Budget Amount *help |
¥5,200,000 (Direct Cost: ¥4,000,000、Indirect Cost: ¥1,200,000)
Fiscal Year 2015: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
Fiscal Year 2014: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
Fiscal Year 2013: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
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Outline of Final Research Achievements |
Although fishing activity often targets only males or females, little is known about the effects of harvesting biased to one sex on population dynamics in commercial species. This study examined the relationship between breeding sex ratio and reproductive success of a shrimp population that only females were harvested. This study showed that male-biased sex ratio (1) increases the number of males that do not have mating opportunity, (2) tends to decrease in genetic diversity of the population, and (3) intensifies copulation attempt by males and depresses female fertility. These results suggest that sex-selective harvesting can decrease reproductive successes of both male and female of target species.
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