Some experiments on commercial pond fish culture in the tidal mangrove area of Niger delta of Nigeria

A pilot fish culture project was initiated by Shell Petroleum Development Company of Nigeria Limited in 1981 with specific aims and objectives. Site selection, survey, pond construction method and fish production with regards to experiences gathered and gained, problems and solutions so far obtained are discussed. Trials of freshwater fish species to check their adaptability to brackishwater ponds were carried out and the promising results of the growth rate of these species when compared with the traditional local brackishwater species selected for culture are reported. The extension programme so far carried out is briefly described

The variation of water quality in the outdoor concrete tank and earthen pond

The paper reports on the study carried out at the Federal College of Freshwater Fisheries and Technology (Nigeria) and the Hatchery Complex in 1997. The physico-chemical parameters of an earthen fish pond and concrete tank were analysed. The abundance and distribution of phytoplankton and zooplankton were recorded. A total of eight species of phytoplankton were observed. These species can be classified as Chlorophyceae (green algae), Bacillariophyceae (diatom algae) and Cyanophyta (blue-green algae). Eight zooplankton species were observed in the pond and 6 in the tank. Moina was observed and recorded as the most abundant cladoceran species in the tank

The hydrology of a small fish pond at the University of Agriculture, Makurdi Experimental Fish Farm

The monthly and seasonal water requirements of a small fish pond (0.068ha; maximum capacity of 613.83m super(3)) at the University of Agriculture, Makurdi Fish Farm (Benue, Nigeria) were determined during the period of February to August 1996. The sources of water for the pond were rainfall, (103.4cm), run-off (6.3cm) and regulated inflow (95.0cm). The water loss for the period were Evapotranspiration, (106.74cm), Seepage (71.64cm) and regulated discharge (25.00cm). Evapotranspiration was identified as the main source of water loss while rainfall was the major source of water gain. The mean monthly water deficit was 24.56~c11.43cm while the mean monthly surplus was 9.84~c8.05cm. The quantity of water required to maintain the optimal water level in the pond was 474.00m super(3). Preliminary water budget of the study area showed that rainfed aquaculture can be effectively carried out at Makurdi during the months of June to October with supplementary inflows during the dry season months

Homestead fish pond and the environment in Nigeria

Homestead fish culture is a recent innovation for mass production of fish at backyard in Nigeria. The processes of pond construction often have resulted in soil disturbances, vegetation losses, and creation of new aquatic environment. The paper discusses homestead ponds in Nigeria, their potential impact on the environment which includes erosion, over flooding, pest and disease, accident risk, undesired fossil fuel production, vegetation destruction and fish genetic conservation, strategies for environmental management in relation to pond construction are suggested

Effect of fish meal in formulated diet on the growth of Heterotis niloticus in semi-intensive pond culture system

The aim of the investigation is to know the percentage of fish meal required to support the best growth of Heterotis niloticus in a semi intensive pond culture system. To achieve this, feed was formulated with equal percentages of blood meal, and corn meal and varying levels of fish meal. The experiment was in four treatments. Results showed that the mean weight gained was directly proportional to the quantity of fish meal made available to the fish fence 31.58g, 33.79g, 45.15g and 51.24g were recorded for treatments I, II, III and IV respectively. Result from this study when compared with previous works, shows that size of the water body to a greater extent affects the growth. The availability of fish meal in the feed made it more acceptable to the fish and hence a commensurate conversion in to flesh. The analysis of variance showed that there is significant difference in the growth performance in the treatments

Length-weight relationship and organ indices of pond raised and wild population of C. gariepinus (Burchell 1822) pisces-Claridae

Samples of C. gariepinus collected from the wild and cultured populations in Plateau and Niger States of Nigeria were analyzed for length-weight relationship and organ indices (Gonadosomatic index (GSI), hepatosomatic index (HSI), renalsomatic index (RSI) and somatic fat deposit index (PDI). High correlation and linear relationship between body length and body weight was observed in all sample population (P<0.05). A significant difference was observed between the GSI of males and females of both wild and cultured population and also between females of the wild and cultured population,(P < 0.05).There was no significant difference in HSI, CSI RSI and PDI of all the sample populations (P < 0.05).The importance of length-weight relationship and organ indices in fish production are discussed

