Experiments were carried out in fall and winter, 1990
and spring and summer, 1991 , to determine growth and
mortality of juvenile Pacific oysters {Crassostrea gigas)
in effluent from cultured coho salmon {Oncorhynchus
kisutch) , and effluent from salmon in which the red
macroalga Palmaria mollis was cultured. Ambient sea water
from Yaquina Bay was used as a control. Juvenile Manila
clams {Tapes japonica) were also tested in summer, to
compare the growth response of clams with that of Pacific
oysters. Measured growth parameters included: increase in
mean individual live weight, specific growth rate (%
increase of mean live weight per day) and mean individual
organic (ash-free) weight. Temperature, chlorophyll a,
phaeopigment, carbon and nitrogen concentrations and C/N
ratio for all treatments were also recorded during spring
and summer, 1991.
The oysters grew significantly faster in effluent
from salmon and salmon conditioned by macroalgae than in
the control during the Fall Experiment (September 7-
0ctober 31, 1990). Mean water temperature was 13-16°C.
Growth rates were significantly greater in oysters
cultured in salmon effluent than in the control during the
Winter Experiment (December 7, 1990-February 15, 1991).
However, growth was very poor due to low water
temperatures (7-10°C).
Growth of oysters was significantly greater in the
control than in effluent from salmon and salmon
conditioned by macrolagae in the Spring Experiment (March
7-May 24, 1991). Mean water temperature was 12°C. In the
Summer Experiments, (June 3-July 4 and July 19-August 17,
1991) growth of oysters was more rapid in treatments with
macroalgae as compared to treatments without macroalgae
Comparative experiments with juvenile Manila clams gave
similar results.
Percentage mortality for both oysters and clams
ranged from 0 to 5% and was highest during winter and
lowest during summer. Mean chlorophyll values ranged from
1 μg/1 in spring, 1991 to 11 μg/1 summer, 1991. / Graduation date: 1992
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/37182 |
| Date | 03 March 1992 |
| Creators | Diaz, Maria Elena, 1958- |
| Contributors | McNeil, William J. |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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