Zooplankton phototaxis in oceanic squid fishing grounds in the Arabian Sea

Abstract

1528-1532<span style="font-size:9.0pt;mso-bidi-font-size: 11.0pt;font-family:" times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";="" color:black;mso-ansi-language:en-gb;mso-fareast-language:en-us;mso-bidi-language:="" hi"="" lang="EN-GB">Effects of night-illumination on zooplankton abundance were compared with day/night variations in oceanic squid fishing grounds in central Arabian Sea. Zooplankton abundance sh<span style="font-size:9.0pt; mso-bidi-font-size:11.0pt;font-family:" times="" new="" roman","serif";mso-fareast-font-family:="" "times="" roman";color:black;mso-ansi-language:en-gb;mso-fareast-language:="" en-us;mso-bidi-language:ml"="" lang="EN-GB">owed significant variation in relation to three different light conditions with 52% of the total abundance happening during night and 25% during night with illumination. Siphonophores, chaetognaths, copepods and decapod larvae displayed negative phototaxis. Present results indicate that the <span style="font-size:9.0pt;mso-bidi-font-size:11.0pt; font-family:" times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";="" color:black;mso-ansi-language:en-gb;mso-fareast-language:en-us;mso-bidi-language:="" ml"="" lang="EN-GB">response to light stimulus observed among the zooplankton groups were mostly due to the prey-seeking or predator avoidance behavior.</span