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  • A Schoolteacher's Guide to Marine Environmental Education in the Eastern African Region.

    Francis, J.; Mwinuka, S.; Richmond, M. (United Nations Environment Programme (UNEP) and the United Nations Food and Agriculture Organisation (FAO), 1999)
    The main objective of this book is to provide teachers of primary and secondary schools in the western Indian Ocean (WIO) region with a basic textbook that will allow them to introduce environmental components in the classroom as well as in outdoor activities. More specifically, it aims at supplying teachers, particularly those with a limited background in marine science, with an overview of the coastal and marine environment and its important ecosystems. Although some of the marine and coastal issues covered in this book already exist in the curricula of other subjects, such as science, geography and agriculture, their coverage in standard textbooks' is either very limited or too detailed and specialised. Therefore, this book can be used individually or together with other available information on the topics concerned, to complement curriculum objectives of the different subjects. The book comprises seven chapters, namely: (1) Environment and Ecology; (2) Oceans and Seas; (3) The Seashore; (4) Mangrove Forests; (5) Coral Reefs; (6) Coastal Pollution and (7) Coastal Resource Management. In the introduction of each of these chapters a section on 'Specific Objectives' is included to act as a guide for teachers to help determine their success at conveying the 'Background Information' to their students. To assist teachers measure changes in their students' attitudes towards the coastal environment in which they live, each chapter also includes a section on 'Skills and Behaviour to be Reinforced' which serves as a reminder of the overall goal of attitude change. Changing attitudes is the main aim of this book, and to assist in this process teachers are encouraged to develop classroom and outdoor activities which include the participation of the students in order to help them acquire new skills. A section on 'teaching and learning strategies' is included at the end of each chapter, listing a few examples of such activities. Teachers are free to decide how they wish to incorporate and disseminate the information provided. They are encouraged to develop their own individual presentation style and modify the teaching and learning strategies as they see fit to their situation and the experience of their students.
  • Economic Valuation of Kenya’s Mangrove Forest: A Case Study of Mida Creek; Kilifi, Kenya

    Mwangi, John Muiyuro (Abdus Salam International Centre for Theoretical Physics, 2004)
    The purpose of this paper is to suggest and then illustrate an approach to contingent valuation of renewable natural Resources that we feel has considerable theoretical and practical appeal. Valuation of a Mangrove forest is linked to the community’s Willingness To Pay (WTP) for it’s conservation. A bid curve is estimated to investigate the determinants of WTP bids. Special focus has been placed on the negative effect associated with deforestation of mangrove forests on the livelihood of the Kenyan rural population with consequent implications on the urban communities. The study also investigates the relationship between the recent trend in coastal area urbanization increase and mangrove deforestation.
  • Artisanal fishing on the Kenya coast: what are the impacts?

    Samoilys, Melita; Osuka, Kennedy; Waweru, George; Obura, David (2011)
    Kenya's population has more than doubled in 30 years: from 16 million in the late 1970s it is set to reach 55 million by 2050. Finite fish populations cannot sustain this demographic pressure. In this context we looked at the effects of artisanal fishing gears used by local fishermen in Kenya to evaluate their impacts on coastal fishes and review management practices. There are 12 different gears used by artisanal fishermen, five of which are widespread and commonly used. We collated data from 20 published studies and our own to examine long term trends and ecological impacts of the five commonly used gears. CPUE has dropped dramatically since the 1980s from 28 kg fish /fisher/day to 3 kg/fisher/day. However, from the mid 1990s to 2006 CPUE has remained relatively stable and consistently so across the different gears, an indication of sustainable levels of fishing. Catch rates differed consistently by gear with spear gun catch rates always the highest and beach seines catch rates the lowest. These gears are both illegal. The differences are useful in enforcing or revising regulations. For example beach seine crews could be advised to use basket traps or handlines if they want more income. Young men tend to reject the traditional basket trap, but its catch rates were consistently higher than gillnets. An average juvenile retention rate of 50.1 % was reported across all gears with the highest recorded by the illegal beach seine (68%) and the lowest by spearguns (38%). We found few reasons to support the illegal status of spearguns: the lowest juvenile retention rates, no by-catch and one of the most affordable gears. Although CPUE has remained steady since 1999, diversity in catch composition has declined. We discuss the implications of these fishing effects on the future of Kenya's coastal fish populations.
  • Kasa News: a newsletter of the Kenya Sea Turtle Conservation Committee (KESCOM) 10th Edition, 2004.

