From the 1950s onwards, programmes to promote aquaculture and improve capture fisheries in East Africa have relied heavily on the promise held by introduced species. In Tanzania these introductions have been poorly documented. Here we report the findings of surveys of inland water bodies across Tanzania between 2011 and 2017 that clarify distributions of tilapiine cichlids of the genus Oreochromis. We identified Oreochromis from 123 sampling locations, including 14 taxa restricted to their native range and three species that have established populations beyond their native range. Of these three species, the only exotic species found was blue-spotted tilapia (Oreochromis leucostictus), while Nile tilapia (Oreochromis niloticus) and Singida tilapia (Oreochromis esculentus), which are both naturally found within the country of Tanzania, have been translocated beyond their native range. Using our records, we developed models of suitable habitat for the introduced species based on recent (1960–1990) and projected (2050, 2070) East African climate. These models indicated that presence of suitable habitat for these introduced species will persist and potentially expand across the region. The clarification of distributions provided here can help inform the monitoring and management of biodiversity, and inform policy related to the future role of introduced species in fisheries and aquaculture.

中文翻译：

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引进的 Oreochromis 罗非鱼对坦桑尼亚集水区的广泛殖民：数十年故意引进的遗产

从 1950 年代起，促进东非水产养殖和改善捕捞渔业的计划在很大程度上依赖于引进物种的承诺。在坦桑尼亚，这些介绍的记录很少。在这里，我们报告了 2011 年至 2017 年间坦桑尼亚内陆水体调查的结果，这些调查结果阐明了 Oreochromis 属罗非鱼慈鲷的分布。我们从 123 个采样地点确定了 Oreochromis，包括 14 个仅限于其原生范围的分类群和 3 个在其原生范围之外建立种群的物种。在这三个物种中，唯一发现的外来物种是蓝点罗非鱼 (Oreochromis leucostictus)，而尼罗罗非鱼 (Oreochromis niloticus) 和辛达罗非鱼 (Oreochromis esculentus) 均在坦桑尼亚境内自然发现，已经转移到他们的原生范围之外。使用我们的记录，我们根据最近（1960-1990 年）和预计（2050 年、2070 年）东非气候为引入的物种开发了合适​​的栖息地模型。这些模型表明，这些引入物种的合适栖息地将持续存在，并可能在整个地区扩大。此处提供的分布说明有助于为生物多样性的监测和管理提供信息，并为与引进物种在渔业和水产养殖中的未来作用相关的政策提供信息。这些模型表明，这些引入物种的合适栖息地将持续存在，并可能在整个地区扩大。此处提供的分布说明有助于为生物多样性的监测和管理提供信息，并为与引进物种在渔业和水产养殖中的未来作用相关的政策提供信息。这些模型表明，这些引入物种的合适栖息地将持续存在，并可能在整个地区扩大。此处提供的分布说明有助于为生物多样性的监测和管理提供信息，并为与引进物种在渔业和水产养殖中的未来作用相关的政策提供信息。