Cephalopod fishery at Kakinada along the east coast of India: Resource characteristics and stock assessment of Loligo duvauceli ·

At Kakinada along the east coast of India, cephalopods were exploited by trawls. Fishery occurred round the year with peak during August-October. Peak abundance and fishery of cuttlefishes coincides with this period, whereas for squids it is during March-May. Cephalopod production continued to increase initially with fishing effort, until 1995, but declined thereafter despite increased fishing effort and expansion of fishing to deeper waters. Fishery, growth, mortality, recruitment pattern and exploitation rates of Loligo duvauceli were studied. Nearly 97% of their catch was by zero year groups. They attain sexual maturity and spawn during the first year itself. Spawning occurred round the year with peak during December-February. Exploitation rate of the species is large, 0.741 compared to Emax (0.44). This indicated that their stock is under heavy fishing pressure and subjected to over-exploitation. Stock also exhibited declining trend over the years during 1995-'99. These necessitate immediate attention to avoid coHapse of the stock and fishery.

Catch efficiency and selective action of coloured gill nets

Information on the catch efficiency and selective action of coloured gill nets in relation to the reservoir fishes of India are lacking. Authors, in the present studies have attempted to evaluate the comparative catch efficiency of gill nets of four shades viz. yellow, orange, green and blue over the colourless ones, by conducting fishing experiments, in the Govindsagar reservoir. Attempts have also been made to study the preference shown to colours by the four major species of fishes of the reservoir.

Studies on the growth and production of six major and exotic carps in Nasti baor, Jhenaidah, Bangladesh

An investigation on growth, production and fishery of three Indian major carps: rohu, Labeo rohita, catla, Catla catla and mrigal, Cirrhinus mrigala and three exotic carps: silver carp, Hypophthalmichthys molitrix, grass carp, Ctenopharyngodon idella, and common carp, Cyprinus carpio was carried out in Nasti baor during February to April months. In catch per unit effort (CPUE) study the highest catch/day/person (3.13 kg) and catch/day/gear (40.65 kg) was recorded in the month of March for kochal fishing. In komar fishing catch/day/person (15.08 kg) and catch/day/gear (1206 kg) was also found higher in March. Komar fishing was done only in March and April and its CPUE was greater in both the months than that of kochal. The average recovery rate (combination of all six species) was 37.80 considering the stocking from July month of the previous year. The recovery rate of common carp (54.1) was the highest and lowest (13.90) in case of silver carp. When the recovery was calculated on the basis of one year data and stocking, it was 55.6%. Analysis of production model revealed that the present production (54,806 kg/year) is less than both theoretical production (model I- 85,285 kg/year and model II -75,952 kg/year) estimated. Therefore, it may be concluded that the fish production from Nasti baor could still be increased from the present level of production.

An assessment of handling and processing methods used for the shrimp fishery by-catch in Kalpitiya, Sri Lanka

The by-catch from the shrimp trawl fishery in Kalpitiya is mainly used for the production of dried fish, which provides an additional source of income for fishermen in the area. It has been observed that current handling practices along the value addition chain are responsible for the poor quality and low price of the end product. This study was aimed at identifying the shortcomings in such handling practices by fishermen and dried fish producers and assessing the quality of shrimp fishery by-catch along the processing chain in order to recommend more efficient utilization methods that will improve the quality of the end product. Fresh fish, dried fish and harbour water samples were tested for total coli forms, faecal coliforms, E. coli and Salmonella in order to assess their microbial quality: In addition, standard plate counts (SPC) of fish samples were also carried out. A survey was carried out from July-October 2006 at Kalpitiya, using a pre-tested questionnaire to collect information from individuals who have been engaged in dried fish processing. Average values obtained for freshly landed and dried fish respectively, were, SPC 9.88x10 super(5) CFU/g and 30.43x10 super(5) CFU/g, total coliforms 23.05 and 24.23 MPN/g and fecal coliforms 8.28 and 9.00 MPN/g. These values exceed the recommendations in the SL standards. A quarter of the landed fresh fish and 38% of dried fish from the producers were positive for E. coli and thus failed to show required end product quality. SPC of harbour water was 14.35x10 super(6) CFU/ml and all samples were found to be contaminated with E. coli. None of the fishermen and dried fish producers were satisfied with the quality of the end product. The reasons for poor quality as indicated by them were: limited availability of ice (75%), lack of infrastructure facilities (65%), uncertainty of markets (52%), lack of emphasis on quality (47%) and poor access to available technologies (41%). Respondents to the questionnaire also identified: unavailability of potable water, insulated boxes, good landing jetty, racks for drying fish, poor cold storage facilities and limitations in dried fish storage facilities, as further factors leading to the loss of quality in their products. Results demonstrate that improvements to the infrastructure facilities and conducting of proper awareness programmes on handling practices could lead for improvements in the quality of value added products prepared from the shrimp fishery by-catch at Kalpitiya.

