Coastal Waters in Karachi and Balochistan Turn Green

The coastlines of Karachi and Balochistan have recently displayed an unusual greenish tint in their waters, along with a glowing effect at night—an unexpected change that initially alarmed fishermen and local residents who feared the discoloration signaled toxic pollution or a hazardous algal bloom.

However, environmental experts have now clarified the nature of the phenomenon. According to WWF-Pakistan, the striking color and nighttime glow are caused by a microscopic marine organism known as Noctiluca scintillans, commonly referred to as “sea sparkle.” The organization explained that this organism naturally occurs in coastal waters and can emit green, red, orange, or even colorless shades. Along Pakistan’s shoreline, green and orange hues are most commonly observed.

WWF-Pakistan stressed that the “sea sparkle” occurrence is seasonal, harmless, and not linked to toxic pollution, reassuring communities who were concerned about potential risks to health or marine life.

Despite this clarification, the WWF cautioned that Karachi continues to face a serious and unrelated environmental crisis. The city’s coastal ecosystem remains under heavy threat due to unchecked pollution. Large volumes of industrial and domestic waste, untreated sewage, solid debris, and oil contaminants flow into the Arabian Sea every day through the Lyari and Malir rivers. This ongoing pollution, the organization warned, poses a far greater threat to marine biodiversity and the livelihoods of coastal communities than the naturally occurring sea sparkle.

Authorities and environmental groups continue to urge immediate action to address Karachi’s persistent coastal pollution problem while assuring the public that the current green coloration of the waters is not a sign of toxicity.