Vertical transport and exchange of materials in the upper waters of the oceans (VERTEX): introduction to the program, hydrographic conditions and major component fluxes during VERTEX I

This paper introduces VERTEX, a multi-disciplinary research program dealing with various aspects of particle transport in the upper, high-energy layers (0-2000 m) of the ocean. Background information is presented on hydrography, biological composition of trapped particulates, and major component fluxes observed on a cruise off central California (VERTEX I). Organic C fluxes measured with two trap systems are compared with several other estimates taken from the literature. The intent of this overview paper is to provide a common setting in an economical manner, and avoid undue repetition of background and ancillary information in subsequent publications. (PDF is 43 pages).

National policy framework and strategy for fisheries and aquaculture development in Pakistan: final national workshop Islamabad, 30-31 Oct. 2006

The Final National Workshop was held from 30-31 October 2006 in Islamabad, Pakistan, with the objectives to:

Sexual Reproduction and Early Development in the Estuarine Sea Anemone, Nematostella vectensis Stephenson, 1935

This dissertation: 1) determines the factor(s) responsible for spawning induction in NematosteJla vectensis; 2) isolates, describes, and documents the source of jelly from egg masses of N. vectensis; and 3) describes N. vectensis' early development. Namatostella vectensis were maintained on a 7-day mussel feeding/water change regime over 159 days. Within 36 hours of mussel feeding/water change. 69.1% of females and 78.5% of males spawned reliably. Through manipulation of feeding, water change, oxygen and nitrogenous waste concentrations, spawning induction was found to be triggered by the oxygen concentration associated with water change, and not by feeding. Ammonia, anemones' major waste product, inhibited this induction in a concentration-dependent manner. Female N. vectensis release eggs in a persistent jellied egg mass which is unique among the Actiniaria. The major component of this egg mass jelly was a positive periodic acid-Schiffs staining, 39.5-40.5 kD glycoprotein. Antibodies developed in rabbits against this glycoprotein bound to jelly of intact egg masses and to granules (~ 2.8 IJm in diameter) present in female anemone mesenteries and their associated filaments. Antibodies did not label male tissues. Nematostella vecfensis embryos underwent first karyokinesis -60 minutes following the addition of sperm to eggs. Second nuclear division took place, followed by first cleavage, 90-120 minutes later. Each of the 4 blastomeres that resulted from first cleavage contained a single nucleus. Arrangement of these blastomeres ranged from radial to pseudospiral. Embryonic development was both asynchronous and holoblastic. Following formation of the 4-cell stage, 71% of embryos proceeded to cleave again to form an 8-cell stage. In each of the remaining 29% of embryos, a fusion of from 2-4 blastomeres resulted in 4 possible patterns which had no affect on either cleavage interval timing or subsequent development. The fusion event was not due to ooplasmic segregation. Blastomeres isolated from 4-celled embryos were regulative and developed into normal planula larvae and juvenile anemones that were 1/4 the size of those that developed from intact 4-celled embryos. Embryos exhibiting the fusion phenomenon were examined at the fine structural level. The fusion phenomenon resulted in formation of a secondary syncytium and was not a mere compaction of blastomeres.

Fishery management plans and the development of artisanal fisheries in Nigeria: a review

Management of natural resources all over the world is of paramount importance to their sustainability in developing countries like Nigeria, there is less emphasis on proper management especially of fishery and other aquatic resources due to lack of sensitization and enlightenment of the rural dwellers who are closer to such natural resources. The main thrust of this review is to examine the management plans for Nigerian freshwater bodies (rivers and lakes) and the impact of such plans on the artisanal fisheries development in Nigeria. From the on-shelf information gathered there is scarcity of information on the management of Nigerian freshwater body's information available indicates that there is the traditional fisheries management and the government legal approach in form of fisheries Laws and Regulations. However, these management techniques are poorly carried out since there is a poor follow-up. Appreciable impact of fisheries management introduced on Kanji Lake by the Nigerian-German Kanji Lake Fisheries Promotion Project (NGKLFPP) between 1993 and 2001 proves worthwhile as this introduced some management measures such as implementation of fisheries Laws and Regulations, the ban of obnoxious fishing methods, introduction of fishing license, constitution of a management unit and appointment of liaison fishermen. Within the operative years of the project a lot of success was achieved and it is recommended that the approach in Kainji should be replicated in other freshwater bodies in Nigeria to alleviate poverty in the rural poor fishing communities

Impact of Nigerian Agricultural Cooperative and Rural Development Bank (NACRDB) loan to artisanal fishermen in Lake Kainji

