Non-Consumptive Activities on a Public Hunting and Fishing Area

The activities of all 1513 individuals who visited a public hunting and fishing area near Spearfish, South Dakota, USA, were recorded from May 16 to August 16, 2006. Over the entire period, slightly less than 60% of the visitors were engaged in fishing, and they accounted for nearly 80% of the total visitation time. Over 40% of the visitors were primarily there for non-consumptive (not hunting or fishing) reasons, including touring (sight-seeing), dog training and exercising, and swimming. Less than 1% of the visitors were there for photography. The percentage of visitors fishing decreased from a high of over 65% in the first 31-day period to less than 50% in the third 31-day period, with nearly all of the non-consumptive activities showing a reverse trend. The percentage of visitors swimming or conducting dog activities doubled from the first to third periods. The percentage of time that visitors spent fishing decreased over time, while the time spent on non-consumptive activities increased. However, the increase in non-consumptive activity time was not necessarily in proportion to the increase in the number of visitors involved with non-consumptive activities. By the final period, more visitors were at the area for touring, dogs, and swimming, than for fishing, but fishing still accounted for most of the visitation time. These results indicate an abundance of non-consumptive activities on a public area purchased and maintained with revenue from consumptive hunting and fishing activities, creating the opportunity for user conflicts and potentially threatening the user-pay model of natural resource conservation.

A Comparative Study of Fish Assemblages Near Aquaculture, Artificial and Natural Habitats

Habitat plays a critical role in regulating fish community structure. Using the data collected from a monthly trammel net survey in Ma'an archipelago off the east coast of China, we evaluated impacts of five different habitats(artificial reefs, mussel farms, cage aquaculture, rocky reefs and soft bottom) on fish assemblages. This study suggests that artificial reefs(AR) have significantly higher species richness, abundance and diversity than mussel farms(MF) or soft bottom(SB) habitats during most seasons, and that fish taxa in the AR habitats are similar to those in the rocky reef(RR) habitats. Two different fish assemblage patterns were revealed in the study area using non-metric multidimensional scaling ordination: an assemblage dominated by reef fishes(especially by Scorpaenidae species) in AR, RR and cage aquaculture(CA) habitats and an assemblage dominated by Sciaenidae species in MF and SB habitats. We suggest that reef fishes play a key role in differentiating fish community structures in the study area. Although few differences in fish abundance and diversity were found between the CA and SB habitats, a more diverse age structure was observed in the CA habitats. A much more complex fish assemblage and enhanced population of local species were established as a result of the presence of both floating and fixed artificial structures, probably through improved survival rates.

Tidal Flushing Time of Marine Fish Culture Zones in Hong Kong

Accurate determination of flushing time is crucial for maintaining sustainable production in fish culture zones （FCZs）, as it represents the physical self-purification capability via tidal exchange with clean water in the outer sea. However, owing to the temporal and spatial complexity of the coastal flushing process, existing methods for determining flushing time may not be generally applicable. In this paper, a systematic method for determining the flushing time in FCZs is presented, in which bathymetry, runoff, tidal range and stratification are properly accounted for. We determine the flushing time via numerical tracer experiments, using robust 3D hydrodynamic and mass transport models. For FCZs located in sheltered and land-locked tidal inlets, the system boundary can be naturally defined at the connection with the open sea. For FCZs located in open＇waters, hydrodynamic tracking is first used to assess the extent of tidal excursion and thus delimit the initial boundary between clean water and polluted water. This general method is applied to all designated marine FCZs in Hong Kong for both the dry and wet seasons, including 20 sheltered FCZs （in semi-enclosed waters of Tolo Harbour, Mirs Bay, and Port Shelter） and 6 FCZs in open waters. Our results show that flushing time is the longest in inner Port Shelter （about 40 days in dry season）, and the shortest for the FCZs in open waters （less than one week in dry season）. In addition, the flushing time in dry season is commonly longer than that in wet season： 20%~40% for most well-sheltered FCZs; 2.6-4 times for the others. Our results indicate a positive correlation between the flushing time and distance to open boundary, supporting the view that the flushing time of a FCZ is closely related to its location. This study provides a solid basis for mariculture management such as the determination of carrying capacity of FCZs.

