Some Parameters of the Population Biology of Spotted Flounder (Citharus linguatula Linnaeus, 1758) in Edremit Bay (North Aegean Sea)
A total of 1096 spotted flounder (Citharus linguatula Linnaeus, 1758) were caught in Edremit Bay from September 1998 to September 2000. Length-weight relationships, age, growth, mortality and sex ratio of the samples were investigated. Within the population of this species, most of the individuals in our samples ranged from 100 to 160 mm (69.63%), the minimum and maximum total lengths of the specimens being 69 and 222 mm, respectively. Positive allometric growth was observed for male, female and all fish. Age distribution of the samples was from I to IV. There was no significant difference between observed and calculated (von Bertalanffy and back calculation) average total lengths of the age groups (P > 0.05). The sex ratio (females:males) was 1:1.27. The total (Z), natural (M) and fishing mortality (F) rates, and the exploitation ratio (E) for all individuals were estimated respectively as Z = 0.60, M = 0.75, F = 0.15 and E = 0.25. This shows that the spotted flounder stock of Edremit Bay is being exploited at a lower than optimal level.
Some Parameters of the Population Biology of Spotted Flounder (Citharus linguatula Linnaeus, 1758) in Edremit Bay (North Aegean Sea)
A total of 1096 spotted flounder (Citharus linguatula Linnaeus, 1758) were caught in Edremit Bay from September 1998 to September 2000. Length-weight relationships, age, growth, mortality and sex ratio of the samples were investigated. Within the population of this species, most of the individuals in our samples ranged from 100 to 160 mm (69.63%), the minimum and maximum total lengths of the specimens being 69 and 222 mm, respectively. Positive allometric growth was observed for male, female and all fish. Age distribution of the samples was from I to IV. There was no significant difference between observed and calculated (von Bertalanffy and back calculation) average total lengths of the age groups (P > 0.05). The sex ratio (females:males) was 1:1.27. The total (Z), natural (M) and fishing mortality (F) rates, and the exploitation ratio (E) for all individuals were estimated respectively as Z = 0.60, M = 0.75, F = 0.15 and E = 0.25. This shows that the spotted flounder stock of Edremit Bay is being exploited at a lower than optimal level.
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