60 resultados para All-sky-survey

em Aquatic Commons


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This technical memorandum documents the design, implementation, data preparation, and descriptive results for the 2006 Annual Economic Survey of Federal Gulf Shrimp Permit Holders. The data collection was designed by the NOAA Fisheries Southeast Fisheries Science Center Social Science Research Group to track the financial and economic status and performance by vessels holding a federal moratorium permit for harvesting shrimp in the Gulf of Mexico. A two page, self-administered mail survey collected total annual costs broken out into seven categories and auxiliary economic data. In May 2007, 580 vessels were randomly selected, stratified by state, from a preliminary population of 1,709 vessels with federal permits to shrimp in offshore waters of the Gulf of Mexico. The survey was implemented during the rest of 2007. After many reminder and verification phone calls, 509 surveys were deemed complete, for an ineligibility-adjusted response rate of 90.7%. The linking of each individual vessel’s cost data to its revenue data from a different data collection was imperfect, and hence the final number of observations used in the analyses is 484. Based on various measures and tests of validity throughout the technical memorandum, the quality of the data is high. The results are presented in a standardized table format, linking vessel characteristics and operations to simple balance sheet, cash flow, and income statements. In the text, results are discussed for the total fleet, the Gulf shrimp fleet, the active Gulf shrimp fleet, and the inactive Gulf shrimp fleet. Additional results for shrimp vessels grouped by state, by vessel characteristics, by landings volume, and by ownership structure are available in the appendices. The general conclusion of this report is that the financial and economic situation is bleak for the average vessels in most of the categories that were evaluated. With few exceptions, cash flow for the average vessel is positive while the net revenue from operations and the “profit” are negative. With negative net revenue from operations, the economic return for average shrimp vessels is less than zero. Only with the help of government payments does the average owner just about break even. In the short-term, this will discourage any new investments in the industry. The financial situation in 2006, especially if it endures over multiple years, also is economically unsustainable for the average established business. Vessels in the active and inactive Gulf shrimp fleet are, on average, 69 feet long, weigh 105 gross tons, are powered by 505 hp motor(s), and are 23 years old. Three-quarters of the vessels have steel hulls and 59% use a freezer for refrigeration. The average market value of these vessels was $175,149 in 2006, about a hundred-thousand dollars less than the average original purchase price. The outstanding loans averaged $91,955, leading to an average owner equity of $83,194. Based on the sample, 85% of the federally permitted Gulf shrimp fleet was actively shrimping in 2006. Of these 386 active Gulf shrimp vessels, just under half (46%) were owner-operated. On average, these vessels burned 52,931 gallons of fuel, landed 101,268 pounds of shrimp, and received $2.47 per pound of shrimp. Non-shrimp landings added less than 1% to cash flow, indicating that the federal Gulf shrimp fishery is very specialized. The average total cash outflow was $243,415 of which $108,775 was due to fuel expenses alone. The expenses for hired crew and captains were on average $54,866 which indicates the importance of the industry as a source of wage income. The resulting average net cash flow is $16,225 but has a large standard deviation. For the population of active Gulf shrimp vessels we can state with 95% certainty that the average net cash flow was between $9,500 and $23,000 in 2006. The median net cash flow was $11,843. Based on the income statement for active Gulf shrimp vessels, the average fixed costs accounted for just under a quarter of operating expenses (23.1%), labor costs for just over a quarter (25.3%), and the non-labor variable costs for just over half (51.6%). The fuel costs alone accounted for 42.9% of total operating expenses in 2006. It should be noted that the labor cost category in the income statement includes both the actual cash payments to hired labor and an estimate of the opportunity cost of owner-operators’ time spent as captain. The average labor contribution (as captain) of an owner-operator is estimated at about $19,800. The average net revenue from operations is negative $7,429, and is statistically different and less than zero in spite of a large standard deviation. The economic return to Gulf shrimping is negative 4%. Including non-operating activities, foremost an average government payment of $13,662, leads to an average loss before taxes of $907 for the vessel owners. The confidence interval of this value straddles zero, so we cannot reject, with 95% certainty, that the population average is zero. The average inactive Gulf shrimp vessel is generally of a smaller scale than the average active vessel. Inactive vessels are physically smaller, are valued much lower, and are less dependent on loans. Fixed costs account for nearly three quarters of the total operating expenses of $11,926, and only 6% of these vessels have hull insurance. With an average net cash flow of negative $7,537, the inactive Gulf shrimp fleet has a major liquidity problem. On average, net revenue from operations is negative $11,396, which amounts to a negative 15% economic return, and owners lose $9,381 on their vessels before taxes. To sustain such losses and especially to survive the negative cash flow, many of the owners must be subsidizing their shrimp vessels with the help of other income or wealth sources or are drawing down their equity. Active Gulf shrimp vessels in all states but Texas exhibited negative returns. The Alabama and Mississippi fleets have the highest assets (vessel values), on average, yet they generate zero cash flow and negative $32,224 net revenue from operations. Due to their high (loan) leverage ratio the negative 11% economic return is amplified into a negative 21% return on equity. In contrast, for Texas vessels, which actually have the highest leverage ratio among the states, a 1% economic return is amplified into a 13% return on equity. From a financial perspective, the average Florida and Louisiana vessels conform roughly to the overall average of the active Gulf shrimp fleet. It should be noted that these results are averages and hence hide the variation that clearly exists within all fleets and all categories. Although the financial situation for the average vessel is bleak, some vessels are profitable. (PDF contains 101 pages)