Impact of Rice-Catfish/Shrimp Co-culture on Nutrients Fluxes Across Sediment-Water Interface in Intensive Aquaculture Ponds

Exchange of nitrogen and phosphorus across sediment-water interface plays an important role in the management of nutrient recycling in the aquaculture pond. In this study, a plot experiment was conducted to study the effect of rice-catfish/shrimp co-culture on the micro-profile of oxygen (O2), pH and nutrient exchange across sediment-water interface in the intensive culture ponds. The results showed that rice-catfish co-culture increased the concentration and penetrating depth of O2, but decreased the pH value across the sediment-water interface, compared with catfish monoculture. Additional rice cultivation significantly reduced the flux rates of ammonium (NH4+) and nitrate (NO3-) across sediment-water interface in the catfish and shrimp ponds. The flux rates of NO2 - and soluble phosphorus (PO43-) showed no significant difference between rice-catfish/shrimp co-culture ponds and catfish/shrimp monoculture ponds. Rice only affected the dissolved inorganic nitrogen and phosphorus fractions in the sediment. The concentrations of NH4 + were significantly lower in the sediment of co-culture ponds than in the monoculture ponds. Additional rice cultivation also significantly reduced the content and percentage of dissolved inorganic phosphorus in the sediment of catfish ponds.

Effects of Rice-Fish Co-culture on Oxygen Consumption in Intensive Aquaculture Pond

Rice-fish co-culture has gained increasing attention to remediate the negative environmental impacts induced by intensive aquaculture. However, the effect of rice-fish co-culture on oxygen depletion has rarely been investigated. We constructed a rice-fish co-culture system in yellow catfish(Pelteobagrus fulvidraco) and freshwater shrimp(Macrobrachium nipponense) ponds using a new high-stalk rice variety, and conducted a field experiment to investigate the effect of rice-fish co-culture on water parameters and oxygen consumption. The results showed that rice-fish co-culture reduced the nutrients(total nitrogen, ammonia-N, total phosphorous and potassium) and the dissolved oxygen content in fish and shrimp ponds. However, they showed similar seasonal change of dissolved oxygen in the water of fish and shrimp ponds. Rice-fish co-culture reduced the total amount of oxygen consumption and optimized the oxygen consumption structure in pond. The respiration rates in water and sediment were significantly reduced by 66.1% and 31.7% in the catfish pond, and 64.4% and 38.7% in the shrimp pond, respectively, by additional rice cultivation. Rice-fish co-culture decreased the proportions of respiration in sediment and water, and increased the proportion of fish respiration. These results suggest that rice-fish co-culture is an efficient way to reduce hypoxia in intensive culture pond.

ELECTRON MICROSCOPE EVIDENCE OF VIRUS INFECTION IN CULTURED MARINE FISH

Electron microscope investigation on the red sea bream ( Pagrosomus major ), bastard halibut ( Paralichthys olivaceus ) and stone flounder ( Kareius bicoloratus ) in North China revealed virus infection in the bodies of the dead and diseased fish. These viruses included the lymphocystis disease virus (LDV), parvovirus, globular virus, and a kind of baculavirus which was not discovered and reported before and is now tentatively named baculavirus of stone flounder ( Kareius bicoloratus ).

The Effects of Pen Fish Culture on the Ecological Environments of Taihu Lake

Effects of pen fish culture in Taihu lake were studied and summarized. During 1984 to 2001, pen fish culture of Taihu lake developed from extensive models to intensive and high-returned ones, the cultured species were shifted from fishes to crabs. Pen fish culture has caused eutrophication and detrimental effect to the ecological environment and fishery. The measures of sustainable development for pen fish culture and ecological environment protection were suggested.

