This study focused on the distribution of fish with high reproductive activity along a basin, using a 430 km stretch of the Cuiabá River in Brazil as a model. The main objective was to identify those fish that migrate long distances for reproduction, among all the basin species. Thus, a set of working criteria is proposed to classify species according to their reproductive behaviour (i.e., reproductive activity and distribution). Samplings were performed in the Cuiabá River basin, encompassing several environments (river, channels and lakes) during the reproductive periods (between October and February), from 2000 to 2004. Species occurrence (presence and absence - proxy of distribution) across the basin and Index of Reproductive Activity values were used as criteria to identify the species that perform long-distance longitudinal migrations for reproduction. The study confirmed the classification of long-distance longitudinal migration species; however, some species were not classified as described in the literature. The proposed sequential criteria have proven to be effective in the classification of long-distance longitudinal migrations species and certainly contribute to filling some existing knowledge gaps of reproductive traits. This classification is of fundamental importance in planning new dam projects, in decision making, and the development of management and conservation actions for the ichthyofauna. This article is protected by copyright. All rights reserved.

中文翻译：

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新热带鱼类繁殖活动的空间隔离作为洄游性状的指标

本研究以巴西库亚巴河 430 公里长的河段为模型，重点研究具有高繁殖活性的鱼类沿流域的分布情况。主要目标是在所有流域物种中确定那些为了繁殖而长距离洄游的鱼类。因此，提出了一套工作标准，根据物种的繁殖行为（即繁殖活动和分布）对物种进行分类。从 2000 年到 2004 年，在库亚巴河流域进行了采样，包括繁殖期（10 月至 2 月之间）的几种环境（河流、渠道和湖泊）。整个盆地的物种出现（存在和不存在 - 分布代理）和繁殖活动指数值被用作标准来识别执行长距离纵向迁移繁殖的物种。研究证实了长距离纵向迁徙物种的分类；然而，有些物种没有按照文献中的描述进行分类。提议的顺序标准已被证明在长距离纵向迁移物种的分类中是有效的，并且肯定有助于填补一些现有的生殖性状知识空白。这种分类对于新水坝项目的规划、决策以及鱼群管理和保护行动的发展至关重要。本文受版权保护。