    Kenya Sea Turtle Conservation Committee (KESCOM) (Kenya Sea Turtle Conservation Committee (KESCOM), 2004)
    The newsletter describes various news articles, events, activities and information of relevance to the Kenya Sea Turtle Conservation Committee (KESCOM).
  • Cruise Report R/V ”Dr. Fridtjof Nansen” Survey of the Abundance and Distribution of Fish Resources off Kenya 7-15 December 1982

    Iversen, Svein A. (Institute of Marine Research, 1982)
    Objectives for the survey were as follows: (1) Acoustic/fish survey whole shelf (200 m); (2) Detailed study of fish distribution Malindi Bank; (3) Trap/longline fishing in various localities including Kenya Bank; (4) Hydrographic sections.
  • Offshore Trawling Survey Kenya: Project Findings and Recommendations -- FI:DP/KEN/74/023 Terminal Report.

    Food and Agriculture Organization of the United Nations (Food and Agriculture Organization of the United Nations, 1983)
    The survey described in this project terminal report was planned to provide detailed and reliable data on the demersal resources in the waters outside the reef area, to be used eventually for a pre-investment study for development of an offshore (trawl) fishery.
  • Summary of group and plenary discussions Report of plenary discussion on groundwater outflow model

    Kamermans, Pauline; Hemminga, Marten (1998)
    A special session was devoted to the refinement and validation of the groundwater outflow model. The following topics were discussed.
  • Kenya-Belgium Project. Report on the Physiological Respiratory Adaptations of Oreochromis niloticus L.

    O'Omolo, Samson; Kidi-Okoth, Brigitte (Antwerp State University, 1986)
    The main objective of this work was to investigate physiological respiratory adaptations of Oreochromis niloticus to hypoxia under different temperature conditions. This African cichlid is widely distributed around the world where temperature is suitable for its growth and reproduction. In many countries it was introduced for vegetation control, pond culture, recreational and commercial fishing, because of its excellent aquaculture potential, fast growth, omnivorous feeding habit and tolerance to low water quality. Like many other cichlids it is also known for its tolerance to temperature variations. However, from the physiological, ecological and economical points of view, such important aspects like rate of thermal acclimation temperature acclimation, critical temperature and oxygen pressure still remain to be elucidated.
  • A brief report on a survey of the fish and fisheries of the Tana river, with special reference to the probable effects of the proposed barrages.

    Mann, M.J. (East African Freshwater Fisheries Research Organization, 1969)
    The construction of several barrages, in order to develop the hydroelectric and irrigation potential of the Tana river, has been proposed and the probable effects of these developments upon the fish and fisheries of the area has been investigated. Briefly in the highest reaches the sport fishery will be unaffected, in the, middle reaches the sparse subsistence fisheries will be only slightly inconvenienced but in the terminal reaches of the river the subsistence and commercial fishing enterprises are expected to be seriously reduced by the progressive re-regulation of river-flow. However each new dam will support a new and productive reservoir fishery and with proper development the annual yield of fish from the Tana basin is expected to increase considerably.
  • Tudor Creek, Mombasa: The Early Life History Stages of Fish and Prawns 1985. Overseas Development Administration, Research Project R3888.