Argungu International Fishing and Cultural Festival Inscribed on the Representative List of the Intangible Cultural Heritage of Humanity in 2016

Every year in northwest Nigeria, communities gather to participate in the Argungu International Fishing and Cultural Festival near the Matan Fada River. The four day festival, which runs between late February and March, features kabanci, a series of water competitions including hand fishing, canoe racing, wild duck catchi ng as well as other traditional practices, such as the local style of wrestling and boxing. Men and boys participate in the con tests, while women provide the encouragement by performing songs and dances.

The Program of Fish Culture in rice fields has been developed in Zhejiang Province

1996 is the first year for realizing the object of fish culture in 66,600 ha of rice field in Zhejiang Province. The provincial government has appropriated $ 24,000 per ha for starting capital. Starting from this year, counties with the tradition of fish culture in rice fields as Youngjia and Qingtian have put stress on popularizing the new technique of fish culture in ditches and puddles to raise the yield for per unit area. In areas of Central Zhejiang and North Zhejiang with hilly land and plain area with double—season rice, people have changed traditional fish varieties into special and excellent fish varieties.

Evaluation of Nutrient Components and Nutritive Quality of Larimichthys crocea(Big Yellow Croaker)in Different Aquaculture Models

To ascertain the nutrient components and nutritive quality of the flesh of big yellow croaker in three culture conditions （ traditional cage, offshore cage and cage-free）, basic nutritional components,amino acid,fatty acid and mineral elements were determined. The results indicated that crude protein in flesh of the big yellow croaker in cage-free culture was higher than that in offshore cage and much higher than that in traditional cage （ P 〈0.05）. Crude fat of the croaker cul- tured in the traditional cage was twice as high as that in cage-free culture, while that in the offshore cage was in the middle. Proline content in the cage-free culture was much higher than that in the offshore cage, and also than that in the traditional cage （P 〈 0.05 ）. There was no significant difference in the content of alanine, methionine and tryptophan （ P 〈 0.05）. Contents of other amino acids had no significant difference between the cage-free culture and offshore cage, but were much lower in the traditional cage （P 〈 0.05 ）. Top six fatty acids were 9-Hexadecenoic acid, palmitic acid,9-Octadecenoic acid, Octadecauoic acid, DHA and EPA. The palmitic acid content was the highest in cage-free culture and in traditional cage, 9-Octadeeenoic acid content was the highest in offshore cage. Content of unsaturat- ed fatty acids in cage-free culture, offshore cage and traditional cage was 63.60,66.32,57.67, respectively, and polyunsaturated fatty acid was 29.10, 28.57, and 24.40. Content of DHA in cage-free culture was significantly higher than that in the offshore and traditional cage. Content of zinc had no significant difference in three culture models. Content of phosphorus had no significant difference between that in cage-free culture and offshore cage, was lower in the traditional cage. The cage-free cultured croakers had the highest content of calcium and phosphorus. Content of selenium was about the same between the offshore cage and the traditional cage stocking, higher in the cage-free culture. This research has considerable application value for identifying quality and sources of the big yellow croakers.

Hydrogen Sulfide in Proliferating and Differentiated Cells in Primary Cultures of Juvenile Brain of Masu Salmon <i>Oncorhynchus masou</i>

Analysis of proliferative activity and the ability to neuron differentiation was performed in cultured cells of the brain and spinal cord of juvenile masu salmon Oncorhynchus masou. Proliferating cell nuclear antigen (PCNA) was used as a proliferative marker, while the markers of neuronal differentiation—a neuron protein HuCD, and a neuron-specific transcriptional factor with two DNA- binding sites Pax6—detected neurons. The results showed that cell proliferation occurred mainly in the suspension cell fraction. In monolayer, a few cells were only found to express PCNA. The results of morphological and immunohistochemical analysis allow us to conclude that proliferative activity in primary cultures from the O. masou brain is mainly connected with the suspension fraction of small cells. In contrast, a positive correlation between the cells expressing cystathionine β-synthase (CBS), a marker of H2S synthesis, and the cells expressing PCNA in the monolayer, indicates the participation of H2S in proliferative activity of neurons in primary cultures. The data obtained suggest that the hydrogen sulphide is also involved in the process of differentiation.