The decline of Alestes baremose Boulenger, 1901 and Hydrocynus forskahlii (Cuvier, 1819) stocks in Lake Albert: implications for sustainable management of their fisheries

The fish stocks of Lake Albert face immense exploitation pressure which has led to “fishingdown” of their fisheries, with some larger species having been driven to near-extinction, while others such as Citharinus citharus have almost disappeared. Both A. baremose (Angara) and H. forskahlii (Ngassia) historically formed the most important commercial species in Lake Albert until the early 2000s but recent Catch Assessment Surveys (2007-2013) revealed a sweeping decline in their contribution to the commercial catch from 72.7% in 1971 to less than 6% in 2013. The catch per unit effort also registered a two-fold decline from 45.6 and 36.1 kg/boat/day to 22.6 and 18.1 kg/boat/day for A. baremose and H. forskahlii respective between 1971 and 2007. Over 50% of illegal gillnets, below the legal minimum limit of four inches (101.6 mm) used on Lake Albert target the two species. Gillnet experiments found the three inch (76.2 mm) gill net mesh size suitable for sustained harvest of the two species. The study concludes that optimal utilization of the two species and probably other non target fish species is achievable through species specific management strategies, coupling species specific licensing, and controlling harvest of juvenile individuals, overall fishing effort and fish catch on Lake Albert and protecting the vulnerable fish habitats.

Fishing gear selectivity of Lates niloticus L. (Nile perch), Oreochromis niloticus L. (Nile tilapia) and Rastrineobola argentea Pellegrin (Mukene) in lakes Victoria, Kyoga and Nabugabo

Catch effort data on which fisheries management regulations are sometimes based are not available for most lakes in Uganda. However, failure to regulate fishing gears and methods has been a major cause of collapse of fisheries in the country. Fisheries have been damaged by destructive and non-selective fishing gears and methods such as trawling and beach seining, by use of gill nets of mesh size which crop immature fish and by introduction of mechanised fishing. Selectivity of the gears used to crop Lates niloticus 1. (Nile perch), Oreochromis niloticus 1. (Nile tilapia) and Rastrineobola argentea (Mukene) which are currently the most important commercial species in Uganda were examined in order to recommend the most suitable types, sizes and methods that should be used in exploiting these fisheries . Gill nets of less than 127 mm mainly cropped immature Nile ti1apia and Nile perch. To protect these fisheries, the minimum mesh size of gill nets should be set at 127 mm. Seine nets of 5 mm do catch high proportions of immature Mukene while those of 10 mm catch mainly mature Mukene. When operated inshore, both sizes catch immature Nile perch and Nile ti1apia as by-catch. To protect the Mukene fishery and avoid catching immature byecatch, a minimum mesh size of the Mukene net should have been 10 mm operated as Lampara type net offshore but since most fishennen have been using the 5 mm seine for over five years the minimum size should not be allowed to drop below 5 mm pending further thorough investigations. Beach seining, trawling and are destructive to fisheries and should be prohibited until data that may justify their use is available.

Aquatic ecology monitoring, water quality, fish, fish catch, sanitation and disease vectors: monitoring no. 11, 4th – 9th September 2012

This monitoring survey No. 11 undertaken between 4th and 9th September 2012 is the second one to be conducted after completion of construction of Bujagali Hydropower Dam. Two pre-construction baseline surveys in April 2000 and April 2006 were conducted and during construction phase, eight monitoring surveys (September 2007, April 2008, April 2009, October 2009, April 2010, September 2010, April 2011, September 2011) were conducted.

