Feeding experiments and some aspects of the biology of the sand shrimp, Crangan septemspinosa, in Long Pond, Newfoundland
Laboratory experiments were conducted to investigate the effect of fresh or frozen foods of marine origin on the growth and survival of the sand shrimp, Crangon septemspinosa, under constant temperature conditions. The diets tested were blue mussel, squid, capelin, and TetraMin, alone and in combina...
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| Format: | Thesis |
| Language: | English |
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Memorial University of Newfoundland
1978
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| Online Access: | https://research.library.mun.ca/7776/ https://research.library.mun.ca/7776/1/Hadiistephanou_NicosA.pdf https://research.library.mun.ca/7776/3/Hadiistephanou_NicosA.pdf |
| Summary: | Laboratory experiments were conducted to investigate the effect of fresh or frozen foods of marine origin on the growth and survival of the sand shrimp, Crangon septemspinosa, under constant temperature conditions. The diets tested were blue mussel, squid, capelin, and TetraMin, alone and in combination. -- Shrimp grew best on mussel and mussel combined diets and, less well on squid and its combinations with fish and TetraMin. The poorest growth was observed with TetraMin and its combination with fish. Moulting intervals, overall growth rates, and the survival of the sand shrimp, were all correlated with the diets. -- Amino acid analyses showed the closest similarity between mussel and the shrimp; TetraMin had the least similarities, and squid and capelin were intermediate. Thus, differences in the growth and survival could be attributed to the amino acid content of the diets. -- Substrate particle size and colour selection experiments showed that Crangon septemepinosa prefer sand to burrow in and reject substrate with particles bigger than 2 mm. The sand shrimp selected brown substrates and avoided the white ones. -- In Long Pond, Newfoundland, a size difference was apparent between males and females. Juveniles were collected in almost all the collections and were most numerous in August. Egg-carrying females appeared from April to August. The first egg-carriers were large females; in July smaller shrimp were carrying eggs. Egg-carrying females were not collected in September and are presumed to have moved into deeper waters. -- The mode of appearance of the populations segments suggests an extended breeding season. Egg-carrying females exist for 11-12 months, migrating into deeper water with the progress of the egg development. Migration of the bigger animals takes place with the cooling of the waters and inshore migration, with the increase of the temperature. |
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