheries de langoustine du Golfe de Gascogne dans la surexploitation du merlu semble démesuré eu égard aux dimensions respectives des deux stocks. Le stock de merlu s'étend du Nord des Iles Britanniques au Nord de l'Espagne alors que le stock de langoustine est localisé aux vasièrés du Golfe de Gascogne. La solution biologique du problème est connue et tient à une augmentation généralisée des maillages à 80 mm qui amènerait le rendement du stock de merlu à son maximum. Il serait illusoire de prétendre que tous les acteurs opérant sur le stock de merlu arriveront jamais à l'utiliser. Pour le moment, le problème se pose essentiellement en termes économiques car beaucoup de navires poursuivent un schéma d'exploitation hérité des années 1960 et pèchent sur des vasièrés côtières qui sont les zones les plus exploitées et où ils effectuent leurs captures au détriment des jeunes classes d'âge de merlu et de langoustine. En raison des délais impartis, cette étude constitue la préparation à une modélisation bioéconomique. On y trouvera donc une description des pêcheries et un bilan de l'exploitation sur les données disponibles en 1986. 2 - Travaux effectués 2 . 1 Description de la pêcherie Il s'agissait avant tout de poser les problèmes et de préparer les analyses ultérieures. Les langoustiniers sont présumés, d'après les modèles d'évaluation employés, effectuer sur les immatures de merlu des prélèvements tels qu'ils mettent en danger toute l'exploitation du stock. La distribution de la langoustine est très liée à la nature du fond car elle ne peut construire son terrier que sur des fonds de vase fine. Celle du merlu est beaucoup plus large et inféodée à la recherche de nourriture, crevettes euphausiacées en particulier, on le trouve donc sur les fonds sableux à sablo-vaseux. La langoustine est recherchée par une flottille de 400 à 450 bateaux dont les caractéristiques sont très variables suivant leur appartenance géographique. Au nord, la pêcherie est proche des ports exploitants et les rendements en langoustine et en prise accessoire sont suffisants pour faire vivre une flottille ancienne. Vers le sud, la structure est très diversifiée et la flexibilité est généralement la règle et les navires de construction récente peuvent changer de cible aisément de façon saisonnière ou au cours de la même journée de pêche. Globalement, les débarquements de merlu du stock nord sont en légère hausse. Ce redressement est dû probablement aux augmentations de maillage, même légères, généralisées et à une baisse de l'effort sur les pêcheries où s'effectuent des captures d'immatures. Les débarquements de langoustine sont stables ou en légère baisse et les rendements, au moins sur la pêcherie du nord, varient avec des oscillations de ±15 à ±20 % autour d'une moyenne de 100 kg/jour. Les paramètres biologiques utilisés pour chaque espèce dans les évaluations sont ceux en usage dans les groupes de travail du CIEM et de la CEE. Parmi ces paramètres, ceux décrivant la croissance sont les plus importants. Pour le merlu une équation de croissance intermédiaire entre mâles et femelles a été utilisée. Pour la langoustine les deux sexes sont traitées séparément. Les simulations ont porté sur trois types de données : Variations de l'effort des langoustiniers Augmentation du maillage des langoustiniers La diminution de l'effort des langoustiniers ou L'augmentation de maillage agisse très exactement dans le même sens sur la production des stocks de merlu et de langoustine. Enfin une étude succincte de la sensibilité des résultats des évaluations a été effectuée pour des modifications : - de la composition en taille des rejets de merlu par les langoustiniers. L'étendue des tailles reste la même mais le nombre dans chaque classe varie selon le même pourcentage. des paramètres de croissance de la langoustine, le couple de valeurs utilisées (L» = 76 mm et k = 0.11 pour les mâles, L°° = 56 mm et k = 0.14 pour les femelles) constituant l'hypothèse "haute" Dans le premier cas, une erreur de 20 % sur l'évaluation des rejets pour un cnaillage de 60 mm n'apporterait qu'une modification de 3 % dans la production globale du stock. Ces premiers résultats sont en contradiction avec les conclusions habituelles des évaluations et il sera nécessaire de reprendre les calculs en modifiant le pas des classes de taille. Dans le deuxième cas, pour une diminution de L» et une augmentation de la vitesse de croissance, les variations de la production à terme restent à l'intérieur des fluctuations interannuelles habituelles. Dans tous les cas de figure, les calculs confirmant l'augmentation de la production à terme dans l'hypothèse d'une augmentation de maillage à 60 mm sont d'une robustesse à toute épreuve.

