The Benguela Upwelling System (BUS) is subject to a high incidence of HABs. Of the major shellfish poisoning syndromes associated with HABs, Paralytic and Diarrhetic Shellfish Poisoning (PSP and DSP) pose the greatest concern, but as documented herein there are several other HAB organisms that are also present. Blooms of Alexandrium catenella have been recognised as the typical cause of PSP since 1948. In addition to the risk posed to human health A. catenella has also been the cause of large shellfish and bird mortalities. An additional risk of PSP is provided by Alexandrium minutum first detected in Cape Town harbour in 2003. DSP was identified on the South African coast for the first time in 1991. Although several Dinophysis spp. known to cause DSP have been recognized as a component of the plankton of the region, it is accepted that DSP is usually attributed to D. acuminata or D. fortii. In the southern Benguela both Pseudo-nitzschia australis and Pseudo-nitzschia multiseries have been identified and shown to produce domoic acid. Multiple Pseudo-nitzschia spp. have been identified in the northern Benguela with the potentially toxigenic Pseudo-nitzschia pungens and P. australis dominant inshore. The yessotoxin (YTX) producing dinoflagellates Gonyaulax spinifera, Lingulodinium polyedrum and Protoceratium reticulatum are all known to form blooms and YTXs have been the cause of massive mortalities of farmed abalone. Prominent fish-killing blooms include Karlodinium veneficum in the northern Benguela and Karenia cristata in the southern Benguela. Shellfish farms in an embayment of the southern Benguela have suffered reduced growth rates due to the ecosystem disruptive blooms of Aureococcus anophagefferens. High biomass dinoflagellate blooms often attributed to Tripos and Prorocentrum spp. characterise the entire region and major mortalities of marine life are regularly attributed to their decay and the subsequent development of anoxic conditions.

Benguela上升流系统（BUS）容易发生HAB。在与HAB相关的主要贝类中毒综合症中，麻痹性和腹泻性贝类中毒（PSP和DSP）引起了最大的关注，但是如本文所述，还有其他几种HAB生物也存在。自1948年以来，亚历山大连叶藻的大量繁殖已被认为是PSP的典型病因。除了对人体健康的危害外，卡连氏杆菌也已成为造成大量贝类和鸟类死亡的原因。PSP的另外一个风险是由提供亚历山大藻在开普敦港2003年第一DSP检测被确定在南非海岸，第一次在1991年虽然有几个鳍藻spp。已知引起DSP的生物已经被认为是该地区浮游生物的组成部分，人们普遍认为DSP通常归因于D. acuminata或D. fortii。在南部格拉两者拟菱形藻芦苇和拟菱形藻multiseries已经确定，并示出以产生软骨藻酸。多假性尼兹菌属。已经在本格拉北部已确定与潜在产毒尖刺拟菱形藻和芦苇主导近海。产生毒素的Yysotoxin（YTX）棘孢菌，多叶灵芝和网状原角藻众所周知，它们会形成花朵，YTX导致养殖鲍鱼大量死亡。引人注目的杀鱼花开包括本格拉北部的Karlenodinium v​​eneficum和本格拉南部的Karenia cristata。在本格拉南部南部的一个贝类养殖场，由于嗜虾金黄色葡萄球菌的生态系统破坏性繁殖，其增长率下降。高生物量的鞭毛藻绽放通常归因于Tripos和Prorocentrum spp。表征整个区域，海洋生物的主要死亡通常归因于其腐烂和缺氧条件的随后发展。