DAMA: the global Distribution of Alien Mammals database

We developed the DAMA (Distribution of Alien MAmmals) database, a comprehensive source reporting the global distribution of the 230 species of mammals that have established, self-sustaining and free-ranging populations outside their native range due to direct or indirect human action. Every alien range is accompanied by information on its invasion stage, pathway, method of introduction and date of introduction. We collected information from 827 different sources (scientific literature, books, risk assessments, reports, online biodiversity databases and websites), and used it to draw alien range maps for these species following the IUCN mapping framework. DAMA comprises 2726 range polygons, covering 199 Countries, 2190 level 1 administrative areas and 11 zoogeographic realms for the period 21500 BC-AD 2017. The most represented orders among introduced mammal species are Rodentia (n=58, 25.22%), Cetartiodactyla (n=49 species, 21.30%), Carnivora (n=30 species, 13.04%), Diprotodontia (n=28, 12.17%) and Primates (n=26, 11.30%). Mammal species have been frequently introduced for hunting (n=100), pet trade (n=57), conservation (n=51) and fauna improvement (n=42). The majority of range polygons are placed on islands (n=2196, 80.56%), encompass populations that have moved beyond establishment and into the invasion stage (n=1655, 60.71%), and originated from 1500 AD to the present (n=1496, 54.88%). Despite inheriting literature biases towards more studied regions (e.g., developed Countries), DAMA is the most up-to-date picture of alien mammal global distribution and can be used to investigate their invasion ecology across different biogeographical regions.我们研发了DAMA（Distribution of Alien MAmmals）数据库，该数据库是一套全面的数据源，收录了230种因人类直接或间接活动而在原生分布区外建立可自主存续且自由扩散种群的哺乳动物的全球分布信息。每一个外来分布范围均附带其入侵阶段、入侵路径、引入方式与引入日期等相关信息。研究团队从827个不同来源（包括科学文献、专著、风险评估报告、各类报告、在线生物多样性数据库及相关网站）采集数据，并依据世界自然保护联盟（International Union for Conservation of Nature，IUCN）的制图框架，为上述物种绘制了外来分布范围地图。DAMA数据库共计包含2726个分布范围多边形，覆盖公元前21500年至公元2017年期间的199个国家、2190个一级行政区以及11个动物地理区。在外来哺乳动物物种中，占比最高的五个类群依次为啮齿目（Rodentia，共58种，占比25.22%）、鲸偶蹄目（Cetartiodactyla，共49种，占比21.30%）、食肉目（Carnivora，共30种，占比13.04%）、双门齿目（Diprotodontia，共28种，占比12.17%）以及灵长目（Primates，共26种，占比11.30%）。哺乳动物的引入用途主要涵盖狩猎（共100种）、宠物贸易（共57种）、物种保护（共51种）以及野生动物区系改良（共42种）。绝大多数分布范围多边形位于岛屿区域（共2196个，占比80.56%），覆盖的种群已完成建立并进入入侵阶段（共1655个，占比60.71%），且其引入时间集中于公元1500年至今（共1496个，占比54.88%）。尽管该数据库继承了现有文献对研究程度较高区域（如发达国家）的采样偏倚，但DAMA仍是当前最贴合全球外来哺乳动物分布现状的数据集，可用于探究不同生物地理区域内的外来哺乳动物入侵生态学问题。