Preliminary Evaluation of Soils from Kwalkwalawa （Sokoto） and Bakolori （Talata Mafara） Regions Used for Rice and Fishing Activities

Kwalkwalawa is an area noted for extensive rice production and fishing activities, while Talata Mafara is a site used mainly for rice production. Soils of the two areas were taken and evaluated for potentialities of rice-cum-fish culture. Three replicate soil samples were collected in October 2004 and 2005 from three sampling sites within the study area at 0-15 cm and 15-30 cm depth. Analysis of the samples indicated that at Kwalkwalawa the soil pH was 7.35 and 7.28 for 0-15 cm and 15-30 cm depth, respectively, and 6.75 and 6.67 for Talata Mafara, respectively, during 2004. During 2005, the pH at Kwalkwalawa was 6.75 and 7.18, while at Talata Mafara ranged between 5.63 and 5.14. Organic carbon content at Kwalkwalawa estimated during 2004 was 1.12 g/kg and 0.81 g/kg for 0-15 cm and 15-30 cm, whereas at Talata Mafara amounted 0.93 g/kg and 0.11 g/kg. During 2005, noted values of organic carbon at Kwalkwalawa lowered to 0.45-0.28 g/kg and at Talata Mafara lowered to 0.38-0.06 g/kg. Total nitrogen （N） at Kwalkwalawa during 2004 was 0.04 g/kg and 0.03 g/kg for 0-15 cm and 15-30 cm, at Talata Mafara it was both 0.04 g/kg for both depths. During 2005, at Kwalkwalawa, total N was 0.04 g/kg and 0.03 g/kg, and at Talata Mafara it was 0.05 g/kg for both depths. Available phosphorus （P） at Kwalkwalawa during 2004 was 1.93 mg/kg and 2.03 mg/kg for 0-15 cm and 15-30 cm, at Talata Mafara it was 1.59 mg/kg and 1.63 mg/kg. During 2005, available P was 5.82 mg/kg and 6.13 mg/kg for Kwalkwalawa and 1.67 mg/kg and 1.91 mg/kg for Talata Mafara, at 0-15 cm and 15-30 cm, respectively. Analysis of clay content indicated that at Kwalkwalawa the clay content was 11 g/kg for both depths during 2004 and 16.5 g/kg during 2005, and the soil texture was classified as sandy loam during both seasons. At Talata Mafara during 2004, the clay content was 73 g/kg and 93 g/kg for 0-15 cm and 15-30 cm. During 2005, it was 84 g/kg and 103 g/Kg. The soil was classified as loamy sand after fitting it into textural triangle. Results indicated the clay content at Kwalkwalawa over two seasons was stable, but at Talata Mafara it differed, even though the soil texture was the same for both seasons and sampling depths. The results showed that with some textural improvements, rice-cum-fish culture project can be undertaken in the study areas.

The Importance of Hunting and Hunting Areas for Big and Small Game （Food） for the Tourism Development in the Crna River Basin in the Republic of Macedonia

The Crna River is a river in the Republic of Macedonia, right tributary to Vardar. Its source is in the mountains of Western Macedonia, west of Krusevo. It flows through the village of Sopotnica, and southwards through the plains east of Bitola. The name means ＂black river＂ in Macedonian, which is translation for its former Thracian name. The purpose of this paper is to show the hunting and hunting areas for big and small Game （food）, the structure of the areas of certain hunting, fishing, fishing water objects, fish species, fishponds up to 20 years shown by municipalities and individual farms with ponds in the basin of Black River. It had used statistical data for the hunting grounds by areas, fishing ponds. Fish is very diverse in this river. Hunting in the Black River basin is of great importance for the economy of Republic of Macedonia. It is also a necessary factor for development of other economic activities.