Some potential occupational and environmental hazards associated with fish pond production in Nigeria

The paper highlights the concept of information and the significance of environmental and occupational hazards associated with pond fish production in Nigeria and discuss the possible options for the ways forward. The major raw material used in fish production system is the organic manure (cow dung, poultry droppings, porcine manure etc) that serves as substrate for heterotrophic production of bacteria and protozoa, which act as food for zooplankton and the fish. The pathogenic organisms (viruses, bacteria, protozoa's, and parasites), are noted for the potential hazard to the fish handlers and consumers. Nine species from seven genera of bacteria associated with fish diseases are found to have association with diseases of human such as typhoid fever, bacillary dysentery and other gastrointestinal tract related problems. Also the environmental contaminants in pond fish production become important because of its significance to consumers' acceptance of the fish products

Pond action: Promoting the conservation of ponds in Britain

Pond Action is an independent freshwater conservation project which was started in 1987. It is based in the School of Biological and Molecular Sciences in Oxford Polytechnic and has five full-time staff with two senior advisors. The main aim of Pond Action's work has been to promote the conservation of ponds by creating a sound, scientific basis for pond conservation. An essential aspect of this work is the need to make the results of scientific work available and understandable to everybody concerned with pond conservation.

Rapid changes in the vegetation of a shallow pond in Epping Forest, related to recent droughts

Over much of Britain, 1995 and 1996 have been perceived as drought years. To evaluate the impact that local climatic conditions are having upon successional changes in higher vegetation (macrophytes), Speakmans Pond in Epping Forest was surveyed and mapped in 1996. The results are related to previous vegetation surveys carried out in 1989 and 1991. In 1989 the dominant marginal vegetation was floating sweet-grass Glyceria fluitans, which also covered a major part of the main body of the pond. Other abundant species included soft rush Juncus effusus, reed mace Typha latifolia and yellow flag Iris pseudocorus. A small (central) area of open water contained bladderwort Utricularia vulgaris and white water-lily Nymphaea alba. A similar plant coverage was found in 1991, with a dominance of floating sweet-grass along the shallow eastern edge. A marked change in the pond was found during the 1996 survey of vegetation in July, when the pool was dry. The major plant cover now consisted of creeping bent Agrostis stolonifera, with isolated clumps of Yorkshire fog Holcus lanatus around the edges; both are terrestrial grasses found on land surrounding the pond. Rushes (Juncus) had increased their distribution round the margins of the pond, and the patch of yellow flag noted in 1989 and 1991 was not found in 1996. The deeper trenches were also dry, but a small patch of white water-lily remained adjacent to one of the trenches.

"Rapid and dramatic changes in vegetation" of a small pond on Holy Island (Northumbria): Chaotic dynamics?

This note describes changes to the relative extent of four structurally dominant submerged macrophytes in a pond on Holy Island National Nature Reserve, Northumbria, between 1991 and 1998. The estimated extent of the four submerged macrophytes and bare substratum between 1991 and 1998 showed dramatic changes with no obvious pattern or periodicity, as well as no identifiable natural or anthropogenic causes. Chaotic variation may be an important character of submerged pond plant populations, so that surveys taken in a single year may give an unreliable picture of plant populations.

On the occurrence of Pithophora oedogonia (Mont.) Wittr. var. polyspora Rendle et West fil (Cladophoraceae) in the pond of the Wroclaw Botanical Garden [Translation from: Fragmenta Floristica et Geobotanica 22 255-260, 1976]

Species of Pithophora occasionally appear in Europe and are associated mostly with the tropical, higher water plants, cultivated in numerous botanical gardens. In June 1973 pale green, branched threads were discovered in the pond of the Wroclaw Botanical Garden, amongst filaments of Spirogyra crassa (Kutz.) Czurda emend. and Cladophora glomerata (L.) Kutz. floating on the water surface. They were maintained for several weeks in crude cultures and produced numerous, dark akinetes tightly packed with reserve material. This collected material was found to be a member of the family Pithophora, Wittr. Further examinations identified the material as Pithophora oedogonia. The findings point out that it is probable, that species of Pithophora Wittr. can become acclimatized in Europe, primarily in ponds of botanical gardens, where consequently they are able to tangle easily with higher tropical plants.