    Grove, S.J.; Little, M.C.; Reay, P.J. (Plymouth Polytechnic, 1986)
    The project was based at KMFRI headquarters in Mombasa, with Tudor Creek (a fully saline area of mangroves, mud and open water) as the study area. Sampling mainly involved the use of plankton nets and fine-meshed beach seines, in all months from February to November 1985. Sampling frequencies of hours, days and weeks were also employed in order to cover the diel, circatidal, semilunar and lunar cycles. From the samples, prawn post-larvae, fish eggs and larvae, and juvenile fish and prawns were sorted, identified as far as possible, and counted in order to provide data on their occurrence, distribution and abundance. Records of temperature, and some other abiotic parameters, were also maintained. 'l'he fish and prawn fauna of Tudor Creek, is described from the results of the seine-net sampling and is found to include 6 species of penaeid prawn and 135 species (49 families) of teleost fish; additional families were recorded only as larval stages in the plankton. Many of the fish occurred as juveniles, but very few of these were species commercially exploited on nearby reefs and trawling grounds. Differences have been found between the creek mouth and inner creek in terms of both planktonic and juvenile stages, and are associated with a gradient of decreasing depth and dissolved oxygen concentration, and increasing temperature and turbidity from the mouth inwards. One of the' most conspicuous trends has been the decrease in fish egg density and diversity along this gradient, which suggests that while the creek can be regarded as a fish and prawn nursery area, it is not an important spawning ground, at least for pelagic spawners. The existence of the gradient also results in tide-related changes in egg-density which are probably lest explained in relation to the tidal incursion of egg-rich coastal water into the creek rather than to tidal spawning cycles of adult fish. The latter have not been discounted, however, and may emerge from further analysis of data from individual taxa. No clear indication of general systematic seasonal changes in either the planktonic or Juvenile stages were found, but the lowest catch-rates of some species of juveniles occurred during the early part of the SE Monsoon (April/July). Again further analysis of data from individual taxa of both planktonic and juvenile stages, and of the size-frequency data collected; may reveal clearer evidence of seasonal periodicity. The results are discussed in relation to the literature available on similar ecosystems in other tropical areas, and in relation to the major problems encountered in carrying out the work. It is concluded that much has still to be learned about the role of mangrove creeks as nursery areas, and also that this role is important in the context of future fisheries management and environmental monitoring with this application in mind, it is recommended that future work should concentrate on the post-settlement juvenile stages rather than on the planktonic stages, and an argument is presented to support this view.
  • The Biology of Trout in Kenya Colony.

    Van Someren, Vernon D. (River Research Centre, 1950)
    Apart from Copley's papers (1940 a, b, 1947, 1950), there have been no scientific observations made on trout biology in East Africa, though van Someren has also published a few preliminary observations (1946). Trout were first introduced into Kenya Colony in 1905, and there are now many miles of trout water available in the Colony; the history of their introduction has been described by Copley (1938, 1940 a and b). Management of these trout waters has been largely empirical and remarkably successful, though the need has now been recognised to support such management policies by biological data. Because such data are largely lacking, the work at the Research Centre, which has gradually increased in scope as facilities became available, has been directed mainly towards the collection and assessment of facts on the natural history of our exotic trout in all aspects. Two and a half year's work has seen the amassing of a very large quantity of such factual data, and the results are presented herewith. The reader will find this first account of trout biology purely descriptive and analytical; very few experimental results are described, and there are only occasional references to aspects and policies of fishery management. Proposals for the later can only be based on the scientific data now being made available, and will follow naturally as results become known and confirmed by experimental procedure. Thus in time will the rivers yield the fullest of which they are capable.
  • The Mangroves of Kenya: general information. Compiled for Netherlands Wetlands Conservation and Training Programme, 1996.

    Martens, Els (Kenya Wildlife Service, 1996)
    The report contains general information on mangroves in Kenya with the following main topics: Mangrove ecology, Mangrove distribution, Mangrove vegetation, Mangrove associated flora, Mangrove fauna, Values and utilization, threats. Interactions between mangroves, seagrasses & coral reefs. Main problems related to mangrove management and Conservation. Managing mangroves to insure their survival.
  • National report: Kenya

    Ruwa, R.K. (1992)
    The report actually reflect the effort made by Kenya as a country to accomplish many research works namely in collaboration with the COMAR regional programme of UNESCO.
  • Notes on the mangrove swamps of Kenya.

    Graham, R.M. (1929)
    Journal of the East Africa Natural History Society and National Museum
    It is estimated that the Mangrove Swamps in Kenya cover an area of about 180 squares miles. All have been gazetted as forest reserves. Since only four creek systems have been surveyed, it is obvious that the area given is only approximate, but the composition of the gazetted areas does not vary very much. Judging by the four swamps that have been surveyed, it seems probably that only about two-thirds of the total area can be classed us merchantable forest. The remainder consists of scrub mchu, liIana and undersized mkandaa. Of the merchantable forest, probably 70% consists of well-grown mkoko, with scattered muia and mkandaa, and 30% of badly-shaped mkandaa which, however, finds a market as fuel.
  • A Land(Scape) Ecological Survey of the Mangrove Resource of Kenya - Draft Report. [incomplete?]

