Daily Decay (31st January 2017): Unidentified Cockle (F. Cardiidae) @ Changi

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Photo: Francis Canlas

Philippines: Massive fish kill hits Lake Sebu anew; state of calamity mulled
31st January 2017;

The Municipal Government of Lake Sebu in South Cotabato is planning to declare the area under the state of calamity due to another major fish kill that already destroyed around P6.5-million worth of Tilapia (Oreochromis niloticus).

Zaldy Artacho, Lake Sebu municipal agriculture officer, said Tuesday, January 31, that the ongoing fish kill started late last week in portions of the lake after its dissolved oxygen dropped to critical levels anew.

He said the phenomenon, known locally as “kamahong,” came after almost a week of sporadic heavy rains in the area.

Artacho said several fish cage operators initially reported on Friday afternoon that some of their Tilapia appeared gasping for air.

“By night time, the fish kills already started in a number of fish cages,” he said in a radio interview.

Citing their initial assessment, Artacho said a total of 72,335 kilos of Tilapia have been destroyed as a result of the incident.

The prevailing farm gate price for Tilapia in Lake Sebu is P90 per kilo.

Artacho said this figure only came from 19 affected fish cage operators in Barangays Poblacion and Takonel.

He said the validation and assessment is ongoing for the other affected fish cage operators. It was earlier estimated at more than 300.

Some operators were forced to conduct massive emergency harvests over the weekend in a bid to save the remaining Tilapia, he added.

As a result of the incident, Artacho said Mayor Antonio Fungan ordered their office and the barangays affected to prepare the necessary data for the declaration of a state of calamity.

The affected barangays were also ordered to to fast-track their calamity declarations.

Fishery officials had blamed the fish kills to the occurrence of “kamahong,” a phenomenon caused by the sudden rise in the water’s temperature.

Kamahong,” which usually occurs during the rainy season, triggers the rise of sulfuric acid in the lake’s waters, eventually causing a massive fish kill.

The Office of the Provincial Agriculturist said the phenomenon occurs when cold rainwater, which is heavier than warm water, settles at the abyssal zone of the lake.

It causes the upturn or upwelling of warm water carrying silts, sediments and gases such as hydrogen sulfide, ammonia, sulphur and methane gas produced by the decomposing organic matter such as fish feeds.

Such situation results in the reduction of dissolved oxygen in the water, “forcing fishes to take in oxygen directly from the atmosphere and eventually die,” it said.

Last year, the Municipal Government of Lake Sebu recorded at least eight fish kills that destroyed around P1.4-million worth of Tilapia. The last major fish kill in the area was in 2014.

Source: Sun.Star

More than 300 fish cage operators were affected by the fish kill in Lake Sebu in South Cotabato which started since Friday.
Photo: Francis Canlas

Philippines:5 tons of Tilapia die in South Cotabato fish kill
By Francis Canlas, 31st January 2017;

Five tons of Tilapia (Oreochromis niloticus) with an estimated worth of P4.5 million were found dead and floating in Lake Sebu in South Cotabato since Friday.

According to local authorities, more than 300 fish cage operators were affected by the fish kill. The number is expected to rise when an assessment is conducted on Tuesday.

At least 90% of the fish cages were affected by the fish kill.

Jonathan Tomayao, one of the affected operators, lost P225,000 worth of Tilapia fingerlings. He believes non-stop rains last week triggered the fish kill.

Dahan-dahan, kaya ito ang epekto n’ya mas malakas ang epekto. Mas mabuti payung biglaan pagkalipas ng ilang araw, makarekober na sila. Pero kapag ganito ang panahon na dahan-dahan mas malaki ang epekto nito,” he said.

(The rain was gradually pouring, and it has this effect. It’s better to have heavy rains in one go. After a few days, the fingerlings would recover. When the rain is gradual and continuous, it has worse effects on the fingerlings.)

Some operators were forced to harvest and sell their Tilapia to buyers.

Dalawang daliri lang kalaki ipalabas na, baka sakaling mabenta pa, ang iba hindi naman nabenta,” said operator Nilda Prado.

(We harvested fish the size of two fingers in hope of having them sold in the market. Most were not bought.)

The town’s agriculturist, Zaldy Artacho, explained that lack of oxygen caused the fish kill.

Source: ABS-CBN News

Button Snails (Umbonium vestiarium)
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