Droits : 1987 Ifremer
http://archimer.ifremer.fr/doc/1987/rapport-1763.pdf
http://archimer.ifremer.fr/doc/00000/1763/

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Life in the yaguas, Photographs by Aida Garcia Alonso
Auteur(s) : García Alonso, Aida

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Socioeconomic considerations in multiple cropping systems
Auteur(s) : Hildebrand, Peter E. Instituto de Ciencia y Tecnologia Agricolas

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Life in the yaguas, Photographs by Aida Garcia Alonso
Auteur(s) : García Alonso, Aida

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Life in the yaguas, Photographs by Aida Garcia Alonso
Auteur(s) : García Alonso, Aida

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True stories of the favorites sons and daughters of America for young people
Auteur(s) : Abbott, John S. C ( John Stevens Cabot ), 1805-1877 Abbott, John S. C ( John Stevens Cabot ), 1805-1877 ( Editor ) Garnett, William, 1850-1932 ( Editor ) Birdsall, William W ( William Wilfred ), 1854-1909 ( Editor ) Ellis, Edward Sylvester, 1840-1916 ( Editor ) World Bible House

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St. Lucia ; Saint Lucia
Auteur(s) : Saint Lucia -- Ministry of Planning, Personnel, Establishment, and Training United States -- Agency for International Development Caribbean Conservation Association Island Resources Foundation (Virgin Islands of the United States) National Research and Development Foundation (Saint Lucia)

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Guatemala
Auteur(s) : United States -- Army Map Service United States -- Army Map Service United States -- Defense Mapping Agency Instituto Geográfico Nacional (Guatemala) Guatemala -- Dirección General de Cartografía Honduras -- Dirección General de Cartografía Inter American Geodetic Survey

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Bibliography ; Gender issues in Latin America and the Caribbean
Auteur(s) : Mauzé, Suzanne B GENESYS Project United States -- Agency for International Development. -- Office of Women in Development

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Forum with Parliament Members : Students Against Sexual Orientation Discrimination ; Audio Recordings of the Proceedings
Auteur(s) : Caribbean IRN