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Summary: The offshore shelf and canyon habitats of the OCNMS (Fig. 1) are areas of high primary productivity and biodiversity that support extensive groundfish fisheries. Recent acoustic surveys conducted in these waters have indicated the presence of hard-bottom substrates believed to harbor unique deep-sea coral and sponge assemblages. Such fauna are often associated with shallow tropical waters, however an increasing number of studies around the world have recorded them in deeper, cold-water habitats in both northern and southern latitudes. These habitats are of tremendous value as sites of recruitment for commercially important fishes. Yet, ironically, studies have shown how the gear used in offshore demersal fishing, as well as other commercial operations on the seafloor, can cause severe physical disturbances to resident benthic fauna. Due to their exposed structure, slow growth and recruitment rates, and long life spans, deep-sea corals and sponges may be especially vulnerable to such disturbances, requiring very long periods to recover. Potential effects of fishing and other commercial operations in such critical habitats, and the need to define appropriate strategies for the protection of these resources, have been identified as a high-priority management issue for the sanctuary. To begin addressing this issue, an initial pilot survey was conducted June 1-12, 2004 at six sites in offshore waters of the OCNMS (Fig. 2, average depths of 147-265 m) to explore for the presence of deep-sea coral/sponge assemblages and to look for evidence of potential anthropogenic impacts in these critical habitats. The survey was conducted on the NOAA Ship McARTHUR-II using the Navy’s Phantom DHD2+2 remotely operated vehicle (ROV), which was equipped with a video camera, lasers, and a manipulator arm for the collection of voucher specimens. At each site, a 0.1-m2 grab sampler also was used to collect samples of sediments for the analysis of macroinfauna (> 1.0 mm), total organic carbon (TOC), grain size, and chemical contaminants. Vertical profiles of salinity, dissolved oxygen (DO), temperature, and pressure were recorded at each site with a small SeaCat conductivity-temperature-depth (CTD) profiler. Niskin bottles attached to the CTD also obtained near-bottom water samples in support of a companion study of microbial indicators of coral health and general ecological condition across these sites. All samples except the sediment-contaminant samples are being analyzed with present project funds. Original cruise plans included a total of 12 candidate stations to investigate (Fig. 3). However, inclement weather and equipment failures restricted the sampling to half of these sites. In spite of the limited sampling, the work completed was sufficient to address key project objectives and included several significant scientific observations. Foremost, the cruise was successful in demonstrating the presence of target deepwater coral species in these waters. Patches of the rare stony coral Lophelia pertusa, more characteristic of deepwater coral/sponge assemblages in the North Atlantic, were observed for the first time in OCNMS at a site in 271 meters of water. A large proportion of these corals consisted of dead and broken skeletal remains, and a broken gorgonian (soft coral) also was observed nearby. The source of these disturbances is not known. However, observations from several sites included evidence of bottom trawl marks in the sediment and derelict fishing gear (long lines). Preliminary results also support the view that these areas are important reservoirs of marine biodiversity and of value as habitat for demersal fishes. For example, onboard examination of 18 bottom-sediment grabs revealed benthic infaunal species representative of 14 different invertebrate phyla. Twenty-eight species of fishes from 11 families, including 11 (possibly 12) species of ommercially important rockfishes, also were identified from ROV video footage. These initial discoveries have sparked considerable interests in follow-up studies to learn more about the spatial extent of these assemblages and magnitude of potential impacts from commercial-fishing and other anthropogenic activities in the area. It is essential to expand our knowledge of these deep-sea communities and their vulnerability to potential environmental risks in order to determine the most appropriate management strategies. The survey was conducted under a partnership between NOAA’s National Centers for Coastal Ocean Science (NCCOS) and National Marine Sanctuary Program (NMSP) and included scientists from NCCOS, OCNMS, and several other west-coast State, academic, private, and tribal research institutions (see Section 4 for a complete listing of participating scientists). (PDF contains 20 pages)