Effect of Dietary Lipid Levels on Fatty Acids Composition of Cultured Sparusaurata

The aim of this study was to determine the progressive evolution of fish muscle fatty acids composition feeding by different lipid levels of farmed Mediterranean gilthead sea bream （Sparusaurata）. During twenty one weeks, Sparusaurata were hand-feed two diets with protein and lipid ratios 47/20 （Diet A） and 45/22 （Diet B） respectively. At the end of the feeding period, lipid contents of muscle, as well as fatty acids profiles of different portions of the muscles were studied. Results indicated the effects of fatty acids profiles of diets throughout the liver and white muscle fillet （dorsal, middle and ventral）. These were more noticeable when Sparusaurata was fed on the diet Athat decreased the content of monounsaturated fatty acids （MUFA）, and polyunsaturated fatty acids （PUFA） in all the muscles during the period of feeding while the saturated fatty acids （SFA） content tended to increase and it was lower than ones in the muscles of Sparusaurata fed on diet B. The highest amount of PUFA and docosahexaenoic acid, （22：6n-3 DHA） were found among the different portions of ventral muscles. In addition, the progressive evolution of different parts of muscle＇s fatty acid profiles showed significant differences in contents of SFA, PUFA and especially the n-3 PUFA. However, the content of MUFA seems to be alike in different muscles and tended to decrease in dorsal and ventral muscle from Do to Df and inversely when the fish were fed on diet A.

Analysis and Evaluation of Nutrient Composition in the Wild, Pond- and Lake-Cultured Topmouth Culter (Culter alburnus)

Research was conducted on topmouth culter (Culter alburnus) grown in ponds and lakes as well as wild types in order to determine their chemical composition and nutritional value. There are three types of fish that differ in their proximate composition, amino acids, fatty acids, and minerals. Wild fish had a significantly lower crude lipid contents than cultured fish (P P ∑PUFAs) showed an obviously opposite trend. As compared with cultured fish, wild fish had significantly higher levels of n-3 PUFAs, arachidonic acid (AA), eicosapentaenoic acid (EPA) and docosahxaenoic acid (DHA) (P P > 0.05), except for Na, Fe and Se. In conclusion, diet composition and external aqueous environment may determine the differences between wild and cultured topmouth culter.

Assessment of Fish Farming Practices, Operations, Water Resource Management and Profitability in Katsina State, Nigeria

This study assessed the fish production, culture facilities, operations, water resource management and profitability of fish farming in Katsina State, Nigeria, with a view of understanding the status of aquaculture development in Katsina State. Data were collected using structured questionnaire administered to 35 out of the active 42 farms in Katsina State at the period and the data obtained were analyzed using descriptive statistics and linear regression. Among the respondents, 37.1% used concrete tank alone and another 37.2% used concrete tank with other types of culture facilities, 57.1% practised mono-culture techniques and 77.1% used stagnant renewal system as culture system. Management of water quality was done by majority(82.9%) with mere visual evaluation, while 68.6% did not use any forms of water treatment. Most of the farms(80%) depended on imported feed for feeding their fish and gross profits of ■7.29±1.81 and ■157.83±118.08 were obtained on fingerlings and adult fish, respectively. The tested explanatory variables were responsible for 45.4% change in profitability and profitability was found to be dependent on feeding cost(t=–3.38 and p=0.002) and size of fish at harvest(t=2.70 and p=0.011). The research findings established that fish farming in Katsina State was under developed.

Fish Nutrition Additives in SHK-1 Cells: Protective Effects of Silymarin

In nutrition for productive species, additives play an important role in boosting physiological processes. Only in recent years studies include models of the effects on fish cells of these additives. We observed effects of silymarin, a compound highly utilized in aquaculture. The cell line SHK-1 was used derived from the upper liver of the Atlantic salmon as a biological model. Samples were exposed to silymarin in incrementing time and concentrations, to evaluate by MTT and number of cells, the effects on cell viability. Also, oxidative stress models were used to find the protector effects of silymarin against these agents. Our data indicate that a dose of 100 ppm of silymarin is sufficient to stimulate cellular proliferation. Cultures were exposed to high glucose (15 mM) or H2O2 (0.1 mM) in presence of or absence of silymarin at 100 ppm. We observed that the toxic effects of both compounds were blocked by the presence of silymarin. Our results indicate that it is important to evaluate additive effects at a cellular level. Also, silymarin does have proliferative effects, and protect against cellular injury in our models. Our study helps to generate more rational applications of additives in the industry and presents new challenges in order to better manipulate the model in the laboratory, allowing us to obtain new evidence regarding the microalgae’s biology through in vitro studies.