Report on Lake Wamala fisheries catch assessment survey 2012

Lake Wamala is one of the small lakes in Uganda, and lies between latitudes 0o 15; and 0o 25' N 31o 45' to longitude 32o 00' E, longitude and at an altitude of 1000m above sea level. Following ths 1961 heavy rains the lake expanded from about 100 to 118 sq. km and the swamps covered almost 60 sq km (Okaranon 1993). This lake was first stocked with Oreohromis niloticus eduardianus populary known as Oreohromis niloticus then Oreochromis leucostictus and then Tilapia zillii then after that it was officially opened for commercial fishing in 1960. Despite of the commercial fishery there used to be subsistance fishing that was mainly by the use of wires and hooks and targeted the Clarias and Protopterus species. The lake fishery used to be highly profitable after the opening in 1960; though in 1970s the fishers started complaining of the declining state of the fishery. At that time the O. niloticus had gone down to less than 1 kg per net per night by 1975 (Okaranon 1993). Due to it led to scientists undertake fisheries surveys in 1975/78 and later 1988/92 then later on there subsquent survey in 2003. Since that time there has been no work done until March 2012 that both catch assessment and frame surveys undertaken to ensure that management issues are addressed concerning this riparian water body. The main objectives of the survey were:- To assess fish production levels in the commercial fisheries of Lake Wamala (Catch Assessment). To assess the fishing effort and facilities available at the fish landings that supports the fisher folks.

Monthly patterns in physico-chemical conditions and fish catch in the immediate vicinity of the Bujagali hydropower construction site 29th September - 28th October 2007

The specific objectives were to: WATER QUALITY 1. To measure the water physical variables as indicators of environmental conditions in the upstream and downstream transects of Kalange (1) and Buyala (2), respectively, 2. To determine the concentrations of total suspended solids as a major constituent likely to be released into the waters at any time during the construction activities, by comparing the concentrations at the two transects. FISH CATCH 1. To follow up trends in fish catch as construction activity progresses, and to precision of the estimate; 2. To estimate the prevailing fish catch rates, total fish catches and the total value of the fish catch to the local fishers at the two transects.

An analysis of the 1970 commercial fish catch in three areas of the Kafue Floodplain

The commercial landings of fish in three areas of the Kafue Floodplain were examined in regard to thhing technique used, catch per unit effort, and species composition and length size. Gillnets were used throughout the year although predominantly in the wet season, and drawnets (similar to beach seines) were used at periods of low water level. Fishermen used a varying number of gillnets in each area, and the catehes also varied according to month. Principal species caught on the floodplain were clarias gariepinus and Tilapia andersoni. There are indications that, whereas the catch per gillnet in the year's 1965-1970 may be lower than in the 1950s. The drawnet calch per unit of effort of these later years is higher than in the 1950s.

On the fishes and fisheries of Lake Baringo

Six fish species are known to occur in Lake Baringo. Tilapia nilotica Linnaeus 1757, Barbus gregorii Boulenger 1902, Clarias mossambicus Peters 1852 and Labeo cylindricus Peters 1852 were recorded in 1930-31. In 1969, two more fish species were identified: Aplocheilichthys sp. and Barbus lineomaculatus Boulenger 1903. T. nilotica is the only fish species commercially exploited. But the catches, catch per unit effort and the mean size of fish caught in commercial gillnets have declined since 1968. B. gregorii is important in the subsistence rod-and-line fishery. L. cylindricus, C. mossambicus, B. lineomaculatus and Aplochelichthys sp. are not commercially exploited.

Approaches to the evaluation and management of the fish stock in Kainji Lake, Nigeria

Estimates of potential yield for Kainji Lake, and the methods of analysis by earlier workers are discussed. Also summarized is the state of the fishery after impoundment, between 1969 and 1971, based on experimental gillnet catches. Recent sampling of the young of the year along the littoral margin indicates that most of the commercially important species have spawned successful1y in the lake. An intense fishing mortality of juvenile fish, owing to the use of small mesh nets by local fishermen, presents a possible threat to the future establishment of the fish in the lake. The results of gill-net selection studies based on HOLT'S (1957) method are given. The data have been extracted from experimental gill-net catches with graded fleets of nets between 1969 and 1971. Recommendations based on the above studies have been made to ensure a successful establishment of the fish species in the lake and an increase in catch-per~unit effort in subsequent years.

