Consideraciones biológicas de Choromytilus chorus en dos sustratos diferentes
DOI:
https://doi.org/10.21703/0067-8767.1971.5.2385Abstract
The mussel population (Choromytilus chorus) in the mussel culture station of Putemún in the Castro Estuary was analyzed. A study of mussels grown from rafts and mussels grown on a natural bottom or bank was made. Between August, 1968 and April, 1970 monthly data was collected to compare the sexual maturity, the spawning and the rate of growth between the two groups of mussels.
The following results were obtained:
The sizes of the mussels varied between 12 and 112 mm in length for mussels from the floating raft culture and 106.6 to 160 mm in individuals collected from the natural bank.
The weight of the edible parts increased proportionally according to the mussel’s length. The data collected is very similar for males and females.
Although the overall size was larger in mussels collected from the natural bank, the weight of the edible parts increased more rapidly in examples taken from the raft culture system. Examples of over 100 mm in length exhibit weight values considerably larger for raft cultured mussels than in natural bank mussels.
The weight of edible material represented 43.3% of the total weight in raft cultured mussels, but only 31.3% for natural bank mussels.
The mussels exhibit separate sexes, but the different sexes are distinguishable only when mussels reach sexual maturity during the spawning seasons.
The average diameter of an ovule is 52 microns. The head of an espermatozoid has an average maximum diameter of 3.18 microns.
Spawning individuals are found between the end of September until January. Spawning is heaviest during the month of November.
The greater percentages of spawning individuals are found in samples of raft cultured mussels. These mussels located near the surface of the estuary grow in a more favorable environment containing abundant food, adequate temperatures and a suitable substrate for the attachment of young mussels.
The rapid growth of mussels cultivated from floating rafts is notoriously greater than the growth of mussels grown on a natural bottom. Raft culture mussels reach a commercial size at approximately 4 years of age.
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