Is the Cold Weather Putting the Chill on Taiwan Fish Stocks?

If you are an angler in Taiwan, you are probably counting the days until the Lunar New Year holiday for a chance at some uninterrupted fishing. Cold wet weather has no doubt put a damper on the angling plans of some this winter. So, if you’re like me, you are hoping for a slightly warmer, somewhat sunnier holiday week. You may also be wondering just what to expect when you do finally arrive at water’s edge.Unusually cold weather in Florida was blamed for killing large numbers of Tilapia and Peacock bass. Can Taiwan expect the same? Photo by Scott Wheeler, The Ledger.

Unusually cold temperatures prevailed throughout the northern hemisphere this winter and subtropical Taiwan hasn’t been spared. Even on the southern end of the island, usually immune to the seasonal chill, has seen temperatures drop into the single digits (Celsius). What impact the falling mercury will have on local fish stocks has yet to be determined, but everyone from anglers to fish farmers are getting nervous.

Not all local game fish and aquaculture species are sensitive to sharp fluctuations in temperature. Most native fish as well as some imports from temperate regions (largemouth bass and rainbow trout) should do OK. However, those species introduced from warmer climes could face mass die-offs. Tilapia, an important food fish and the backbone of the local aquaculture industry is probably the most at risk. The species stops feeding and reproducing as temperatures near 10˚ Celsius and begins dieing after that point. Mass weather-related kills of tilapia have already been reported in the U.S. state of Florida and in Haiti this month.

Another cichlid, the peacock bass, is also at risk. The prized South American game fish was introduced to Taiwan through exotic aquarium market and has become established several southern Taiwan ponds and lakes. Like its cousin the Tilapia, it is also extremely sensitive to drops in water temperature.

Freshwater fish are not the only one’s potentially affected. Milkfish, another important aquaculture species, is farmed in cement ponds filled with seawater. A mass kill could be economically devastating for farmers because domesticated milkfish take eight to ten years to reach sexual maturity.

For now, there is not much to do but wait and see. As of today, the mercury was up a bit, rising as high as 19˚ C during the day. However, it is expected to dip down to 7˚ C at night this weekend in Taoyuan, the heart of north Taiwan’s fish farming industry.