Résumé : From the PNCR, GAP MPs free to vote conscience on gay rights bill By Johann Earle Stabroek News June 11, 2003 The PNCR will allow its members to vote their conscience on the controversial Constitution (Amendment) Act of 2001 which seeks to prevent discrimination against persons on the basis of their sexual orientation and other grounds. A number of religious organisations are opposed to the passage of the bill because it includes sexual orientation as one of the grounds. They are concerned that it could lead to a legalisation of homosexual relations and demands for recognition of gay marriages among other things. PNCR Member of Parliament (MP) Vincent Alexander told a forum at the National Library on Saturday, that the Bill did not seek to legalise homosexuality, but to ensure that persons would not be discriminated against based on their sexual preferences. He was one of two parliamentarians who showed up - the other being PNCR member, Myrna Peterkin. The forum was organised by Students Against Sexual Orientation Discrimination (SASOD), a group comprising fifteen students from the University of Guyana which was formed about two weeks ago. Alexander expects the vote on the bill to come up before the National Assembly in a matter of months. Paul Hardy, Leader of the Guyana Action Party (GAP), told Stabroek News that his party would not be using the so-called parliamentary whip. He added that GAP took a decision that every member should vote according to his or her own conscience. “We have no right to deny the rights of others based on sexual orientation. [The Bill] will guarantee rights to the homosexual.” GAP is in Parliament as part of an alliance with the Working People’s Alliance. GAP/WPA has two MPs. The bill was met with rejection from some members of the religious community in 2001 and as a result of this, the President did not assent to it. In a statement on Monday, the Central Islamic Organisa-tion of Guyana (CIOG) said that it stood in firm opposition to the Bill. The CIOG says the general purpose of the bill may be commendable and that the organisation’s objection is not based on a willingness to promote discrimination. Rather, the CIOG said, it was based on the fact that specific legal protection on the basis of sexual orientation without definition or qualification gives tacit legitimacy to practices which are considered criminal in Islam. “It is foreseeable that such a legal nod of approval (subtle as it may be) of these practices may pave the way for greater social (or even legal) acceptability in the future which, from the perspective of all Muslims including those in Guyana, is an undesirable and sinful outcome,” the CIOG statement said. At Saturday’s event, Muslim teacher Moulana Mohamed Ali Zenjibari spoke of instances of abuse, discrimination and harsh penalties meted out to gay and lesbian persons in countries such as Iran and Saudi Arabia and noted that the Quran did not sanction such punishments for homosexual behaviour. President of the CIOG, Fazeel Ferouz told Stabroek News that a meeting to discuss a strategy with regards to the bill was planned for tomorrow with various religious groups. Stabroek News tried to get a comment on the issue from the PPP/C but to no avail. ROAR leader, Ravi Dev said that his party was now having discussions on the issue. ROAR feels that it is an important question which has to do with morality and should be discussed across the country. He added legislators had to be in tune with their constituents on the issue. SASOD is lobbying for the legislation through the sensitisation of MPs. Keimo Benjamin, a law student at UG, gave a presentation based on the jurisprudential aspects of the discussion on sexual orientation. He argued that morality should not be the only guiding principle on which to base the laws. Sexual activities between two consenting male adults in private could not be equated with a violation of a person’s rights, he said, making the point that the thrust of his presentation was not whether homosexuality was wrong, but whether it violated the rights of others. He said that the attitudes of some towards this subject were based on preconceived notions and prejudices. He cited studies to show that the suppression of certain perceived deviant sexual impulses in persons might do more harm than good. One Harvard University study of teens who said they were gay indicated that those teens were three times more likely to commit suicide. Vidyaratha Kissoon, of Help and Shelter, in his contribution on Saturday, expressed his displeasure at the low turnout at the forum and urged the parliamentarians who showed up to take the message to their colleagues. He noted that because of homophobia, the numerical minority was terrified of speaking out against instances of discrimination. Gays and lesbians in Guyana were subjected to ridicule and abuse, and walk the streets at night not looking for sex necessarily, but for the companionship of persons who empathise with them. During his presentation, Joel Simpson, another member of SASOD, outlined a number of changes made within national jurisdictions that had international implications. One such crucial change was South Africa’s 1996 adoption of a new constitution, making that country the first in the world to expressly include sexual orientation as a prohibited ground of discrimination. It was the first time a developing country had taken the lead with respect to the rights of sexual minorities. He also said that according to Douglas Sanders, a Canadian jurist, the rights of homosexual, bisexual or transsexual men and women had never been officially recognised by the United Nations, despite the fact that international laws on the issue began to emerge at the close of the Second World War. Simpson said that under Article 170 (5), as amended by Section 8 of the Constitution (Amendment) (No. 4) Act 2000, the President is required to assent to any bill which is returned by the National Assembly unaltered after a two-thirds majority within 90 days of its presentation to him. To the parliamentarians present, Simpson stressed that the onus was now on them to adequately represent their constituents which include lesbian, gay, bisexual and transsexual Guyanese. http://www.landofsixpeoples.com/news301/ns306115.htm and Vote on sexual orientation should be a matter of conscience - MP Alexander By Esther Elijah Guyana Chronicle June 8, 2003 PEOPLE’S National Congress (PNC/R) Member of Parliament Mr. Vincent Alexander, said the Opposition will vote on “conscience” when the piece of legislation on sexual orientation is again brought before the National Assembly. “With specific reference to my party, when this Bill gets back to the Parliament in the spirit of the arguments here, we will not use the `whip’. Our party will not say we have to vote for the provision (in the Sexual Orientation Bill). We will allow our members to vote as a matter of conscience,” he told participants gathered in the Conference Room of the National Library. “We feel this is a matter of conscience. You may end up with a collective position but you have to deal with us individually,” Alexander said at a poorly attended public consultation aimed at gaining support