Living on the hyphen: diaspora, identity and memory in Jamaica Kincaids Annie John / Lucy and Esmeralda Santiagos When I was Puerto Rican / Almost a woman

Esta dissertação tem por objetivo investigar o desenvolvimento de identidades de sujeitos diaspóricos em formas de narrativas nas quais a memória tem um papel crucial. As autobiografias e os memoirs têm despertado a curiosidade de muitas pessoas interessadas nos processos de construção de identidade de indivíduos que vivem em realidades singulares e nos relatos que dão sobre suas próprias vidas. Assim, o crescente interesse em diásporas e nos decorrentes deslocamentos fragmentários, provocados pelo distanciamento de raízes individuais e pelo contato com diferentes códigos culturais, poderiam legitimar as narrativas autobiográficas como maneiras estratégicas de sintetizar os nichos de identificação de autores e autoras que experimentaram uma ruptura diaspórica. Desta forma, ao analisar estes tipos de narrativas, deve-se estar atento às especificidades de algumas escritoras que passaram por processos diaspóricos e a como elas recorreram as suas memórias pessoais para, em termos literários, expressar suas subjetividades. Considerando todas essas idéias, tenciono usar Annie John e Lucy, de Jamaica Kincaid e When I Was Puero Rican e Almost a Woman, de Esmeralda Santiago como fontes de análise e amostras do desenvolvimento de identidades diaspóricas em narrativas autobiográficas

Diasporization and family relations in Nella Larsens Quicksand and Jamaica Kincaids Lucy: the construction of female identity

O principal objetivo desta dissertação é investigar e analisar como os movimentos diaspóricos e as relações familiares exercem influência na construção das identidades das mulheres em Quicksand, de Nella Larsen, e Lucy, de Jamaica Kincaid. As questões a que pretendo responder são: Como as personagens principais, Helga Crane e Lucy, lidam com as diferentes culturas que encontram nas suas trajetórias ? ; Como essas diferentes culturas lidam com essas mesmas personagens?; e Como o encontro entre essas diferentes culturas e as relações familiares são descritos e influenciam na construção da identidade feminina nessas obras?. Minha hipótese é que encontraremos nas obras selecionadas duas jornadas, portadoras tanto de aspectos comuns quanto distintos, que começam com o desejo das personagens principais de escapar da opressão patriarcal. Isto é, Helga Crane e Lucy passam por um período de muitas descobertas sobre elas mesmas e as sociedades com que têm que lidar, o que determina dois produtos diferentes: a construção das identidades híbridas de Lucy, em meio a sua solidão, na obra de Kincaid, e a construção e o sufocamento das identidades de Helga pela religião, o patriarcado e as relações familiares, na obra de Larsen

Remote Sensing and Field Assessment of Tsunami Effects on Coastal Pond Aquaculture in Northern Sumatra

An attempt was made to conduct spatial assessment of the pattern and extent of damage to coastal aquaculture ponds along the east coast of Aceh province in Sumatra, Indonesia, resulting from the tsunami event of 26 December 2004. High-resolution satellite imagery, i.e., SPOT-5 multispectral scenes covering the 700 km stretch of the coast, acquired before and after the tsunami, were digitally enhanced and visually interpreted to delineate pockets of aquaculture ponds that were discerned to be damaged and relatively intact. Field checks were conducted at 87 sites in the four eastern coastal districts. The results indicate that SPOT-5 multispectral imagery was minimally sufficient to detect areas of damaged and relatively intact aquaculture ponds, but the 10-m spatial resolution poses limitations to evaluating the extent of pond damage. Nevertheless, the 60 km swath of the imagery makes it reasonably affordable for large-area assessment to identify pockets of severe damage for targeting more detailed assessments. The image maps produced from a mosaic of the SPOT-5 scenes can also serve as base maps for spatial planning in the challenging task of reconstruction and rehabilitation of the disrupted livelihoods of the coastal communities.