Incidents of bathers being stung by jellyfish on the coast of southern Brazil have been monitored from 2012 to 2022 to identify the species involved and to search for patterns of behavior in different summer seasons. For 10 years of monitoring, data on occurrence, density and the crossing with the abiotic variables of temperature and salinity of the water and wind direction were obtained. During the investigated period, seven species of macro jellyfish were recorded out, four of them were urticating species, in wich Olindias sambaquiensis was the most frequent and abundant. Based on physical-chemical data on the seawater in this area, the cohorts, and consequently the success in the recruitment and the density of the O. sambaquiensis, may be related with years of low salinity of these Coastal Water. This hydrozoan was also the only species that showed a correlation between average annual density values and incidents of bathers being stung in subsequent summers. Likewise, on a monthly time scale, incidents of stings were correlated with winds from the south quadrant that could promote the transport of organisms to the beach region. A predictive model of the occurrence of jellyfish stinging events is presented and applied for the summer of 2023.

2012年至2022年期间，我们对巴西南部海岸的沐浴者被水母蜇伤的事件进行了监测，以识别相关物种并寻找不同夏季的行为模式。经过10年的监测，获得了发生率、密度以及与水温、盐度和风向等非生物变量的交叉数据。调查期间共记录到7种大型水母，其中4种为荨麻水母，其中以Olindias sambaquiensis最为常见、数量最多。根据该地区海水的物理化学数据、种群以及桑巴奎O. sambaquiensis的成功招募和密度，可能与这些沿海水域多年的低盐度有关。这种水螅动物也是唯一一种显示出年平均密度值与随后夏季沐浴者被蜇事件之间存在相关性的物种。同样，在每月的时间尺度上，蜇伤事件与来自南象限的风相关，风可以促进生物体向海滩地区的运输。提出并应用了 2023 年夏季水母蜇伤事件发生的预测模型。