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Forward: Looe Key National Marine Sanctuary (LKNMS) was designated in 1981 to protect and promote the study, teaching, and wise use of the resources of Looe Key Sanctuary (Plate A). In order to wisely manage this valuable resource, a quantitative resource inventory was funded by the Sanctuary Programs Division (SPD), Office of Ocean and Coastal Resource Management, National Oceanic and Atmospheric Administration (NOAA) in cooperation with the Southeast Fisheries Center, National Marine Fisheries Service, NOAA; the Cooperative Institute for Marine and Atmospheric Studies (CIMAS), University of Miami; the Fisher Island Laboratory, United States Geological Survey; and the St. Petersburg Laboratory, State of Florida Department of Natural Resources. This report is the result of this cooperative effort. The objective of this study was to quantitatively inventory selected resources of LKNMS in order to allow future monitoring of changes in the Sanctuary as a result of human or natural processes. This study, referred to as Phase I, gives a brief summary of past and present uses of the Sanctuary (Chapter 2); and describes general habitat types (Chapter 3), geology and sediment distribution (Chapter 4), coral abundance and distribution (Chapter 5), the growth history of the coral Montastraea annularis (Chapter 6), reef fish abundance and distribution (Chapter 7), and status of selected resources (Chapter 8). An interpretation of the results of the survey are provided for management consideration (Chapter 9). The results are expected to provide fundamental information for applied management, natural history interpretation, and scientific research. Numerous photographs and illustrations were used to supplement the report to make the material presented easier to comprehend (Plate B). We anticipate the information provided will be used by managers, naturalists, and the general public in addition to scientists. Unless otherwise indicated, all photographs were taken at Looe Key Reef by Dr. James A. Bohnsack. The top photograph in Plate 7.8 was taken by Michael C. Schmale. Illustrations were done by Jack Javech, NMFS. Field work was initiated in May 1983 and completed for the most part by October 1983 thanks to the cooperation of numerous people and organizations. In addition to the participating agencies and organizations we thank the Newfound Harbor Marine Institute and the Division of Parks and Recreation, State of Florida Department of Natural Resources for their logistical support. Special thanks goes to Billy Causey, the Sanctuary Manager, for his help, information, and comments. We thank in alphabetical order: Scott Bannerot, Margie Bastian, Bill Becker, Barbara Bohnsack, Grant Beardsley, John Halas, Raymond Hixon, Irene Hooper, Eric Lindblad, and Mike Schmale. We dedicate this effort to the memory of Ray Hixon who participated in the study and who loved Looe Key. (PDF contains 43 pages)

