Recently a strange phenomenon occurred at Gadani Jetty area that once used to be a beautiful blue water lagoon, turned into a pink-foul-smelly wetland. NIMA’s marine scientists unearthed the truth behind this mystery.
Upon hearing the media reports, President NIMA directed the NIMA scientists’ at Karachi Chapter to conduct an onsite investigation and collect samples for laboratory tests to further substantiate the facts. This being a very rare occurrence, drew extraordinary attention of marine environmental experts and local public. It also sparked an online debate. NIMA SMEs responding to the exigency, reached the affected area and conducted their onsite inspection procedures. Sea water in and around the jetty area was physically examined for its odor and distinctive characteristics. Moreover, samples from the affected areas were also preserved for physio-chemical parameters’ examination at the laboratory. In some areas dead fish were also observed.
In the marine scientific community, such ‘pink tide’ is characterized by its distinctive discoloration of seawater, caused by blooms of color-producing microorganisms such as salt-loving bacteria or sea plants commonly known as Halophilic Organisms or Algae. These microbes release natural pigments of various shades i.e. pink, red, green or yellow, depending on environmental conditions and presence of specific algal or microbial species. It is noteworthy that such ‘pink tides’ have been appearing in different parts of the world i.e. Australia, United States, Mediterranean, and Southeast Asia. In South Asian region, similar happenings had been reported along the Indian, Sri Lankan and Pakistani coastlines. In Pakistan, this ‘pink tide’ at Gadani marks the 3rd documented incident; near Karachi in 2017 and along the Makran coast in 2021.
The lab tests of samples collected by NIMA SMEs, revealed several environmental stressors that exacerbated this unusual bloom. The seawater temperature measured near the jetty area was 36.5°C, considerably higher than average sea water (< 24.5 – 29.50C> in coastal zones). Localized heating of this water body caused burgeoning of algal and bacterial growth. Salinity was observed close to 48 Parts Part Thousands (PPT), a significant increase over typical oceanic levels of 35 PPT. Whereas, turbidity level (suspended particles present in water) reached 47 Nephelometric Turbidity Unit (NTU), as compared to the normal range of 1 – 5 NTU. Nutrient analysis detected Ammonium at 2.256 mg/L (normal range 0.0018 – 0.036 mg/L) and Phosphate at 5.739 mg/L (normal range 0.0095 – 0.285 mg/L); both readings observed much above the normal concentrations; a nutrient enriched environment supported bacterial and algal growth. The pH value indicated 6.94 (normal range 7.5 – 8.3), indicating slightly acidic behavior. Moreover, TDS of the water measured at 47,886 mg/L as equated to the usual range of 30,000 – 40,000 mg/L. Conductivity level of the affected water was gauged around 96,032 mg/L as compared to normal range of 22,750 mg/L.
In this backdrop, NIMA’s scientists concluded that a combination of factors, like highly nutrient enriched environment due to lack of sea water circulation pattern (caused by faulty jetty’s design) contributed towards unusual rise in salinity and temperature inside this lagoon. It provided optimal conditions for color-producing bacteria and algae to flourish in Gadani jetty waters. It is important to note that these specific conditions do not typically happen in open waters due to natural dilution of all above cited parameters.
Highlighting the impacts of ‘pink tide’ on humans, the NIMA team emphasized that it is utterly important that whenever such Harmful Algal Bloom (HAB) is observed in or around the costal zones, a direct contact with the affected water is to be avoided i.e., swimming, wading, or engaging in water associated activities. These blooms can cause health issues like skin irritation. Some HABs produce toxins that can contaminate marine organisms and prove harmful if consumed as dead fish has been reported around these areas as well. It is, therefore, highly recommended not to consume sea food caught from these affected waters until authorities have confirmed it to be safe for human consumption.
Based on these conclusive evidence, NIMA’s team strongly suggested that Balochistan Environmental Protection Agency (BEPA) stipulated safety protocols be immediately complied with to ensure safety of related coastal communities and visitors. In addition, the concerned authorities are to initiate design modifications around the jetty area to improve water flow circulation pattern. President NIMA Vice Admiral Ahmed Saeed HI(M) (Retd) urged that safety of the coastal communities and conservation of our vital marine ecosystem must take precedence at provincial and national levels.
