KARACHI: The recent greenish discolouration of seawater and reports of glowing waves along Karachi and parts of the Balochistan coast are the result of a naturally occurring, non-toxic bloom of Noctiluca scintillans — commonly known as “sea sparkle” — and not caused by pollution, the World Wide Fund for Nature–Pakistan (WWF-P) clarified on Wednesday.
Dismissing concerns about harmful algal blooms or eutrophication, WWF-P explained that the phenomenon is linked to the seasonal proliferation of Noctiluca scintillans, a free-floating marine organism known for its striking bioluminescence at night.
According to the organisation, the greenish hue is produced by the organism’s internal symbiont, Protoeuglena noctilucae, which supports rapid growth through photosynthesis. While the organism can appear red, orange, green or colourless, blooms along Pakistan’s coast are most commonly green or orange and may spread widely depending on seasonal conditions.
WWF-P noted that similar natural blooms have been recorded across regional coastlines, including Yemen, Oman, Iran, Pakistan, and western India.
