Many elasmobranch species utilize estuaries as nurseries, parturition areas, and foraging grounds. Florida’s Indian River Lagoon (IRL), an “estuary of national significance,” has experienced many anthropogenic impacts in recent decades, such as habitat degradation and declining water quality, and there is a substantial data gap surrounding the status of elasmobranchs in this system. A fishery-independent survey (longline/gillnet) was implemented to characterize the elasmobranch community and understand distribution patterns and habitat use in the IRL (Sebastian to St. Lucie Inlet). From July 2016 to June 2018, 630 individuals of 16 species were caught and tagged, including two critically endangered smalltooth sawfish Pristis pectinata. Bull sharks Carcharhinus leucas and Atlantic stingrays Hypanus sabinus were the two most common species collected (47% of the total catch), and size differences by region were observed. The longline catch exhibited a significant difference in species composition among regions while the gillnet catch composition significantly varied among seasons. Although dependent on survey gear type, there was evidence of combinations of abiotic parameters (e.g., depth, salinity, water clarity, distance to a freshwater source, distance to an inlet) driving elasmobranch species composition. Bull sharks and Atlantic stingrays dominated areas with frequently low salinities while more diverse assemblages of species were apparent towards inlet passes. This study provides the first in-depth analysis of the elasmobranch community in the IRL and develops capacity to understand how these species may respond to further environmental changes in this highly impacted estuary.

许多弹性分支物种利用河口作为苗圃，分娩区和觅食场。佛罗里达的印度河泻湖（IRL）是“具有重要意义的河口”，近几十年来经历了许多人为影响，例如栖息地退化和水质下降，并且该系统中的弹性支流状况存在巨大的数据空白。进行了一项与渔业无关的调查（延绳钓/刺网），以表征弹枝支流群落的特征，并了解IRL（从塞巴斯蒂安到圣露西湾）的分布模式和栖息地使用情况。从2016年7月到2018年6月，共捕获并标记了16种630个个体，其中包括两个极度濒临灭绝的小齿锯齿普里斯提斯。公牛鲨真鲨和大西洋黄貂鱼Hypanus sabinus是收集到的两种最常见的物种（占总捕获量的47％），并且观察到了区域之间的大小差异。延绳钓渔获物在区域间的物种组成上存在显着差异，而刺网渔获物的组成随季节而显着变化。尽管取决于调查设备的类型，但有证据表明非生物参数（例如，深度，盐度，水的透明度，与淡水源的距离，与进水口的距离）的组合会驱动弹性分支物种的组成。公牛鲨和大西洋黄貂鱼通常是盐度较低的地区，而在进水口则明显有更多种类的物种。