<span style="font-size:11.0pt;font-family: "Times New Roman","serif";mso-fareast-font-family:"Times New Roman";mso-bidi-font-family: Mangal;mso-ansi-language:EN-GB;mso-fareast-language:EN-US;mso-bidi-language: HI" lang="EN-GB">Occurrence of red tide caused by <i>Karenia</i><i style="mso-bidi-font-style: normal"> mikimotoi</i> (toxic dinoflagellate) in the Southwest coast of India</span>

Abstract

<span style="font-size:11.0pt;font-family: " times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";mso-bidi-font-family:="" mangal;mso-ansi-language:en-gb;mso-fareast-language:en-us;mso-bidi-language:="" hi"="" lang="EN-GB">Intense brownish discoloration was observed in the surface waters of Cochin barmouth on 21^st October 2009, which found to extend a few kilometers in the coastal waters. Continuous monitoring was carried out in the region for a period of 5 days (21^st to 25^th October 2009) and generated data on changes in water quality and phytoplankton community associated with the bloom. Relatively high level of inorganic nutrients (ammonia 0.5-9.7 µM, nitrate 1.3-2.9 µM, phosphate 1-2.3 µM, silicate 23.5-39.9 µM) and chlorophyll <i>a</i> (av. 56.8 ± 23.7 mg m^-3) concentration were observed during the bloom period. Microscopic analysis revealed that the discoloration was caused by an unarmored toxic dinoflagellate, <i>Karenia mikimotoi</i> Miyake &amp; Kominami ex Oda (<i>Karenia</i>, Gymnodiniaceae) belongs to Gymnodiniales, which <span style="font-size:11.0pt;font-family:" times="" new="" roman","serif";mso-fareast-font-family:="" "times="" roman";mso-bidi-font-family:mangal;mso-ansi-language:en-gb;="" mso-fareast-language:en-us;mso-bidi-language:ml"="" lang="EN-GB">cause massive fish mortality by releasing hemolytic compounds<span style="font-size:11.0pt; font-family:" times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";="" mso-bidi-font-family:mangal;mso-ansi-language:en-gb;mso-fareast-language:en-us;="" mso-bidi-language:hi"="" lang="EN-GB">.<span style="font-size:11.0pt; font-family:" times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";="" mso-bidi-font-family:mangal;mso-ansi-language:en-gb;mso-fareast-language:en-us;="" mso-bidi-language:ml"="" lang="EN-GB"> </span></span></span></span>