Abstract Invasion pathways and invasion-related lags are critical to understand the invasion process and to manage invasive species. The challenge of dealing with introduced populations increases when charismatic species are involved, such as the case of invasive squirrels. In this study, we integrate previous information into a comprehensive description of the invasion process of Callosciurus erythraeus in Argentina, and we synthesise a framework of invasion pathways and associated lag times for introduced squirrel species. One of the main invasion pathways for introduced squirrels involves the trade of pets and ornamental wildlife, i.e. deliberate transportation by humans as vectors using routes of pet/ornamental trade. This was the case of the importation of C. erythraeus into Argentina in 1970 that originated an invasion focus, which firstly spread through squirrels dispersing into nearby habitat (unaided spread). Apart from this local spread, we have recorded a total of 31 translocations within the country of squirrels taken 33−933 km from the source site (aided spread). Most of these translocations-releases occurred close to the invasion foci that functioned as a source of squirrels. Therefore, a key pathway for the invasion of C. erythraeus in Argentina is the illegal and intentional transport of individuals within country boundaries. Time lags can be found throughout the invasion process. We have previously described a lag in population growth and range expansion in the main invasion focus, and also a lag in vector activity (i.e. a lag in the onset of translocations). We now report a lag in the time between the detection by residents of C. erythraeus in a new area and when they report its observation. This time lag shows a decreasing trend, i.e. recent releases are reported sooner, that could respond to a changing lag in the perception of the problem due to communication activities. We propose a general conceptual framework for invasive squirrels that integrates two invasion pathways (A: aided spread that determines the number of invasion foci, and B: unaided spread that determines the size of each invasion focus) and three types of time lags (1: lag in population growth and spread, 2: lag in vector activity, and 3: lag in perception of the problem (human dimension)). Communication and education activities can be a powerful tool to change perceptions and gain support and active engagement of the local community to deal with invasive, charismatic species. Long-term communication programmes should be implemented along with strict and coordinated government policies.

中文翻译：

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引入阿根廷的 Callosciurus erythraeus 传播的入侵途径和滞后时间

摘要 入侵途径和入侵相关滞后对于了解入侵过程和管理入侵物种至关重要。当涉及有魅力的物种时，处理引入种群的挑战就会增加，例如入侵松鼠的情况。在这项研究中，我们将先前的信息整合到对阿根廷 Callosciurus erythraeus 入侵过程的全面描述中，并综合了入侵途径框架和引入的松鼠物种的相关滞后时间。引入松鼠的主要入侵途径之一涉及宠物和观赏野生动物的贸易，即人类作为载体使用宠物/观赏贸易路线故意运输。这就是 1970 年将 C. erythraeus 输入阿根廷的情况，它引发了入侵焦点，首先通过松鼠散布到附近的栖息地（无助传播）。除了这种局部传播之外，我们还记录了在距源地点 33-933 公里（辅助传播）的松鼠国家内共发生了 31 次易位。大多数这些易位释放发生在作为松鼠来源的入侵灶附近。因此，C. erythraeus 在阿根廷入侵的一个关键途径是在国家边界内非法和故意运输个人。在整个入侵过程中可以发现时间滞后。我们之前已经描述了主要入侵焦点的种群增长和范围扩展的滞后，以及媒介活动的滞后（即易位开始的滞后）。我们现在报告 C 居民发现之间的时间滞后。erythraeus 在一个新的区域，当他们报告它的观察时。该时间滞后显示出减少的趋势，即较早地报告最近的发布，这可以响应由于通信活动而导致的对问题感知的变化滞后。我们为侵入性松鼠提出了一个总体概念框架，该框架整合了两种入侵途径（A：确定入侵灶数量的辅助传播，B：确定每个入侵焦点大小的独立传播）和三种类型的时间滞后（1：人口增长和传播滞后，2：媒介活动滞后，3：对问题的认知滞后（人的维度））。交流和教育活动可以成为改变观念并获得当地社区支持和积极参与以应对入侵的、有魅力的物种的有力工具。