館山湾坂田におけるベラ科オハグロベラの産卵期と非産卵期における生息場所

千葉県館山市坂田海岸においてベラ科オハグロベラの産卵期と非産卵期における雌雄の生息場所を観察した．本種の産卵期は6月から8月までである．産卵期(6月 ～ 8月）および非産卵期（5月，9月 ～ 12月）の各月に，産卵場から岸に向かって100 mのラインを引き, そのライン上を20 mごとに区切った1から6の地点を調査地点における雌雄の個体数を調査した．産卵期は雌雄共に産卵場付近に個体数が多かった．非産卵期になると雌は岸寄りに移動したが，雄は出現場所に偏りが無かった．出現個体数は，雌では産卵期・非産卵期共に差はなかったが，雄では非産卵期になると減少したHabitat of the wrasse Pteragogus aurigarius was studied in both spawning and non-spawning seasons at Banda Beach, Tateyama, Japan. Spawning season of this species is from June to August. Once a month in spawning (June to August) and non-spawning (May, September to December) seasons, we counted number of female and male individuals in six points by 20 m interval along the 100 m line set on the bottom from the spawning site to seashore. Both female and male were abundant near the spawning site in the spawning season. In the non-spawning season, number of female individuals increased near seashore, while the males evenly distributed. Although there was no significant difference in number of female individuals between spawning and non-spawning seasons, those of the males had decreased in non-spawning season.Shuta ENDO(Corresponding author), Sayo TOMATSU and Tomoki SUNOBE: Laboratory of Fish Behavioral Ecology, Tateyama Station, Field Science Center, Tokyo University of Marine Science and Technology (TUMSAT)遠藤 周太・戸松 紗代・須之部 友基: 東京海洋大学館山ステーション魚類行動生態学研究室Shuta ENDO: Tokyo Sea Life Park遠藤 周太: 葛西臨海水族

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