    Ferguson, Wankja (Forest Department, 1993)
    In order to enable the formulation of a management plan for the mangrove forest as well as the future monitoring of the resource a mapping of the entire mangrove area was required. The present survey has mapped the mangrove forest through the landscape ecological method. This method entails a holistic approach to the mapping the resource, it deals with the inter-relationship between man and his open and built up landscapes, allowing the establishment of the important links between the resource and its environment, be this its natural environment such as the climate, terrain, soil, etc. and the human impact on the resource. This methodology was preferred above the traditional forest survey methodology, since it allows to gather and compile the necessary background material to facilitate the tools for the understanding and management of human ecosystems. Several important concepts come up when considering the understanding and management of human ecosystems, the carrying capacity or sustainable yield considers the optimum human impact that a particular environment can support without leading to its degradation and although the term farming system is not common in forestry, it could be applied to the resource converting it into forestry system, whereby the forestry system would than be seen as the interwoven relationship of land, plants, animals, technology and the social, cultural and traditional background of the forest users (cutters, licensees, forest personnel). This survey attempts to deliver the necessary information for the purpose of the formulation of a holistic management plan. It will indicate as well where the information is considered not sufficient and where estimates have been •made. It recommends to gather this information and put research programmes in place the soonest possible. Even though the information at present is not complete, the planning of a management plan is seen as dynamic, updatable at any time. On basis of the present information surely actions can be taken to safeguard the resource for future use and existence.
  • Report on Kenya Fisheries 1968.

    Kenya Fisheries Department (Fisheries Department, 1968)
    There was a further increase in production of fish and other marine products by Kenya fishing industry in 1968.
  • Preliminary Survey of the Pelagic Fishes of East Africa.

    Williams, F. (Her Majesty's Stationary Office, 1956)
    The scope of the survey is defined. A short description is given of the hydrographic and climatic conditions of the East African coastal region. A full description is made of the gear used in multiple trolling from M.F.V. "Research". The efficiency and limitations of the gear are discussed, with suggestions for improvements in the method. Most effective trolling speed was 5-6 knots. The twenty-eight species of fish taken by trolling are fully described. The catch, seasonal abundance and distribution of the pelagic fishes are discussed. Some species - Caranx, Sphyrcena, Aprion and Plectropoma appear to be present throughout the year. They are more numerous during the N.E. monsoon when the gonads are in the spawning condition. Coryphcena hippurus makes an inshore spawning migration from January to June. Due to migrations other pelagics such as the Scombrids show a marked seasonal abundance, but little is known as yet of the reasons for the migrations. Shoals of tunny-like Scombrids have been seen in large numbers but fish were not taken from them by trolling. Monthly details of the catch of fishes are tabulated for each section of the coast. The average catch rate for the whole of the survey was 1•14Ibs./line/hour. The monsoon conditions have a direct bearing on the productivity of the fishery, especially in the S.E. monsoon. Fish are almost entirely restricted to within the 100 fin. line. Largest numbers are taken where a shallow shelf extends out from the fringing reef or over the shallow off-shore banks. Reasons for this distribution are advanced. It is concluded that multiple trolling alone by a fishing boat the size of "Research',' would not be commercially profitable. However the expansion of the native fishery for pelagic fishes is advocated. Two possible methods of development by using trolling are given. Suggestions are made for the capture of tunny-like shoals by means of a purse seine or the live bait technique, together with the use of deep long lines for tunny and gill nets for the capture of the smaller shoaling Carangids and Scomberomorids. The future biological investigations to be carried on the pelagic fishes are discussed.
  • Report on Kenya Fisheries 1967.

    Kenya Fisheries Department (Fisheries Department, 1967)
    The Report on Kenya Fisheries 1967 summarizes the activities that occurred within the Fisheries Industry in Kenya.
  • An Investigation of the Biology and Culture of an East African Oyster Crassostrce cucullata.

