Fish need shade, too, from sun
By Yolanda Sotelo
LINGAYEN -Even the fish cultured in ponds need a shade from the punishing heat of the sun.
Some fishpond operators are growing kangkong (water spinach), a semi-aquatic plant which crawl above the water and which serve as “shade” for the fish when the sunlight is intense.
Jayson Zulueta, a project staff of the Bureau of Fisheries and Aquatic Resources (BFAR) on climate-resilient aquaculture operations, said it was the pond operators in Isabela and Pampanga who practice “shading” of ponds using kangkong.
Some operators used to remove the kangkong, an edible plant, from their ponds, saying these hinder efficient harvesting of fish.
“Now, they allow the kangkong to grow as they observed that the fish go under the plant when it is very hot. This is their adoptive strategy,” he said.
A bonus is that they would have some vegetables to go with their fish broth.
Zulueta said the BFAR central office conducted workhops on the project which he presented during the fishery industry forum of BFAR Ilocos Region in Lingayen on Friday.
The workshops were on seaweeds, closed water and open water systems. It would also hold a workshop of lakes and water reservoir.
He said the objectives include the interaction of aquafarmers to know their observations on impact of weather systems like habagat, on their operations, and their practices to mitigate the effects on the climate on the specific water systems.
Aside from kangkong, bamboo and coconut leaves are also used by some operators, putting them over the ponds to create a sort of umbrella. Others grow water lilies.
But only a part of the pond should be covered, and water lilies should be enclosed so they won’t spread to the entire pond, Zulueta said.
The heat is likewise resulting in worsening water quality in the ponds with more frequent incidents of low dissolved oxygen and low pH levels in the water.
“While low DO and pH levels were experienced in the past, these have become more frequent, according to the fishery operators. The fishery operators are resorting to frequent changing of the water to mitigate the problems,” he said.
The water would also benefit from the cooling effect of the plants because the water’s capacity to absorb oxygen is minimized when it is very hot.
“The fish’ eggs won’t also be fertilized, they would rot it if is too hot,” Zulueta said.
Fishcage operators in the sea are likewise adapting to the changing climate by strengthening their cages, as they are affected during typhoons. They also harvest early, or before typhoons come, to minimize losses.
Entry filed under: News.