for sexual orientation to be considered a fundamental right in Guyana. Alexander, one of the main persons who sat on the Constitutional Reform Commission that addressed this controversial clause, said the legislation was not meant to legalise homosexual activities in Guyana. “It was intended to ensure that persons who have an orientation - a way of thinking - which may or may not lead to a certain activity, to not be discriminated against, in terms of their rights,” he explained. Alexander noted that very often, discussions on the sexual orientation provision in the Bill have led to seepages into other areas where debates centre on the “right to be homosexual.” “I am saying the Bill does not comment on that… However, law is peculiar, especially in a Common Law system. Once you venture out and change the law, very often you open other windows which we cannot definitively say exist or does not exist in advance,” he said. “The fear of some people is that the legislators might say one thing and the Courts will eventually say something else. While some people can’t argue against the law, per say, they will say this has opened a window of opportunity not meant to be opened. So, it is better to stay without a window than open it and then have a possibility of something you didn’t intend to happen - happening sometime in the future.” Alexander added: “I want to say I’ve found this activity to have been rich from the perspective of the amount of research which was done by student (speakers). Without any comment as to whether I agree with the arguments, I would wish that much more research on other issues be done by students, and that at the University (of Guyana) students would find it convenient to have forums on other issues, with the same depth of research for their own intellectual development.” Alexander and other Opposition M.P, Lurlene Nestor were the only three Parliamentarians in attendance at the session organised by the recently formed `Students Against Sexual Orientation Discrimination’ (SASOD), a group that has a membership of 15 mostly University of Guyana (UG) students from various faculties. SASOD was established two weeks ago. With the exception of members of the press, the consultation only managed to attract 11 persons, a handful of who were SASOD members. While congratulating the students for an “insightful” presentation, Nestor pointed out that whether or not she chooses to agree with their position is “another issue” and she is entitled to her “own view”. “The issue of sexual orientation is very `toucheous’ …while we agree with the human rights provisions and all that as a society, we must also revert to our own society. Some of the very critical questions that I would want to ask is whether or not at the society (level) we are ready for that kind of thing,” she remarked. “We cannot, at (any) time, ignore the religious groups in our society. If we look at statistics going back to 1992 from a survey done by the Bureau of Statistics, we would see that a small section of the Guyanese population might be considered as people who do not subscribe to a religious view. While the laws are not necessarily based on moral values, we must acknowledge the fact that we might want to revert to many of the cases that (concern) laws that protect public morality.” Nestor told the speakers at the consultation these were some of the issues that they needed to deal with. She highlighted, too, that what must be examined is the effects of same-sex marriages on society and how this issue must be tackled. “These are some of the things we should consider and I don’t think you dealt with that in the presentations,” Nestor stated, adding that the issues must be addressed “frontally.” “Do we think that with the coming to being of this Bill that there might be quite a number of challenges to the Constitution in relation to the same issue of a man marrying a man? What do we do at the society (level)? Do we recognise that?” were the questions directed at the five speakers at the session. Nestor continued: “There is some argument that says, `Oh the Bill does not promote homosexuality or does not encourage a man to marry (another) man, but if you look at Section (15) that talks about `non-discrimination’ then how can we not, with the passage of this Bill, allow a man not to marry (another) man.” According to Nestor, matters of this nature constitute some of the “inconsistencies” of the Bill. On the argument raised by presenters at the session on who determines what is morality, Nestor said in the concept of democracy it is the people who are the determinants based on a “line of thinking.” She also rebutted on grounds that put the spotlight on teachers who may have been caught “interfering” with their young students and who may subsequently be dismissed from their jobs. “Could you imagine such a person interfering with a boy below age 10 - and by virtue of the fact that the Bill is there, the judges (in the case) will have to use their discretion in terms of what happens. We will have more Constitutional changes and problems (arising with the passage of the Bill).” SASOD member and law student, Joel Simpson, in reply, said he doesn’t think any homosexual in Guyana wants to “run into a church and ask that people marry them or anything of that sort.” At one point likening the church to a “club”, Simpson claimed the church has the right to exclude whomever it wants. He further stated that in accordance with the Constitution, people of the same sex do not currently have the right to marry, and will also not be able to do such an act with the passage of the Bill. However, Simpson said it is possible that the law, with the passage of the Bill, would have to recognise same-sex domestic partnerships in relation to employment benefits, sharing of properties, etc. Simpson said he believes there should be a realm of “public” and “private” morality between consenting adults, and implied that the Bill did not fully give “rights” to homosexuals. But, Nestor interjected: “I am informing you further…that the Sexual Orientation provision has, in fact, in some way recognised the rights of homosexuals and we must accept that.” Meanwhile, there was no vocal Christian representative(s) at the consultation and apart from the two Opposition representatives none other participant gave comments or directed questions at the presenters. Other speakers in support of the sexual orientation clause were: Moulana Mohammed Ali Zenjiban, Assistant Director of the International Islamic College; Denuka Radzik from Red Thread, Keimo Benjamin, UG law student and Vidyartha Kissoon from Help & Shelter. The Sunday Chronicle has been reliably informed that the Georgetown Ministers Fellowship, representing groups of Christian leaders staunchly against sexual orientation as a right in Guyana, have recently prepared a detailed 16-page document outlining issues arising from research to further boost their argument against the inclusion of the clause. The document is yet to be made public. http://www.landofsixpeoples.com/news301/nc306083.htm

Droits : All rights reserved by the source institution.
http://ufdc.ufl.edu/AA00014700/00001

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