    Van Someren, V.D.; Whitehead, P.J. (Her Majesty's Stationary Office, 1961)
    CrassostrtZa cucullata (Born) is the most important edible oyster of the East African coast, and is .a purely littoral species occurring intertidally on open reefs, mangrove roots and creek rock exposures. Heavy commercial exploitation ofoyster beds on the Kenya coast has led to almost complete destruction of these beds, and in all areas the rate of natural regeneration and recovery of beds appears practically negligible, or at the best, an extremely slow process. Exploitation of beds, hitherto unlicensed, is now strictly controlled by Government. A survey of the biology and ecology ofoysters was carried out between September 1953 and August 1954, with further brief visits in October 1954 and September 1956, with particular reference to conditions in Mida Creek, one ofthe largest natural beds of oysters on mangroves. Here two forms of oyster occur; one, a spiked form growing on mangrove roots at higher tidal levels, and the other a flat form, growing at the lower levels. These appear to be distinct species, the latter being recognizable as C. cucullata; no attempt 4as been made to determine the identity ofthe former, which is referred to as Species A. The tidal and certain physico-chemical conditions in Mida are described in detail, these being different from those of the open shore, owing to the geographical formation of the Creek. The particular differences in each oyster zone are well marked. The oysters themselves are confined only to the eastern fringes of the mangrove forests, a spatial distribution which limits their abundance, and which may be due to the habit ofthe settling spat. They occur also on old reef rock expanses, and are phoretic on the abundant mollusc Terebralia palustris Brug. Zonation on the mangrove roots is distinct, and bears a strict relation to tidal levels. Temperatures, salinity and rainfall figures were noted, and their seasonal and local variations are described. Weekly dissections of adult oysters were made to determine spawning rhythms. While spent oysters may be found in armost any week ofthe year, and a low level ofspawning is continuous, nevertheless spawning sho~s two maximal periods coinciding with the onset of the rainy seasons in the year. The environmental factors related to spawning are complex, and it is suggested that (a) maximal water temperatures oYer 85"F (29'S°C), (b) the immediate onset of rain and (c) a fall in salinity are jointly responsihle for major spawning activity. While natural spat is very rare on all Kenya oyster beds, nevertheless a variety of spat collecting devices tried at Mida showed that spat would settle readily on Mangalore tile collectors, and shell culch strung on wires. The importance of cleanliness of spat collectors is not yet fully established for Kenya conditions and further trials are required both in this connection and that of the most suitable method in which to arrange the collector and the best type of collector. Itis, however, certain that some form of cultural method, using spat collectors, is fully practicable. While spat may settle at almost any time of the year, the heaviest spatfalls occurred at the beginning of, and during, the rainy seasons of November/December and April/May, the latter season providing maximal spatfall. The duration of free swimming larval life is not, however, known. All spat collected settled within a few inches ofground level, and appeared to be that of C. cuculla!a. Under natural conditions spatfall is fractional only, and the evidence suggests that the spat settle by preference on hard surfaces, mangrove bark being a second "choice". The conditions influencing settlement of spat are discussed. Growth of spat collected at Mida is very fast, averaging about 0·6 em a month; at only seven months the young oysters have reached the average adult length, but not thickness; thickness is added during the second year of life, and artificially grown oysters reach marketable size in about 2! to 3 years. Spat from elsewhere, grown at Mida, does not grow so fast, nor does Mida spat at levels above their normal tidal zone. Growth or survival of spat under pennanent submerged conditions is not known• Natural mortality of spat is not particularly heavy, nor apparently are there many serious natural predators. The growth of spat may vary according to season, but once adult, the oysters apparently cease to grow. Size at first maturity is not known. The preliminary results indicate that artificial culture of these Kenya C. cucul/ata oysters on shell culch strung on wires, and on tile collectors, would be practicable and economic, and indeed essential if exploitation is to continue at its present level. Possible cultural methods are discussed, and in places such as Mida or Ngomeni reef, there are large potentially productive areas which could be utilised for such culture.
  • Report to the Government of Kenya on the Sea Fisheries of Kenya June-July 1958. Based on the work of J.A. Crutchfield (FAO Technical Assistance Fishery Expert).

    Food and Agriculture Organization, 1958
    There is a widespread feeling among government and business officials that expansion of the Kenya coast fisheries is impeded by an inadequate and restrictive marketing structure. Various plans for improvement of the industry have been put forward by the trade -and by the Game Department's Fisheries Division, but all have been subject to vigorous objections from one or more groups concerned. The Kenya government therefore requested the Food and Agriculture Organization to assign a qualified person to survey the industry and to recommend measures for improve the marketing of sea fish. This request was subsequently broadened to include an appraisal of the need for a loan fund for Arab, African and Bajune soa fishermen.

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