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This report documents abundance and cover for selected elements of the benthic coral reef assemblage at the site of the 1984 grounding of the M/V Wellwood on Molasses Reef, Florida Keys. The purpose of the effort was to establish a pre-construction baseline before the installation of reef modules at the site. The installation process is intended to stabilize fractured substrates that were recently exposed by storm impacts, and to provide three-dimensional relief in order to enhance reef community recovery. It is hoped that the restoration effort will result in a biological assemblage with the character of the transition community that would exist there had the incident not occurred. To date, the assemblage has developed the character of a comparatively featureless hard ground similar in composition to hard ground areas and transition zones surrounding the grounding site. These data will allow scientists and resource managers to better track the trajectory of recovery following the installation of modules. Direct counts of scleractinian and gorgonian corals, hydrocorals of the genus Millepora, and zoanthids of the genus Palythoa were made in three areas within and around the grounding site. The site is poorly developed with respect to scleractinian colony size and cover compared to surrounding areas. Key scleractinian species necessary for the development of topographic relief in the area denuded by the grounding are not well represented in the current community. Though gorgonian cover and richness is similar in all study areas, gorgonian community recovery in the damaged area is not complete. Unlike surrounding areas, one species, Pseudopterogorgia americana, accounts for over half of all corals at the grounding site, over 80% of all gorgonians, and nearly all the coral cover. Based on these findings and other observations made in the 18 years since the grounding, recommendations are made that should be considered in the course of human intervention targeted at stabilizing and enhancing the site. (PDF contains 24 pages.)

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Over the last several years, concern has increased about the amount of man-made materials lost or discarded at sea and the potential impacts to the environment. The scope of the problem depends on the amounts and types of debris. One problem in making a regional comparison of debris is the lack of a standard methodology. The objective of this manual is to discuss designs and methodologies for assessment studies of marine debris. This manual has been written for managers, researchers, and others who are just entering this area of study and who seek guidance in designing marine debris surveys. Active researchers will be able to use this manual along with applicable references herein as a source for design improvement. To this end, the authors have synthesized their work and reviewed survey techniques that have been used in the past for assessing marine debris, such as sighting surveys, beach surveys, and trawl surveys, and have considered new methods (e.g., aerial photography). All techniques have been put into a general survey planning framework to assist in developing different marine debris surveys. (PDF file contains 100 pages.)

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The objective of this study was to describe the physical and ichthyological changes occurring seasonally and annually in the south San Francisco Bay, based on the results of 2,561 otter trawl and water samples obtained between February 1973 and June 1982. Temperature varied predictably among seasons in a pattern that varied little between years. Salinity also underwent predictable seasonal changes but the pattern varied substantially between years. The most abundant species of fish were northern anchovy (Engraulis mordax), English sole (Parophrys vetulus), and shiner surfperch (Cymatogaster aggregata). The majority of the common fish species were most abundant during wet years and least abundant in dry years. Numeric diversity was highest during the spring and early summer, with no detectable interannual trends. Species composition changed extensively between seasons and between years, particularly years with extremely high or extremely low freshwater inflows. All the common species exhibited clustered spatial distributions. Such spatial clustering could affect the interpretation of data from estuarine sampling programs. Gobies (Family Gobiidae) were more abundant during flood tides than during ebb tides. English sole were significantly more abundant in shallower areas. Shiner surfperch showed significant differences in abundance between sample areas.(PDF file contains 28 pages.)

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Quarterly ichthyoplankton sampling was conducted at 16 estuarine and 24 inshore stations along the Florida Everglades from May 1971 to February 1972. The area is one of the most pristine along lhe Florida coast. The survey provided the first comprehensive information on seasonal occurrence, abundance (under 10 m' of surface area), and distribution of fish eggs and larvae in this area. A total of 209,462 fish eggs and 78,865 larvae was collected. Eggs were identified only as fish eggs, but among the larvae, 37 families, 47 genera, and 37 species were identified. Abundance of eggs and larvae, and diversity of larvae, were greatest in the inshore zone. The 10 most abundant fish families which together made up 90.7% of all larvae from the study area were, in descending order of abundance: Clupeidae, Engraulidae, Gobiidae, Sciaenidae, Carangidae, Pomadasyidae, Cynoglossidae, Gerreidae, Triglidae, and Soleidae. Clupeidae, Engraulidae, and Gobiidae made up 59.9% of all larvae. The inshore zone (to a depth of about 10 m) was a spawning ground and nursery for many fishes important to fisheries. The catch of small larvae (<>3.5 mm SL) indicated that most fishes identified from the 10 most abundant families spawned throughout the inshore zone at depths of <> 10 m, but Orthopristis chrysoptera, Gerreidae, and Prionotus spp. spawned at depths > 10 m, with offshore to inshore (eastward) larval transport. Salinity was one of several environmental factors that probably limited the numbers of eggs and larvae in the estuarine zone. Abundance of eggs and larvae at inshore stations was usually as great as, and sometimes greater than, the abundance of eggs and larvae at offshore stations (due west of the Everglades). (PDF file contains 81 pages.)

