11 resultados para Fishery resources
em Aquatic Commons
Resumo:
A casual study of the hydrological map of Uganda would convince every serious fisherman and fisheater that he is most favoured to be in Uganda. The extent and distribution of the country's aquatic system plus the rich variety of fish species there is promises a fishery potential of considerable magnitude: The open waterways comprised by the Uganda portions of Lakes Victoria, Albert and Edward; and Lakes Kyoga, George plus minor lakes Wamala, Kijanebarora, mutanda, etc. occupy about 15% of the total surface area (91,000 m2; Depart. Land Survey, 1962). Most of the nation's fish supplies are currontly from this source. 1.2. A rich network of permanent and seasonal rivers and streams filling and/or emptying various water systems covers most of Uganda. This aquatic network is associated with a fish fauna whose immense significance as a source of protein is perhaps better appreciated by the local subsistance fisherman and consumer than by the fisheries scientist and manager in this country. Many species of this fish fauna have strong affinities with the open water systems while some are typically riverine. 1.3. Then there are wetlands composed mainly of expanses of swamp, but including some areas of bog. These cover about 2% of the country. While the variety of fish fauna found here is limited by the rather hostile nature of the environment (comparatively de-oxygenated under a canopy of dense stands of emergont vegetation) several specialised fishes e.g. Clarias spp. and Protpterus aethiopicus (Kamongo) occur here. Availability of permanent and seasonal sources of water, well distributed throughout most areas of Uganda, opens up immense potential for a variety of aquaculture practices. However, while active exploitation of much of these fishery resources is currently underway, important questions regarding the magnitudes of the various resource potentials and dynamics, and about suitable levels and modes of exploitation, are yet unanswered. These gaps in knowledge go about the fishery resources of Uganda would hinder formulation of adequate development and management schemes. This short paper examines some of the above problems and suggests some approaches towards balanced oxploitation and management of the fisheries of Uganda.
Resumo:
The year 1968 was yet another year of great success in the exploitation of the fishery resources. The total catch landed was estimated at 108,400 metric tons, worth approximately 77.2 million shillings at the lake shore, and about 220 million shillings in the retail market. This compared favorably with the 1967 catch of 97,000 metric tons, worth approximately 62 million shi11ings on the lake shore and 140 million shillings in the retail market. The 1968 catch exceeded the 1967 catch by 11,400 tons, and also exceeded the expected catch of 105,600 tons in 1971 by 2,800 tons. Most of the fish was consumed within Uganda, where shown a further increase and was estimated at 13 kg. Per head of population.
Resumo:
There is little doubt that the exploitation of the current fisheries of Lakes Victoria and Kyoga requires close monitoring with a view to enforce adherence to prudent management practices. Many indigenous fishes have gradually disappeared from the commercial fishery of both lakes. In the Uganda portion of Lake Victoria for instance Okaronon and Wadanya (in press) have shown that:- 1. The once preponderant haplochromiine taxon ceased to feature in the commercial catches in 1979. 2. The lung-fish (Protopterus aethiopicus) which formerly contributed significantly to the commercial landings had declined to minor species status by the mid 1980s. 3. The catfishes Clarias mossambicus and Bagrus docmac, formerly major fish species, contributed insignificant quantities to the commercial fishery since the early and mid 1980s, respectively. Similar trend have been "reported in the Kenya and Tanzania portions of Lake Victoria (Bwathondi, 1985; Mainga, 1985, Witte and Goudswaard, 1985). On the other hand since their establishment all round the lake in the early to mid 1980s some introduced fishes namely Nile perch (Lates niloticus) and Nile tilapia (Oreochromis niloticus) built up impressive stocks in Lake Victoria (Ssentongo and Welcomme, 1985, Okaronon et al. 1985; Okaronon and Wadanya, in press). Togetther with the native pelagic cyprinid Rastrineobola argentea or Dagaa/Mukene the introduced fishes have contributed unprecidented catches, stimulating vibrant commercial fisheries which have yielded significant social economic benefits to the peoples of the three states riparian to the Lake (Reynolds and Greboval, 1988; Kudhongania et al in press). The impressive landings particularly of the Nile perch and Nile tilapia have also led to rapid industrialisation of fish processing in East Africa mainly for the export market. Fish export has now the potential of a major foreign exchange enterprise in the region.
Resumo:
The present study was undertaken to try and find out why Lates niloticus and Oreochromis nilolicus have managed to co-exist in Lake Victoria (Kenya sector). The study is considered to be of tremendous scientific value not only because Lates has been accused of preying on the cichlid stocks in L.Victoria but also for considering suitable management approaches to maintain viable fishery resources on long-term basis. The results presented are preliminary and the final detailed results will be presented later when the survey will have been accomplished.
Resumo:
Control and management of Uganda fishery resources has been hindered by among other factors the multispecies nature of the resource and the characteristic behaviour of the fishing communities. Fishermen have both genuine and uncompromising attitudes as to why they carry out certain fishing technologies. All fishing activities aim at maximizing the catches or profits while others may fish on a small scale for subsistence. Sensitizing the" fisherfolk on the appropriate fishing technologies, importance of awell regulated fishery exploitation and their participation in control and management of the resource would enhance or lead to increased and sustainable fish production. Socio-economics of fishing technologies were therefore examined using prepared questionnaires and reasons why the fishing communities behave the way they do established.
