Kota Kinabalu: The discovery of dead fish in the Papar River at Kg Kuala, Papar since Monday (Feb 15) is most likely due to poisoning, said incoming Sabah Fishery Department Director Dr Ahemad Sade .
Nonetheless, he said the department would disclose the actual cause as soon as results of post mortem and analysis of samples taken from the affected river are completed. The results could be made known within a month.
"Looking at the overall situation in regard to the dead fishes, they were of different sizes as well as the prawns mentioned in the discovery.
"I believe poisoning is the most probable cause in this incident because poison would just kill the marine species regardless of their size.
According to Dr Ahemad, the department received a report of a similar incident that happened at the Papar River near the fish market at the township at about 10am on Feb. 8.
He said samples of the fishes and water from the river at the affected area have been collected and sent to the Likas Fishery Research Centre to be analysed.
He said this to Daily Express when contacted, Thursday. On whether red tide could be another possible factor, he said the occasional natural phenomenon in the state may not be possible as population of plankton algae (dinoflagellates- cochlodinium polykrikoides populations) at Papar is not high based on the department's monitoring system.
This plankton caused another type of red tide when it undergoes population explosion and would deplete oxygen in the sea water that kills fish via suffocation.
"If this plankton was found growing in large numbers, then it would be very harmful to the fish but as of now, its number has not reached worrying level in Papar.
"Another reason is because I see the affected river in Kg Kuala has brackish water that would not be a preferred habitat for these dinoflagellates- cochlodinium polykrikoides as they can be found naturally living in sea water."
Whenever there is such an incident, Dr Ahemad said a task force comprising Sabah Fishery Department, Department of Environment (DOE) and Health Department would direct its respective officers to the exact location to collect samples from the affected river.
"Our officers from the department's Fishery Research Centre in Likas have been directed to collect some fish samples while the DOE will take water samples from the river.
In the meantime, Dr Ahemad concurred with Pantai Manis Assemblyman Datuk Seri Abdul Rahim Ismail that Papar folks should not consume freshwater fish and few types of saltwater fish.
Among the types are mullet fish, silver catfish, catfish, red snapper and sea bass.
DOE Sabah Director Datin Hanili binti Ghazali told Daily Express that the jurisdiction of the department was solely on the water quality at the affected river at Kg Kuala Papar.
"If analysis results of the samples show content of chemical pollutant from an industry, we can take action based on our provisions and Act where an industry found exceeding the standard that has been set, will face the law.
For example, Hanili said scores of fish found floating on the surface of a monsoon drain filled with water in Kolombong, last year, was actually caused by red tide and the fishes were already dead at sea.
She said the dead fishes actually flowed from the sea into a certain river, during high tide, that later ended up on the surface of the monsoon drain.
"If the actual cause of the dead fishes occurred because of natural phenomenon, then it would be a different matter," she said.