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The findings are presented of a survey conducted regarding the fishers of Lake Victoria, which examined the relationships affecting supply flows of raw material on to the market, and also the characteristics of fishing activities and their effects on fish quality and distribution. Fish marketing plays a vital role in the lives of much of the lake basin's population, both in terms of employment and nutrition. The results of the survey comprise, in part, a base-line data set which will facilitate further research, analysis and management decision-making in relation to stakeholders of the lake's resources. Data collection, methods and research difficulties encountered are described and details given of a profile of a boat owner/renter and aslo of a profile of a crew member. The survey shows that Lake Victoria's fishery is one of very limited diversity. The fishers recount that they consistently target one or more of the 3 most common species within the lake (Nile perch, tilapia and dagaa) and very rarely consider any other species type. The largest proportion of fishers on the lake are Nile perch fishers; there is considerable demand for this species, and hence fishers have little incentive to either target alternative fish species, not to try and establish firm marketing outlets through the creation of arrangements with their principal buyers. In Kenyan waters, however, the number of Nile perch fishers is equaled by the number of dagaa fishers; this fish now commands a considerable portion of the market for fish from Lake Victoria through its availability as well as its relatively low prices. The tilapia fishery is in decline, and all 3 riparian states would not appear to be attracting investment almost certainly as a result of declining catches. For many of those working in Lake Victoria's fishery, the problems faced appear most often to be associated with the vagaries of an unstable market which may rise or fall depending on the state of the international market or the state of access roads to fish landings. (PDF contains 42 pages)

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A survey was carried out in September 1996 alongside the annual frame survey of Kainji Lake, Nigeria. As in the previous surveys, there were 6 main fishing gear types in use on the lake, which included gill nets, drift nets, beach seines, cast nets, longlines (baited and foul hooking) acid fishing traps. A total of 813 canoes were sampled. The canoe lengths were similar to the previous gear surveys. Altogether 466 gill nets were measured. They had an average length of 149 m, and were mostly bottom set. Of the gill nets measured 68% had a mesh size below 3 inches the minimum mesh size allowable according to the Niger and Kebbi State Fisheries Edict, 1996. Of concern was the large increase in the number of 1 inch meshed nets recorded on the lake. Drift nets had a mean length of 74 m. A total of 88% of all drift nets measured had a mesh size below 2.5 inches, the minimum mesh size stipulated in the State Edict. A total number of 102 beach seines were sampled with a mean length of 110 m, the mesh size in use on the lake remained as 0.1 inches under the Edict beach seines are banned from fishing in Kainji Lake. The decline in the lengths of the beach seines (and therefore catch rates) recorded since l995 was encouraging in the light of the destructive nature of these nets. A total of 30 cast nets were sampled, they had a mean diameter of 9.8 and a mean mesh size of 1.9 inches. All the nets had a hanging ratio of 0.5. Of the cast nets measured 40% had a mesh size below the minimum size of 2 inches recommended by the State Fisheries Edicts. Of concern was the continued rise in the number of gill nets with mesh sizes less than 2 inches. There were 2 types of longlines in operation on the lake. The baited and the foul hooking longlines. They were mostly bottom set and the hook size nos. 12-14 (Kirby sea hook) were predominant. Two types of fishing traps were identified, one was covered with a mesh of thin cane, one with netting material. The fishing traps had a mean height of 0.8 m and a mean width at the vase of 0.53 m. The mean mesh size used was 0.86 inches. Citharinus was reported as the most targeted of all fish species on the lake. Synodontis membranaceous was also targeted by most gears especially the smaller meshed nets. Labeo and Tilapia were low on the list of targeted species but their incidence remains high in the catches. (PDF contains 27 pages)

