Rocky reef fish biodiversity and conservation in a Brazilian Hope Spot region

Abstract Coastal islands of Grande Rio, located south Rio de Janeiro and Maricá cities have been under multiple anthropogenic impacts. Despite these problems, these insular systems shelter a high diversity of fish species. Reef fishes are essential components of tropical marine coastal communities, also providing food and income for millions of people around the world. In this work, we generated an updated checklist from Cagarras Islands Natural Monument and surrounding areas based on fisheries data, literature records and multiple sampling techniques, including the Submersible Rotating Video technique, used for the first time in Brazil. We present an inventory of 282 fish species representing 91 different families, with 21 new records for the study area, including a non-native species (Heniochus acuminatus). In addition, our results show a moderate endemism level for the Brazilian province (approximately 6.0%), while 10.5% of species are assigned to one of IUCN’s threatened categories. Our efforts show the fish biodiversity scenario and their distribution on coastal islands more than 10 years after the Cagarras Islands Natural Monument establishment, reinforcing the importance of monitoring research programs for the management of this Marine Protected Area and surrounding waters, that play a key role for artisanal fisheries.

摘要：位于里约热内卢州南部与马里卡（Maricá）两市辖区内的格兰德里奥（Grande Rio）沿岸群岛，长期遭受多重人为活动的干扰与破坏。尽管面临上述生态压力，该岛群仍孕育着高度丰富的鱼类物种多样性。礁栖鱼类是热带海洋沿岸群落的核心组成部分，同时为全球数百万民众提供食物与收入来源。本研究基于渔业调查数据、文献记录与多种采样手段，包括首次在巴西应用的水下旋转视频采样技术（Submersible Rotating Video technique），对卡加拉什群岛自然保护区（Cagarras Islands Natural Monument）及其周边海域的鱼类物种开展了更新版名录编制工作。本研究共收录隶属于91个科的282种鱼类，其中21种为该研究区域的新记录物种，包含1种外来物种——马夫鱼（Heniochus acuminatus）。此外，研究结果显示该区域鱼类在巴西海洋生物地理区中的特有种占比约为6.0%，另有10.5%的物种被纳入世界自然保护联盟（International Union for Conservation of Nature，简称IUCN）的受威胁等级范畴。本研究明确了卡加拉什群岛自然保护区设立十余年之后的沿岸岛屿鱼类生物多样性现状与分布格局，进一步证实了长期监测研究计划对该海洋保护区（Marine Protected Area）及其周边海域管理的重要性——该海域对小型手工渔业的发展具有关键支撑作用。