Characteristics of Growth and Yield Formation of Rice in Rice-Fish Farming System

By using single rice cultivation as a control, the effect of rice-fish culture on growth dynamic, plant type and yield formation of rice was studied. The results showed as follows： rice-fish culture improved the physical-chemical properties of arable layer soil of paddy field, extended growth period of rice, increased dry matter and LAI of different growth stages, improved three top leaves area, deterred the degeneration of leaves function, increased the diameter of stem, promoted the growth of roots and the formation of roots in the extended stem. At the same time, rice-fish culture extended the length of basal internodes, increased the number of internodes, uplifted the gravity of plant, and depressed the root vigor. For the grain yield and yield structure office, rice-fish culture decreased ear/tillering ratio, spikelet/panicle and seed set percentage, increased grain weight. If variety choice and cultivation technology were controlled appropriately, rice-fish culture could increase the effective panicles and improve grain yield of rice.

Effects of Temperature upon Water Turnover in Fish Ponds in Northern Thailand

Fish culture in earthen ponds is an important source of income for farmers in northern Thailand. Water quality in ponds has strong impacts on fish production farmers’ return and is sensitive to weather and climate. Low levels of dissolved oxygen in fish ponds are major cause of mass mortality. Stratification with depth in ponds followed by rapid turnover or exchange of surface and bottom water can expose fish to dangerously low dissolved oxygen levels. The main purpose of this study was to observe the effects of weather on stratification and subsequent water turnover in fish ponds in northern Thailand, especially in the winter and rainy season, when stratification was expected to be most severe. Temperature and water quality measurements were made in fish ponds at 18 farms with depths ranged from 0.8-2.0 m and size of 0.16-0.64 ha. Measurements were made during January and May 2013. Fish farm pond sites were divided into two groups based on elevation above sea level: low (400 masl) and categorized into 3 types of farming: commercial, integrated and subsistence. In lower elevation sites, water turnover occurred at night between 22.00 and 02.00 in winter and between 18.00 and 02.00 in rainy season. At higher elevation, turnover occurred in ponds between 20.00 and 22.00 in winter and between 14.00 and 18.00 in rainy season. Turnover was slower in the lower elevation than in higher elevation zones and generally occurred earlier during the rainy season than in the winter. Mean DO in winter was significantly higher (p<0.05) than in rainy season, whilst water temperature and amount of ammonia-nitrogen during the rainy season was significantly higher (p<0.05) than in winter. Turnover improves distribution of dissolved oxygen through the water column and minimizes organic matter accumulation. Cloud cover during the rainy season may have contributed to limit oxygen production and thus may have significantly affect water quality in ponds. Fish farmers should consider more explicitly the role of temperature and cloud conditions when managing dissolved oxygen levels in their fish ponds. Therefore, efficient pond aeration or pond mixing strategies for reducing stratification still plays an important component for providing sound pond management in tilapia production ponds.

Improving Production of Zebra Fish Embryos in the Lab

The utilization of fish embryos in toxicity testing of hazardous chemicals has recently been adopted in order to satisfy stricter rules and regulations related to using adult animals in toxicity testing. This paper presents optimising steps towards improving zebra fish embryo production in the laboratory. Culture conditions were maintained in the aquaria as stipulated in the OECD draft proposal for a new guideline on fish embryo tests. Furthermore, a sequence of steps were adopted and followed to improve upon previous work done in the lab in 2006. About 200 eggs were produced in one spawn trap within an hour of onset of light, an improvement over the 50 - 60 eggs produced in the previous work. This result demonstrates that with the right culture conditions and proper optimisation of procedure the required number of embryos needed for toxicity testing can be obtained.