District aquatic breeding farm has fish to fry

Tan Weiyun
An aquatic breeding farm is celebrating after the first batch of fry from Songjiang Bass successfully hatched.
Tan Weiyun
District aquatic breeding farm has fish to fry

The pink egg masses of Songjiang Bass

AN aquatic breeding farm is celebrating the first batch of Songjiang Bass fry successfully hatched.

Songjiang Bass is famed as the "No.1 famous fish in the southern bank of the lower reaches of the Yangtze River."

The Shanghai Songjiang Aquatic Breed Farm in Xiaokunshan Town has been spearheading the conservation and breeding of this distinguished species.

Visitors to the farm are first greeted by an intriguing sight in the breeding pools: overturned clam shells meticulously arranged at the bottom.

These serve as cozy nests for the spawning Songjiang Bass, a clever set-up by the farm's technicians.

Closer observation reveals adult fish elegantly navigating around their clam shell homes.

Meanwhile, in the hatching pools, nets encase pink egg masses that have been carefully harvested.

A closer examination under the beam of a flashlight uncovers numerous eggs already showing pairs of black dots - the embryonic eyes of the Songjiang Bass.

Those further along in their development journey have emerged from their membranes, sprouting tiny tails and exhibiting agility as they navigate the waters.

At this tender stage, the fry are tinier than grains of rice, their bodies a delicate pinkish-transparent hue, resembling minuscule tadpoles under the light's glow.

The Songjiang Bass is a migratory species, venturing to estuaries where saltwater meets freshwater during its spawning phase.

Remarkably, the species practices monogamy, with females laying eggs and males vigilantly guarding them, never straying from their nests, embodying the "model couples" of the fish world.

"To create a conducive environment for spawning, we not only use clam shells for nesting but also maintain the hatching pools' water slightly saline, different from the breeding pools, to simulate their natural habitat," said Gong Guangwei, the farm's technical director.

Spawning began on February 3, with the earliest fry already making their entrance. Thousands have hatched, and the farm anticipates a yield of 300,000 to 400,000 fry. In approximately 40 to 50 days, these fry will grow to 2 to 3 centimeters in length.

The newly hatched fry require immediate transfer to nursery pools, necessitating Gong's daily monitoring of egg mass collection and close observation of egg development within each net cage.

"With the season's temperatures on the rise, the hatch rate is expected to increase accordingly," Gong said.

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