Many marine animals are difficult to study because they are widely dispersed across oceans and are not captured by traditional sampling methodologies such as fishery surveys. A case in point is the Portuguese man of war (Physalia physalis) (Linnæus, 1758), which despite being pleustonic and remarkably conspicuous, is one of the least studied and understood gelatinous zooplankton species, especially in terms of its ecology. During August to October 2016, the Irish coastline experienced the largest mass stranding of P. physalis in over 150 years. At the same time, P. physalis were recorded offshore in the Porcupine Seabight. Here we used these stranded and offshore observations of P. physalis to inform a Lagrangian particle-tracking model forced by wind to 1) hindcast the backwards drift of this species for three months to determine their likely origin and provide some insights on likely pathways to Irish shores and, 2) forecast the drift of this species towards the Irish coastline. Hindcasting stranded P. physalis from the Irish coastline suggested that they most likely originated from an extensive source area located over the European basin but ultimately from the North Atlantic Current. Our forecast model indicated that particles released from the Porcupine Seabight stranded on Irish shores, in fact, stranding patterns were 82% similar to actual strandings. Both models combined suggested that the Porcupine Seabight was an important source area, but that many P. physalis likely originated from further south and took a more tortuous trajectory towards Ireland determined by wind. This study also highlights the value of collecting routine beach strandings data and opportunistic offshore visual observations to inform future coastal and shelf modelling studies.

许多海洋动物难以研究，因为它们广泛散布在海洋中，并且未被传统的抽样方法（如渔业调查）捕获。一个典型的例子是葡萄牙军人（Physalia physalis）（Linnæus，1758年），尽管是浮游动物且非常引人注目，但它是最少研究和了解的胶状浮游动物之一，尤其是在生态学方面。在2016年8月至2016年10月期间，爱尔兰海岸线经历了150年来最大的酸浆假单胞菌搁浅。与此同时，P.酸浆是在豪猪Seabight离岸记录。在这里，我们使用了对空泡的这些滞留和近海观测告知受风强迫的拉格朗日粒子追踪模型：1）对该物种的向后漂移进行了三个月的后向预测，以确定它们的可能起源，并对通往爱尔兰海岸的可能途径提供了一些见解，以及2）预测了该物种向爱尔兰的海岸线。后报搁浅P.酸浆从建议的，他们最有可能是源于位于在欧洲盆地，但最终从北大西洋暖流的来源广泛区域爱尔兰海岸线。我们的预测模型表明，豪猪海域释放的颗粒滞留在爱尔兰海岸，实际上，滞留模式与实际滞留相似为82％。两种模型的结合都表明，豪猪海域是一个重要的来源地区，但是许多P. physalis可能起源于更南部，并由风决定走向爱尔兰的曲折轨迹。这项研究还强调了收集常规海滩搁浅数据和机会主义海上目视观察的价值，以为将来的海岸和陆架建模研究提供参考。