Resumo:
A review of the historical development of the fishery resources of the Kyoga basin shows that the fishery based on the alien fishes which surplanted the indigenous species in the 1960's and early 1970's has been evolving. The record catches of the 19705 and early 1980's were mainly influenced by increased nutrient supply and enlarged lake volume. The sudden collapse in the fishery particularly of the Nile perch in the mid 1980's was most probably imposed by bad fishing regimes. However, future trends in the fisheries of the Kyoga basin will most likely be controlled by nutrient availability and dynamics as well as by the impact of mans activities in the Kyoga catchment.
Resumo:
Control and management of Uganda fishery resources has been hindered by among other factors the multispecies nature of the resource and the characteristic behaviour of the fishing communities. Fishermen have both genuine and uncompromising attitudes as to why they carry out certain fishing technologies. All fishing activities aim at maximizing the catches or profits while others may fish on a small scale for subsistence. Sensitizing the" fisherfolk on the appropriate fishing technologies. importance of awell regulated fishery exploitation and their participation in control and management of the resource would enhance or lead to increased and sustainable fish production. Socio-economics of fishing technologies were therefore examined using prepared questionnaires and reasons why the fishing communities behave the way they do established.
Resumo:
The fisheries resources of Kyoga basin lakes are of greater socio-Economic significance for the poor rural communities of this area. The lake's fisheries provide the much needed animal protein as well as source of income for the fishers and the rural poor communities. Nationally, Kyoga basin lakes fisheries are economically important in that they contribute 27% of the total national fish production. In addition, more than 15 riparian districts depend on it for food and income. Moreover, fish from lakes Kyoga and Kwania playa major role in the regional export commodity trade earning the country foreign exchange. The perception that heavy exploitation of inland fishery resources threatens a loss of socio-economic benefits to local communities and their governments has prompted the new ways of management.
Resumo:
Lake Nakivali is one of the four small lakes that form what is known as the Koki lakes system. It is 14 km long, 6 km wide, 26 km2 in area and has maximum depth of 3.5 m at high water level. The lake is located in a lake-swamp complex with River Rwizi as the principle inflow, and a number of peripheral lakes among which are four major ones, i.e. Lakes Nakivali, Mburo, Kachira, and Kijanebalola. The survey therefore established that Lake Nakivali is a healthy ecosystem capable of sustaining fisheries production. While stock enhancement through restocking with fry could boost fish stocks, especially of the Nile tilapia, effective management measures that allow natural regeneration of stocks of indigenous fish species is paramount. This may require closed fishing seasons and control of fishing effort. Tank aquaculture is a viable option for increasing fish production and Ngege (O. niloticus) and Male (C. gariepinus) are candidate fish species for fish farming.
Resumo:
Over the years, degradation of the lakeshore resources has been going on due to human induced activities. Human activities notably house construction, fish smoking, boat construction and cooking at the landings impact the tree and forest cover along the lakeshore and Islands. The survey was conducted in ten districts surrounding Lake Victoria and the landings sampled were selected with the help of the District Fisheries Officers. Data was obtained from selected fishermen and Key informants at these landing sites. The study examined the extent of knowledge on importance, utilization, threats and conservation of trees/forests at the landings. Results showed that the fishers (98%) were aware of the benefits derived from the trees/forests. According to the respondents, the most commonly used tree species for boat construction were Mvule (40%), Mkibu (20%), Musizi (17%) and Mpewere (11 %). This was mainly because these trees were durable. For house construction, Nsambya (25%), Musizi (24%) and other materials (12%) were the most commonly used. For other activities like fish smoking and cooking at the landing, the Fisherfolk used any type of tree species readily available at the landings. As regards the status of the trees at the landings, most of the respondents (72%) J agreed that due to some fishery related activities some tree species had reduced more than others in the vicinity of most landings. Most respondents said that the, most reduced tree species around the landings were Mvule (36%) and Musizi (22%). Among the fishery related activities that had a significant impact on the trees/forests, construction of houses (44%) and boats (22%) emerged uppermost. Other activities such as fish smoking (14%) and cooking (12%) had the least impact on trees/forests. Generally, there was extensive reduction of trees at the landings. Therefore there was need to regulate cutting of trees and to have specific programmes targeting afforestation at and around fish landings.
Resumo:
The major dangers facing the resources of the Great Lakes of Africa include over exploitation, falling species diversity, accumulating pollution, and a probable decline in fishery productivity. These dangers may be viewed as accentuated by: i) Inadequate scientific knowledge on the exploited resources ii) Reluctance to apply even the limited scientific information available, by fishery administrators iii) Constant increase in the demand for fish and other aquatic resources. iv) Lack of commitment to active collaboration and co-operation by riparian states regarding development and management of the shared resources. This paper discusses the above factors in relation to the dangerous trends facing the resources of the Great Lakes of Africa. The discussion is intended to contribute to the promotion of rational and sustainable utilisation of the aquatic resources of these lakes.