This study was conducted to assess the impact of Nigerian Agricultural, Co-operative and Rural Development Bank Loan on beneficiaries and non-beneficiaries fishermen in Lake Kainji. A total of fifty fishermen (25 beneficiaries and 25 non-beneficiaries) were randomly selected from five fishing villages along the lake basin. Data collected were scored and the percentages of the parameters were calculated appropriately. The types of loans disbursed to beneficiaries revealed that 52% was cash and 48% was in kind. The credit package ranged between N5, 000 to N150, 000 only. Only 48% of the loans granted were paid while the rest remained unpaid. The results obtained from the membership of fishermen Cooperative showed that 64% of beneficiaries were members while 36% were non-members. Also 36% of non-beneficiaries were members while 64% were not. The Common fishing gears used by the two categories of fishermen include gillnets longline, castnet and driftnets. Sixty percent of beneficiaries and 8% of non-beneficiaries fishermen were using canoe with outboard engines while the rest used canoes with paddles. Beneficiaries earned a higher income (N1, 000 to N9, 000) daily than non-beneficiaries (N1, 000 to N6, 000) daily from sales of fish caught. Major contrainsts to increased catch and income identified include inadequate capital, non- availability of fishing inputs, stealing of fishing gears, lack of access to credit facilities and menace of stump and water hyacinth in the lake. Lastly, recommendation were made for the bank management, government and other lending institutions on how to improve the livelihood of the Artisanal fishermen by increasing the loan usually granted

Poverty alleviation and rural development in Nigeria: a gender perspective

The paper examines the concept of the feminization of poverty and reviews the limited evidence on the extent of poverty among women. It then examines the arguments that poor women can be highly effective change agents for the eradication of poverty. However, all the women may be considered as instruments for eliminating poverty, lack of understanding an appreciation of the impact of their sex roles and of gender roles and stereotypes continue to prevent the realization of this potential. Therefore, the paper moves on to summarize the differences between sex and gender and examines how both women's sexes roles and the imp gender roles and stereotypes lead to the feminization of poverty and exclude women from the participation in development and programmes to eliminate poverty. The paper reviews the major approaches: women in development or WID, gender and development or GAD and extension of GAD known as mainstreaming. Finally, it considers the issue of poverty, women and gender in Nigeria. It also advances a number of recommendations on women and gender poverty and rural development for the consideration of policy-makers in Nigeria

Salvaging the freshwater ecosystems in Nigeria: great threat to sustainable fisheries and aquaculture development

Nigeria, the country of many rivers is also rich in lakes, and wetlands, sustainable and wise use of these inland aquatic ecosystem and water resources has become a matter of widespread and intense concern. Unhealthy freshwater ecosystems and seriously diminishing and unequal availability of quality freshwater call for high quality limnological research and expertise to underpin the enhancement of sustainable fisheries and aquaculture development.In every regard of national health, agriculture and economics, the continued over exploitation and misuse of finite freshwater resources is directly causal to the progressively deteriorating fish production and general standard of living.The integration of basic understanding of inland ecosystems with applied problems and their solutions should be of fundamental concern to all stakeholders in our freshwater resource. This is a basic element in creating an attractive and security ensured economic for investment in fisheries development, including aquaculture. This is the focus of this paper

Resource utilization practices and sustainable development at the Lake Chad basin

The paper examines the resource utilization practices of the Lake Chad in view of the need for sustainable development of the natural resources of the area, which are being recklessly exploited. The issues of obnoxious fishing practices, inappropriate agricultural practices, indiscriminate grazing, reckless fuel-wood harvesting, water pollution etc were discussed. There are clear indications that the current resources utilization practices are pushing the natural resources of the area beyond the limit of their regenerative capacity. This is traceable to institutional weakness and inadequate management strategies at the Lake Chad basin. Suggestions were made towards witnessing a change of attitude to resource use, exploitation and management strategies

Long Run Demand for Energy Services: the Role of Economic and Technological Development

36 p.

Environmental oestrogens and sexual development in fish

This brief paper discusses the assumption that watercourses might be harbouring a chemical(s) affecting the sexual development in fish. Male fish was found with the oestrogen-dependent blood protein, vitellogenin, usually found only in maturing females. The author examines a number of man-made chemicals present in the environment have been found to be oestrogenic. The paper concludes that rivers contain environmental oestrogens that are capable of causing disruptions in the sexual development of fish. Whether or not these environmental oestrogens are causing a widespread disruption in reproduction in wild fish, however, has yet to be determined.