3 resultados para PARITY-VIOLATION

em Aquatic Commons


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There have been numerous studies on various mammalian species regarding vascular changes in uterine arteries elucidating the effects of parity. In equids, vascular changes of uterine arteries have been demonstrated to occur in uniparous and multiparous mares. The severity of these arteriole changes suggests a link to previous pregnancies. Differences in the number or range of pregnancies can be ascertained through microscopic evaluation of elastin deposition in the arterioles, perivascular fibrosis, and stromal cellularity. There has been little, if any, work performed on parity in the bottlenose dolphin (Tursiops truncatus). The objective of this preliminary study was to determine the feasibility of detecting similar vascular changes in the endometrium of known-aged female bottlenose dolphins to assess parity. Archived formalin fixed samples of uterus were obtained from nine bottlenose dolphins with known age and parity. Four slides were made from each sample and individually stained with four different techniques. From our small sample pool, it appears that uteri from nulliparous animals do not develop perivascular fibrosis. Parous uteri developed perivascular fibrosis and arteriolar elastosis. These changes agree with our expectations that some degeneration (elastosis) and compensation (fibrosis) occurs as a result of uterine expansion of pregnancy. The assessment of this technique for use in bottlenose dolphins would provide an important tool in the determination of the reproductive success of dolphin populations, identify individuals who are sexually mature but nulliparous, which could indicate reproductive dysfunction or increased calving intervals, and increase our knowledge on the role contaminants play in reproductive dysfunction.

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This paper deals with the development and use of biological reference points for salmon conservation on the River Lune, England. The Lune supports recreational and net fisheries with annual catches in the region of 1,000 and 1356 salmon respectively. Using models transported from other river systems, biological reference points exclusive to the Lune were developed; specifically the number of eggs deposited and carrying capacity estimates for age 0+ and 1+ parr. The conservation limit was estimated at 11.9 million eggs and between 1989 and 1998 was exceeded in two years. Comparison of juvenile salmon densities in 1991 and 1997 with estimates of carrying capacity indicated that 0+ and 1+ parr densities were at around 60 % of carrying capacity and may relate to the number of eggs deposited in 1990 and 1996 being approximately 70% of the target value. The paper discusses the management actions taken in order to ensure that the management target of the conservation limit being met four years out of five is delivered. It also discusses the balance between conservation and exploitation and the socio-economic decisions made in order to ensure parity of impacts on the rod and net fisheries. The regulations have been enforced since 1999 and the paper concludes with an assessment of the actions taken to deliver the management targets, over the last five years.

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As the earth’s resources continue to face increasing pressure from a variety of human and natural causes, protection of the environment and biodiversity is a matter of contemporary concern, The conservation of coastal and marine resources, in particular, has become a priority for countries around the world. In this context, marine protected areas (MPAs) are being widely promoted as one of the most effective tools for the conservation of coastal and marine resources. Most MPAs are located in coastal areas of great biodiversity, and hence their development has direct impacts on the lives and livelihoods of coastal communities, especially small-scale and traditional fishing communities. Typically, they are the ones who have to bear the costs of conservation practices–lost livelihood options, expulsion from traditional fishing grounds and living spaces, and violation of human/community rights, to name a few. The articles in this dossier, drawn chronologically from the pages of Samudra Report, the triannual publication of ICSF, draw attention to these issues. They show that conservation and livelihoods are closely intertwined, and that top-down, non-participatory models of conservation can be counter-productive. Despite being poor and powerless, fishing and coastal communities can be powerful allies in conservation efforts, given their longstanding dependence on natural resources and their traditional ecological knowledge systems. As the examples in this dossier reveal, it is possible for fishing communities to protect and conserve the environment, while continuing with sustainable fishing operations. Clearly, only an integrated approach to fisheries management and conservation will prove successful. This dossier will be useful for policymakers, social scientists, non-governmental organizations and others interested in fisheries, conservation, communities and livelihoods.