Khalaf Maroof A, Abdallah Mohamed
The University of Jordan, Department of Marine Biology, Faculty of Marine Sciences, P. O. Box 195, Aqaba, Jordan.
Fishery resources expert, Ministry of Environment, P. O. Box: 8703, Doha, State of Qatar.
Zookeys. 2014 Jan 6(367):33-64. doi: 10.3897/zookeys.367.5476. eCollection 2014.
The spatial distribution of 50 ornamental fish species from shallow water habitats on coral reefs were investigated using visual census techniques, between latitudes 11-29°N in the Red Sea, in Jordan, Egypt, Saudi Arabia, and Yemen, and in the adjacent Gulf of Aden in Djibouti. One hundred eighteen transects (each 100×5 m) were examined in 29 sites (3-8 sites per country). A total of 522,523 fish individuals were counted during this survey, with mean abundance of 4428.2 ± 87.26 individual per 500 m² transect. In terms of relative abundance (RA), the most abundant species were Blue green damselfish, Chromis viridis (RA=54.4%),followed bySea goldie, Pseudanthias squamipinnis (RA= 34.7), Whitetail dascyllus, Dascyllus aruanus (RA= 2.6%), Marginate dascyllus, Dascyllus marginatus (RA= 2.0),Red Sea eightline flasher Paracheilinus octotaenia (RA=1.0),andKlunzinger's wrasse, Thalassoma rueppellii (0.7%). The highest number of species (S) per 500 m² transect was found on reefs at the latitude 20° in Saudi Arabia (S=21.8), and the lowest number of species was found at the latitude 15° in Djibouti (S=11.11). The highest mean abundance (8565.8) was found on reefs at latitude 20° in Saudi Arabia and the lowest mean abundance (230) was found on reefs at latitude 22°, also in Saudi Arabia. Whereas, the highest Shannon-Wiener Diversity Index was found in reefs at the latitude 22° (H=2.4) and the lowest was found in reefs at the latitude 20° (H=0.6). This study revealed marked differences in the structure of ornamental fish assemblages with latitudinal distribution. The data support the presence of two major biogeographic groups of fishes in the Red Sea and Gulf of Aden: the southern Red Sea and Gulf of Aden group and the group in the northern and central Red Sea. Strong correlations were found between live coral cover and the number of fish species, abundance and Shannon-Wiener Diversity indices, and the strength of these correlations varied among the reefs. A conclusion was done that environmental differences among the reefs and the habitats investigated were important components of abundance variations and species diversity of ornamental fish along latitudinal gradients in the Red Sea and the Gulf of Aden.
利用视觉普查技术，对红海北纬11 - 29°之间约旦、埃及、沙特阿拉伯和也门浅海珊瑚礁栖息地的50种观赏鱼的空间分布进行了调查，同时也调查了吉布提附近亚丁湾的情况。在29个地点（每个国家3 - 8个地点）检查了118条样带（每条100×5米）。在这次调查中共计数了522,523条鱼，每500平方米样带的平均丰度为4428.2±87.26条。就相对丰度（RA）而言，最丰富的物种是蓝绿光雀鲷（Chromis viridis，RA = 54.4%），其次是金背拟花鮨（Pseudanthias squamipinnis，RA = 34.7%）、白尾宅泥鱼（Dascyllus aruanus，RA = 2.6%）、缘边宅泥鱼（Dascyllus marginatus，RA = 2.0%）、红海八线闪龙（Paracheilinus octotaenia，RA = 1.0%）和鲁氏锦鱼（Thalassoma rueppellii，0.7%）。每500平方米样带物种数量最多（S）的是沙特阿拉伯纬度20°的珊瑚礁（S = 21.8），物种数量最少的是吉布提纬度15°的珊瑚礁（S = 11.11）。平均丰度最高（8565.8）的是沙特阿拉伯纬度20°的珊瑚礁，平均丰度最低（230）的也是沙特阿拉伯纬度22°的珊瑚礁。然而，香农 - 维纳多样性指数最高的是纬度22°的珊瑚礁（H = 2.4），最低的是纬度20°的珊瑚礁（H = 0.6）。这项研究揭示了观赏鱼组合结构在纬度分布上存在显著差异。数据支持红海和亚丁湾存在两个主要的鱼类生物地理群：红海南部和亚丁湾群以及红海北部和中部群。发现活珊瑚覆盖率与鱼类物种数量、丰度和香农 - 维纳多样性指数之间存在强相关性，并且这些相关性的强度在不同珊瑚礁之间有所不同。得出的结论是，所调查的珊瑚礁和栖息地之间的环境差异是红海和亚丁湾沿纬度梯度观赏鱼丰度变化和物种多样性的重要组成部分。