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Since 1993, annual frame surveys have been conducted by the Nigerian-German Kainji Lake Fisheries Promotion Project to determine the distribution and number of fishing localities, fishing canoes and fishing gears around Kainji Lake, Nigeria. The total number of fishing localities has increased from 221 in 1993 to 286 in 1996. The fishing localities included 245 permanent fishing villages, 29 permanent fishing camps, 8 temporary fishing camps (with fishermen from Kainji Lake) and 4 temporary fishing camps (with fishermen from outside Kainji Lake area). There was an increase in the total number of fishing entrepreneurs, fishing assistants and fishing canoes over the years. A total number of 5,499 fishing entrepreneurs, 12,449 fishing assistants and 9,278 fishing canoes were recorded during the 1996 frame survey. From 1995 there was a decrease in the number of shoreline fisherfolk and a decrease in the number of transport canoes, the number of engines remained the same. During the 1996 survey, a total number of 18,655 gill nets, 1,560 drift nets, 753 beach seines, 5,548 cast nets, 7,400 longlines and 36,979 traps were recorded. The concentration of the gears (number per km shoreline) was highest in substrata 06 and 08. The total number of gill nets increased from 17,680 in 1995 to 18,655 in 1996. For the remaining 5 gear types a decrease in number was observed. Despite increasing numbers of gears on the lake, of concern is the decline recorded in all the fishing methods of the number of gears owned by individual entrepreneurs. This was most notable in the gill net and longline fisheries. These two fisheries have the lowest daily catch values and coupled with the problem of gear theft on the lake, ownership in future, may be expected to fall further. The number of larger fishing units also declined as did the number of gears new entrants enter the fishery with. The decline is particularly worrying for the beach seine fishery where diversification into other fishing methods would be beneficial in light of the present ban on seines. The group of not active fishing entrepreneurs (those who do not themselves participate in fishing activities) had the highest ownership of gears whilst the new entrants into the fishery had the lowest. There was evidence that these new entrants into the fishery were using cast nets which is worrying given the trend of using smaller mesh size of this gearSince 1993, annual frame surveys have been conducted by the Nigerian-German Kainji Lake Fisheries Promotion Project to determine the distribution and number of fishing localities, fishing canoes and fishing gears around Kainji Lake, Nigeria. The total number of fishing localities has increased from 221 in 1993 to 286 in 1996. The fishing localities included 245 permanent fishing villages, 29 permanent fishing camps, 8 temporary fishing camps (with fishermen from Kainji Lake) and 4 temporary fishing camps (with fishermen from outside Kainji Lake area). There was an increase in the total number of fishing entrepreneurs, fishing assistants and fishing canoes over the years. A total number of 5,499 fishing entrepreneurs, 12,449 fishing assistants and 9,278 fishing canoes were recorded during the 1996 frame survey. From 1995 there was a decrease in the number of shoreline fisherfolk and a decrease in the number of transport canoes, the number of engines remained the same. During the 1996 survey, a total number of 18,655 gill nets, 1,560 drift nets, 753 beach seines, 5,548 cast nets, 7,400 longlines and 36,979 traps were recorded. The concentration of the gears (number per km shoreline) was highest in substrata 06 and 08. The total number of gill nets increased from 17,680 in 1995 to 18,655 in 1996. For the remaining 5 gear types a decrease in number was observed. Despite increasing numbers of gears on the lake, of concern is the decline recorded in all the fishing methods of the number of gears owned by individual entrepreneurs. This was most notable in the gill net and longline fisheries. These two fisheries have the lowest daily catch values and coupled with the problem of gear theft on the lake, ownership in future, may be expected to fall further. The number of larger fishing units also declined as did the number of gears new entrants enter the fishery with. The decline is particularly worrying for the beach seine fishery where diversification into other fishing methods would be beneficial in light of the present ban on seines. The group of not active fishing entrepreneurs (those who do not themselves participate in fishing activities) had the highest ownership of gears whilst the new entrants into the fishery had the lowest. There was evidence that these new entrants into the fishery were using cast nets which is worrying given the trend of using smaller mesh size of this gear. (PDF contains 44 pages)