The increased fishing pressure and the future of the fish stocks of Lake Victoria, Uganda

The Uganda sector of Lake Victoria occupies 29,580 km2 (43%). The lake used to boast of a multi-species fishery but presently relies on three major species Lates niloticus, Oreochromis niloticus and Rastrineobola argentea. During the past decade the total fish production on the Ugandan sector increased drastically from 17,000 tonnes in 1981 to about 13,000 tonnes 1991, indicating a healthy state of the fishery. This was contributed by a combination of factors including the explosive establishment of the introduced L. niloticus which contributed 60.8% in 1991 and the increase in the number of fishing canoes from 3470 in 1988 to 8000 in 1990. Isolated fishery resources studies carried out in different areas of the lake since 1971 seem, however, to indicate contrary trends in the available stocks and, therefore, the status of the fishery. In the experimental fishery, continued decline in catch rates have been recorded. Similarly, in the commercial fishery catch per unit of effort has been considerably poor (33 kg per canoe during January - March 1992) and the average size of individual fish laRded continued to decline, obviously pointing at possible over-fishing. This, therefore, calls for further urgent research on the available stocks for proper management strategies to be formulated.

A decline in fish catches and the size of Oreochromis niloticus in Lake Wamala (Uganda) following human exploitation

The fishery of Lake Wamala has declined since the lake was stocked in 1956 and opened to fishing during the 1960s. Surveys were conducted on the lake during 1975/78 and 1988/92 to investigate the causes of declining fish catches. The lake produced an average of 4000 - 6000 tonnes of fish annually from 1960s through 1970s. Total fish catches decreased from a maximum of 7100 tonnes in 1967 to less than 500 tonnes by 1990s. Catch rates decreased from about 8 kg in the 1960s to less than 1 kg per net per night by 1975. During the 1970s the catch was dominated by Oreochromis niloticus (67%) followed by Clarias gariepinus (17%), and Protopterus aethiopicus (15.1 %). By 1990s the proportion of O. niloticus had decreased to 45.1% while that of P. aethiopicus had increased to 37.6%. These changes seem to have been caused by overfishing resulting from increased fishing effort from the recommended 250 to about 1000 boats and the additional increase in effort through driving fish into the nets by beating water. The maximum size of O. niloticus in the fishery decreased from 32 cm total length in 1975/78 to 22 cm in 1988/92 while the size at first maturity decreased from about 21 cm to 14 cm during the period. This has been concurrent with a shift in the mesh size of gillnet used from 127 mm (5") in 1960s to 64 mm by 1990s. Environmental changes, especially in lake level in 1980, may also have affected the fishery.

How smokers may react to cigarette taxes and price increases in Brazil: data from a national survey

Background: Despite being the third largest tobacco producer in the world, Brazil has developed a comprehensive tobacco control policy that includes a broad restriction on both advertising and smoking in indoor public places, compulsory pictorial warning labels, and a menthol cigarette ban. However, tax and pricing policies have been developed slowly and only very recently were stronger measures implemented. This study investigated the expected responses of smokers to hypothetical price increases in Brazil.Methods: We analyzed smokers' responses to hypothetical future price increases according to sociodemographic characteristics and smoking conditions in a multistage sample of Brazilian current cigarette smokers aged >= 14 years (n = 500). Logistic regression analysis was used to examine the relationship between possible responses and different predictors.Results: in most subgroups investigated, smokers most frequently said they would react to a hypothetical price increase by taking up alternatives that might have a positive impact on health, i.e., they would try to stop smoking (52.3%) or smoke fewer cigarettes (46.8%). However, a considerable percentage responded that they would use alternatives that would reduce the effect of price increases, such as the same brand with lower cost (48.1%). After controlling for sex age group (14-19, 20-39, 40-59, and >= 60 years), schooling level (>= 9 versus <= 9 years), number of cigarettes per day (>20 versus <= 20), and stage of change for smoking cessation (precontemplation, contemplation, and preparation), lower levels of dependence were positively associated with the response I would try to stop smoking (odds ratio [OR], 2.19). Young age was associated with I would decrease the number of cigarettes (OR, 3.44). A low schooling level was strongly associated with all responses.Conclusions: Taxes and prices increases have great potential to stimulate cessation or reduction of cigarette consumption further among two important vulnerable populations of smokers in Brazil: young smokers and those of low educational level. the results from the present study also suggest that seeking illegal products may reduce the impact of increased taxes, but does not eliminate it.