Brenes C L, Hernández A, Campos J
Laboratorio de Oceanografía y Manejo Costero Universidad Nacional, Heredia, Costa Rica, Apdo 86-3000.
Rev Biol Trop. 2000 Jun-Sep;48(2-3):399-411.
Between August 1995 and August 1997 long line fishing techniques and a bathythermograph were used to correlate some physical variables with the spatial distribution of four shark species in 26 fishing cruises off the Nicaraguan Pacific Coast. They were the thresher (Alopias vulpinus), blue (Prionace glaucea), gray (Carcharhinus falciformis) and hammer (Sphyra lewini). All species concentrated in the southeastern Nicaraguan Pacific, at the seasonal upwelling area of Papagayo Gulf. The range of sea surface temperatures in which the sharks were captured was 25-28 degrees C. We could clearly associate this physical parameter with shark availability. The vertical distribution of the captured sharks suggests that they occupy termocline levels above the 15 degrees C isotherm. Although these species are oceanic, the blue shark was captured in ocean waters over the 1800 m isobar, while the grey and thresher sharks where close to the continental shelf. Body length in decreasing order are: thresher (210-290 cm, SN = 21), blue (60-240 cm, SN = 13) and gray (80-200 cm, SN = 17).
1995年8月至1997年8月期间,在尼加拉瓜太平洋海岸外的26次捕鱼航行中,使用延绳钓技术和温深仪将一些物理变量与四种鲨鱼的空间分布相关联。它们是长尾鲨(狐形长尾鲨)、蓝鲨(大青鲨)、灰鲨(镰状真鲨)和锤头鲨(路氏双髻鲨)。所有物种都集中在尼加拉瓜太平洋东南部,帕帕加约湾的季节性上升流区域。捕获鲨鱼的海面温度范围为25-28摄氏度。我们可以清楚地将这个物理参数与鲨鱼的可捕量联系起来。捕获鲨鱼的垂直分布表明它们占据了15摄氏度等温线以上的温跃层。虽然这些物种是大洋性的,但蓝鲨是在等深线1800米以上的海域捕获的,而灰鲨和长尾鲨则靠近大陆架。体长从大到小依次为:长尾鲨(210-290厘米,样本数=21)、蓝鲨(60-240厘米,样本数=13)和灰鲨(80-200厘米,样本数=17)。