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Low Salinity Waters (low + salinity_water)
Selected AbstractsGrowth and movement patterns of early juvenile European anchovy (Engraulis encrasicolus L.) in the Bay of Biscay based on otolith microstructure and chemistryFISHERIES OCEANOGRAPHY, Issue 3 2010NAROA ALDANONDO Abstract Various hypotheses have been put forward to explain the mechanisms in the Bay of Biscay that result in a good recruitment of European anchovy. Anchovy larvae from the spawning area in the Gironde River plume are advected towards off-shelf waters, where juveniles are commonly observed. Otolith microstructural and chemical analysis were combined to assess the importance of this off-shelf transport and to determine the relative contribution of these areas for anchovy survival. Chemical analysis of otoliths showed that anchovy juveniles in the Bay of Biscay can be divided into two groups: a group that drifts towards off-shelf waters early in their life and returns later, and a group that remains in the low salinity waters of the coastal area. The first group presents significantly faster growth rates (0.88 mm day,1) than those remaining in the coastal waters (0.32 mm day,1). This may be due to off-shelf waters being warmer in spring/summer, and to the fact that the lower food concentration is compensated for by higher prey visibility. Furthermore, the group of juveniles that drifted off the spawning area and had faster growth rates represents 99% of the juvenile population. These findings support the hypothesis that anchovy in the Bay of Biscay may use off-shelf waters as a spatio-temporal loophole, suggesting that transport off the shelf may be favourable for recruitment. [source] Demonstration of alternative feeds for the Pacific white shrimp, Litopenaeus vannamei, reared in low salinity waters of west AlabamaAQUACULTURE RESEARCH, Issue 4 2009Luke A Roy Abstract The replacement of marine proteins with vegetable proteins or terrestrial animal byproducts in aquaculture diets has been gaining momentum. This study examines the viability of replacing fish meal in shrimp production diets with alternative protein sources (combinations of vegetable proteins) in inland low salinity waters of west Alabama. The test diets were formulated to contain 36% protein and 8% lipid. The basal diet contained 10% fish meal. The fish meal was then replaced (on a weight to weight basis) with poultry meal (PM), pea meal or distiller's dried grain with solubles (DDGS). Two separate experiments (laboratory trial and farm trial) were devised to test the efficacy of the diets for Litopenaeus vannamei reared in low salinity waters. The laboratory trial was conducted at the E. W. Shell Fisheries Research Station in Auburn, Alabama, USA, whereas the farm trial examined the same diets in an outdoor flow-through system at a low salinity shrimp farm in west Alabama. Results indicate no significant differences in shrimp growth, weight gain, survival or feed conversion ratio among dietary treatments, suggesting that PM, pea meal and DDGS can serve as alternatives to fish meal as a protein source for shrimp reared in low salinity environments. [source] |