Record Details
Field | Value |
---|---|
Title | Land-based polyculture of chinook salmon, Oncorhynchus tshawytscha; Manila clams, Tapes japonica (Deshyes); and red macroalgae, Palmaria mollis |
Names |
Moosapanah, G. Reza
(creator) McNeil, William J. (advisor) |
Date Issued | 1996-04-05 (iso8601) |
Note | Graduation date: 1996 |
Abstract | This investigation demonstrates the feasibility of a polyculture system using effluent water from land-based salmon culture systems to feed juvenile Manila clams, Tapes japonica (Deshyes), and an evaluation of an artificial diet for feeding juvenile clams. An economic analysis of the polyculture system was compared to cultures of a single species. Growth and survival of Manila clams were compared in salmon effluent, salmon plus red macroalgae, Palmaria mollis, effluent, and ambient water from an estuary. Manila clam growth and survival were similar under the two polyculture conditions but significantly lower in ambient bay water. Growth and survival of various biomasses and sizes of juvenile Manila clams receiving effluent water from salmon were compared in a second experiment. Growth in the treatment having the lowest biomass and smallest size of clams was significantly higher than in the other treatments. The effects of fish feed at different concentrations on growth and survival of juvenile Manila clams were evaluated in the third and fourth sets of experiments. These experiments indicated that fish feed alone stimulates growth which maintaining high survival at food concentrations which were neither too high nor too low. A fifth experiment evaluated growth and survival of juvenile Manila clams suspended in a salmon culture tank. Growth rates were the same at different depths. A final experiment evaluated the importance of dissolved and particulate by-products of fish food in the size range of 50 -0.2 microns on growth and survival of juvenile Manila clams. Particles equal to or less than 2.0 microns were not sufficiently utilized by clams to contribute to growth. The 50 micron food particles produced the highest growth. Economic analyses compared a salmon/clam polyculture system with a salmon monoculture and two clam monoculure systems. Salmon monoculture proved to be uneconomic at prevailing market prices. Addition of Manila clams to this system appeard to be a profitable prospect. Monoculture of Manila clams was unprofitable with the current industrial practice of feeding cultured microalgae. However, clam monoculture fed with a commercial salmon diet was marginally profitable. |
Genre | Thesis |
Topic | Aquaculture |
Identifier | http://hdl.handle.net/1957/10082 |