At 6 a.m., the fishing boats have just returned to the harbor of Nanfang’ao in Yilan County. But the mood at the harborside is somber.

“Nangang’ao has 50 to 60 fishing fleets catching mackerel. In the past, we could catch 800 tons in a day, but yesterday some boats did not even catch one ton,” says a street hawker. 

Nanfang’ao used to be called the “hometown of mackerel”. This is because not far from its coast is a rising ocean current that meets the Japan Current, also known as Kuroshio. The rising current pulls large quantities of small fry, shrimp and seaweed up from the seabed to the surface, attracting mackerel that are migrating south from the north to lay eggs. As a result, Nanfang’ao has long thrived on mackerel fishing.

The fishing industry in Nanfang’ao is facing a challenge (Source: Ming-Tang Huang)

Liao Ta-ching, the 70-year-old head of the Nanfang’ao commercial district development association, recalls that during his childhood the fish were so abundant that nets were always full. Back then the fishing boats would set sail three times a day.

However, these plentiful times are long gone.

Three years ago, Asoka Lin, Chief Executive Officer of the Taiwan Ocean Conservation and Fisheries Sustainability Foundation (TOFF), began to assist the Fisheries Agency in monitoring the catches in Nanfang’ao in all weather conditions.

In March, she received calls from fishermen who asked for help. “The fishermen said the mackerel are not migrating south to spawn, and they wanted us to help find out why,” Lin says.

So where have all the mackerel gone?

Lu Hsueh-Jung, professor at the Department of Environmental Biology and Fisheries Science at National Taiwan Ocean University (NTOU), notes that mackerel stocks were nearly depleted some ten years ago. After a seasonal fishing ban was implemented in 2013 for five years, stocks showed some recovery.

But the situation began to deteriorate again in 2019.

Even small mackerel not returned to sea

At the office of the Taiwan Mackerel Fisheries Association, fishing boat captains in their forties are blaming the crisis on other fishermen who do not care about the sustainability of the industry. Since they even catch small fish, stocks are drying up.

Picking up a small mackerel the size of a hand, one bursts out in anger: “They even catch all the fry, so we will be left with nothing in the future.”

Under Fisheries Agency regulations, fishing is banned for a month every June to ensure that the young mackerel that have hatched in the spring have an opportunity to mature.

But in early May, Huang Hung-cheng, a local captain, discovered that some fishing boats were still catching small fish.

A two-year-old Mackerel can grow to 30 cm, better on the quantity and price. (Source: Ming-Tang Huang)

One of the captains chimes in: “I am 40 now and need to catch fish for another 20 years. How can we manage our industry sustainably if the sea is fished empty now?”

In recent years, many young fishermen have voiced hopes for a transformation of the fisheries environment. Eager to break the vicious cycle, they want to follow Japan’s example and process their catches into high-end foods that fetch a good price.

Still, while most fishing crews in Nanfang’ao keep their commitment to catch fewer fish, this is not necessarily the case for mackerel fishing fleets from Keelung and New Taipei City. Uniting all behind the case of more sustainable fishing is not an easy task.

Mackerel are usually canned, pickled, or sold as fillets. But less marketable fish with flaws, or mackerel that are too small, are processed into animal feed.

As a migratory species, the distribution range of mackerel comprises the East China Sea, the Bohai Sea, and the western coast of Japan’s southern main island of Kyushu. Fishing fleets from China, South Korea, and Japan are therefore also catching mackerel. Japan and South Korea have also registered declining mackerel catches in recent years. Local fishermen are most concerned about large Chinese fishing fleets that catch mackerel in huge quantities.

Huang, the local captain, says more than a thousand Chinese fishing boats are fishing for mackerel in waters near the disputed Diaoyutai Islands group (Senkaku Islands in Japanese) with purse seines - large walls of netting deployed around an entire area or school of fish.

In the end it doesn't matter who catches the fish. It is the overfishing resulting from industrialized fishing methods that threaten fish stocks. Although mackerel grow fast, fish stocks might be completely depleted if they are not managed appropriately.

With warming oceans, mackerel no longer need to migrate south in winter

The problem of overfishing is compounded by rising ocean temperatures, which change migration patterns.

Over the past three decades, the temperature in Taiwan’s coastal waters has risen more than 0.7 degrees Celsius, twice the average temperature increase for the world’s oceans.

For Taiwan’s coastal fisheries, this is a disastrous development since many fish species commonly consumed in Taiwan such as mackerel, eel, tuna, and mullet are migratory fish. If ocean temperatures continue to rise, these species, which used to migrate to Taiwan during specific seasons, might not show up in waters off Taiwan anymore.

Fish are very sensitive to water temperature. As fishermen point out, a difference of just one or two degrees Celsius can cause entire schools of fish to change course.

NTOU Vice President Lee Ming-an notes that the latest scientific estimates expect countries at high latitudes to benefit from rising ocean temperatures because some migratory fish species might no longer migrate south during the cold season. Their fishing resources might increase by 70 percent, whereas Taiwan and other subtropical areas could see the output of their local fishing industry drop by 40 percent.

Scientists also speculate that the scarcity of mackerel in Taiwanese waters this year could be related to rising ocean temperatures.

Professor Lu says the mackerel species commonly caught off Nanfang’ao are Pacific chub mackerel (Scomber japonicus) and spotted chub mackerel (Scomber australasicus). The Pacific chub mackerel, which prefers colder waters, accounts for a declining share of local catches.

“Before, the Pacific mackerel accounted for 40 percent of the mackerel catches; now we are left with just 10 percent. The ratio has been declining for a decade. What this tells us is that the border of the range where migratory fishes go has been moving north,” Lu explains.

Marine resources, already depleted by industrialized fishing and overfishing, are now on the brink of collapse due to climate change.

Liao, who used to organize the Nanfang’ao Mackerel Festival, an annual tourism attraction, is very worried that mackerel could disappear from Taiwan’s coastal waters. It would deal a deadly blow to local culture and tourism.

“We must not let the hometown of mackerel turn into their burying grounds,” he says.

Should the mackerel stay away, the fishermen, too, would need to find other ways to earn a living.

Some believe that fishing should be reduced during the spawning season in February and March. Lin, who has been involved in the conservation of marine resources for many years, believes that restricting total catches must be considered as a possible approach.

As Liu Chia-chen, deputy head of the Fisheries Regulation Division of the Fisheries Agency, points out, catches in Taiwan have remained stable over the past years at around 70,000 to 80,000 tons per year. Fishing boats are required to log their catches upon return to the harbor, a requirement that most fulfill as the reporting rate is quite high. Liu says the policy will be adjusted after different opinions within the industry have been heard and reconciled.

Beyond these measures, the fishermen set their hopes in transnational cooperation for the conservation of fishing resources. Liu notes that Taiwan, Japan, and China used to negotiate over these issues, but the coronavirus pandemic and deteriorating cross-strait relations have made international cooperation difficult. 

Only if renewed efforts are made for fisheries negotiations with Taiwan’s neighbors can Nanfang’ao stand a chance to welcome mackerel in the future.

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Translated by  Susanne Ganz
Edited by TC Lin
Uploaded by Ian Huang