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This study includes an analysis of the trawl survey that was carried out by the Kainji Lake Fisheries Promotion Project in May, 1997. The objective of the survey was to assess the biomass and the potential yield of clupeids and the carrying capacity of the beach seine fishery in the entire Kainji Lake (Nigeria). The biomass of the beach seine by-catch was also estimated. The density (kg /km super(3)) of the clupeids was higher in the Bussa and Foge than in the other stations. The lowest density of clupeids was in the Anfani station followed by Jetty, both in the southern basin. These stations were the deepest parts of all the areas trawled, measuring between 37-120 m of depth. There was an inverse correlation between depth trawled and the catch rates of clupeids, though the correlation was poor. The average annual biomass of the clupeids was estimated at 36,769.85 Mt in the entire Lake with an MSY of 11,705.95 Mt. The smaller species, Sierrathrissa leonensis, made up about 97% of the total clupeid population in the lake and occurred at a shallower depth than the larger species Pellonula afzeliusi. From the clupeid production statistics in 1996, it is estimated that the MSY is already overshot by 34%. Therefore, about 698 beach seines instead of the present 810 would be sufficient for sustainable exploitation of the clupeid stocks. Because of the substantial by-catch in the beach seines, this fishing method was banned from Kainji Lake in 1997. An offshore open water seine net is recommended to replace the beach seines on the lake. The number of these nets should not exceed 500. The current ban on beach seine is supported by this study. Nevertheless, and since the ban may not be 100% effective, effort should concentrate on maintaining that the number of beach seines must be kept at most at the present level. Recommendation is made against the introduction of the pair trawling not only from an economic point of view but also for resource conservation, legal and social reasons. The development of this fishery could pose a serious danger to continuity of stocks. It is proposed that priority be given to the development of an open water seine which is at the same level of exploitation as the beach seine and requires similar cost to acquire. (PDF contains 39 pages)

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Survey of Fungal infestation of some species of fish in Tagwai Dam Minna was carried out from March to June 2002. Fungi were isolated from the scale/skin, gills and fins. Twenty-one fungi species were identified from 18 species of fish microbial growth was measured by direct cell count using Stuart colony counter. Most of the fungi encountered were of the mould group and infestation occurred among all the species sampled. The infestation was predominantly by Aspergillus species and the scale/skin was most widely affected. The study showed the identified fungi in order of frequency to be as follows. Aspergillius niger. Rrhizopus spp. Mmucor spp Aspergilus flavum. Aspergillus parasitous. Aspergillus fumigatus, Microsporum canis. Penicillum virridicalumand Fusarium spp respectively. Aspergillus niger occurred on all the species of fish sampled. Barrilius spa and Chrysichrhy auratus longifilis had significantly higher (P<0.05) mean fungal load on their fins and gills. There was no significant difference (P>0.05) in the mean fungal load in different parts of the body of other fish species sampled

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The first comprehensive CAS was carried out during the month of July 2005 This is the second report of CAS for the month of August 2005 following the July report. The design and methodology followed was the same as in July. This report highlights the results obtained in August catch assessment survey. The report gives estimates of mean catch rates in Kgs./boat/day, total catches in M.tons and values of the catch by species. The total catch for August was 31,633.0 M. tons. This is lower when compared with the July catch which was 39,745.1 M. tons. In August the catch composed of Dagaa (45%), Nile perch (33%), Haplochromines (16%), Tilapiines (5%) and all other species combined (1%). (PDF contains 14 pages)

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1) The 4-beaches survey was the first of its kind on Lake Victoria. Drawing on Participatory Rural Appraisal (PRA) techniques, four landing sites around the lake were selected for long-term monitoring from March 2000 through to October 2001. 2)Held in all the 3 riparian countries of Lake Victoria the stakeholders' workshops aimed to assess the necessity of fisheries management for Lake Victoria and to identify who the stakeholders in fisheries management would be.

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As it is clearly indicated in the title of this book section, it overviews the methodologies used in the 4-beaches Survey and in the various Stakeholders' Workshops held in all the three riparian countries of the Lake Victoria.