In 2018, the presence of bottom water hypoxia along the SW Florida coast was investigated during a bloom of the toxic dinoflagellate Karenia brevis. The bloom was first detected in November 2017. Monitoring of oxygen levels and bloom densities was carried out in 2018 and 2019 using sampling grids. Vertical profiles indicated a pycnocline at 3–4 m where warmer, lower salinity water was at the surface, while the deeper hypoxic layer was colder with higher salinity. There were significantly higher abundances of K. brevis in the surface water compared to the hypoxic bottom water in September 2018. At two fixed sites, dissolved oxygen was measured continuously showing hypoxic conditions during that month. Geospatial analysis of vertical profile data yielded an estimate that the hypoxic layer covered an area of at least 655 km². The possible influences of red tides on hypoxic conditions along the coast of the eastern Gulf of Mexico are discussed within the context of the 2018 K. brevis bloom event. Hypoxia occurring in parallel to a red tide bloom is more likely to occur with warmer ocean temperatures and increased fluxes of nutrients and fresh water to the Gulf of Mexico after hurricanes.

2018 年，在有毒鞭毛藻Karenia brevis 大量繁殖期间，调查了佛罗里达州西南部海岸底水缺氧的存在。藻华于 2017 年 11 月首次被检测到。 2018 年和 2019 年使用采样网格对氧气含量和藻华密度进行了监测。垂直剖面表明，在 3-4 m 处有一个pycnocline，其中较温暖、盐度较低的水位于地表，而较深的缺氧层较冷，盐度较高。K. brevis 的丰度显着更高与 2018 年 9 月的低氧底水相比，地表水中的溶解氧。在两个固定地点，连续测量溶解氧，显示该月处于低氧状态。对垂直剖面数据的地理空间分析得出的估计值是，缺氧层覆盖的面积至少为 655 km ²。赤潮对墨西哥湾东部沿岸缺氧条件的可能影响将在 2018 年短赤藻爆发事件的背景下进行讨论。与赤潮水华同时发生的缺氧更有可能发生在海洋温度升高以及飓风过后进入墨西哥湾的营养物质和淡水通量增加的情况下。