cwlogo

切換側邊選單 切換搜尋選單

Global Warming

The Great Food Exodus

精華簡文

The Great Food Exodus

Source:CW

Fish are shunning their traditional waters, bees are disappearing, grain prices are soaring... Climate change is profoundly impacting the global food chain, and Taiwan has no special exemption.

Views

99+

The Great Food Exodus

By Fuyuan Hsiao
From CommonWealth Magazine (vol. 436 )

In an unseasonably warm December, southern Taiwan's last mullet fishing vessel, the Lianchunman, sits idle on a maintenance platform outside Kaohsiung's Singda port, a symbol of the declining mullet catch off Taiwan's shores.

Over the past decade, the traditional northeastern winds have grown increasingly warm, leaving the hearts of mullet fishermen colder with time.

Warmer Seas Keep Mullet Away

"Warmer waters mean the mullets don't swim here any more," explains Huang Ching-hsien, the 70-year-old retired captain of the Lianchunman with a lifetime of experience in chasing mullet, as he peers out at the Taiwan Strait off Kezailiao fishing port in Kaohsiung County's Zihguan Township, just north of Kaohsiung City.

Mullets are extremely sensitive to water temperatures, and they head south to spawn in waters that heat up to between 20 and 22 degrees Celsius after early winter cold fronts pass through. But as the water around Taiwan becomes even warmer, the fish are no longer migrating as far south.

Traditionally, the mullet have always gone on a huge southern migration to avoid strong cold fronts that sweep down from the north of the Asian continent, entering the waters off Taiwan without fail every year in the 10 days before or after the beginning of winter. This was the season fishermen in southern Taiwan reaped "mullet gold" and when Huang's son, Vic Huang Chih-hsiung, prayed at a local temple for a big catch to cover the cost of his education.      

One long-standing tradition among Taiwanese fishermen is that for every 10,000 mullets caught, vessel captains would stand a national flag on the ship's bow. During the golden age of mullet fishing, ships would regularly return to port draped with four or five national flags. Even before reaching Kezailiao harbor, they would be welcomed by the sounds of firecrackers resonating in the distance. Once in port, the ships lined up to form a sea of flags, while the golden color of mullet roe glistened for tens of kilometers along Taiwan's coast from Jiading to Zihguan. 

Huang Ching-hsien still remembers earning as much as NT$12 million from one trip to sea, which was not only enough to support the families of 24 crewmen, but also earned him honors as one of Taiwan's "Top Ten Outstanding Fishermen."

Those days are long gone. National Taiwan Ocean University president Kuo-Tien Lee, who has studied mullet fish and their habitat for 20 years, says that Taiwan's mullet catches have declined from 2.6 million fish in their heyday to fewer than 100,000 fish today.

Much like the dramatic fall in mullet catches, Donggang bluefin tuna numbers have also plummeted. According to Lin Han-chou, chief of staff of the Donggang Fishermen's Association, this year's catch of bluefin tuna was not even a quarter of what it was a decade ago. Consequently, the price of the fish, especially popular around Mothers' Day in Taiwan, has soared from NT$200 to NT$500 per kilo.

Lee, who studies the impact of global warming on Taiwan's fishing industry, contends that aside from overfishing, catches of the cold-water migratory Pacific bluefin tuna have also been hurt by the increasingly strong warm currents from the south.   

Endemic Species in Intensive Care Unit

Climate change has transformed any species that walks, swims or flies into an environmental refugee, and it poses a severe challenge to the conservation of threatened species.

Aggressive efforts have been made to preserve Taiwan's critically endangered national treasure, the Formosan landlocked salmon, but conservation measures are still vulnerable to climate change, says Ching-ming James Wang, a professor in National Taiwan Normal University's Graduate Institute of Environmental Education, who has studied the species for more than 20 years.

The data he has accumulated over the years show that the streams which served as the salmon's main habitat, such as Yousheng Creek in the Cingjing agricultural district at an elevation of 1,500 meters, now get too warm for the salmon to survive. Because many of the trees bordering the creek have been cut down to grow fruits and vegetables, the sun's rays directly heat the water to temperatures as high as 21.5 degrees Celsius between March and June, far surpassing the 17 degrees the species can tolerate. 

As a result, even though the government has campaigned to conserve the Formosan salmon for the past 20 years, only in Cijiawan Creek, which runs between elevations of 1,700 meters and 1,900 meters, can the endangered fish be seen.

Wang notes that a species is considered endangered when there are fewer than 5,000 of its kind in existence. Despite desperate efforts to save the Formosan landlocked salmon, only 700 to 3,000 of the species, including small fish, exist today.

"The Wuling agricultural district is the Formosan landlocked salmon's intensive care unit. I monitor them around the clock in places where they still exist, and I feel like a doctor making his rounds," Wang says with emotion.

The Rice Crisis

The torrential downpours or severe droughts brought by climatic extremes have also dramatically changed the environment in which crops grow.

Chung-Ming Liu, the director of National Taiwan University's Global Change Research Center, says that while rainfall duration throughout Taiwan this year was only 85 percent of the norm, rainfall volume stayed steady. That's because Typhoon Morakot, which battered Taiwan for three days from Aug. 7-9, pushed total precipitation numbers higher.

Not even four months after the massive storm, however, southern Taiwan is again facing drought. Tsengwen Reservoir is already running low, with its storage level falling below 50 percent.   

Recently, the Water Resources Agency issued another warning that southern Taiwan's dry season had only just begun, with little rainfall expected over the horizon, and that the drought would become "extremely serious" early next year. At least one season of rice cultivation will have to be sacrificed to this all-or-nothing precipitation pattern, which has completely disrupted the natural shifting of seasons to which crops are accustomed.

In mid-November in central Taiwan's Wufeng, for example, winter has been seriously delayed, casting a shadow over Taiwan's rice production.

Yang Chwen-ming, a research fellow in the Crop Science Division of the Taiwan Agricultural Research Institute, who has observed the impact of a changing climate on crops for the past 15 years, observes that farmers have adjusted their practices to accommodate rising temperatures, planting their first season of rice earlier than before.

But if they plant their rice to accommodate an early spring and then temperatures suddenly fall, their yields will be low. The best example came in April and May in Taidong County, where an unexpected cold spell destroyed 80 percent of the area's rice crop, leading to heavy losses for local farmers.

The International Rice Research Institute has shown that when night temperatures rise by one degree Celsius, rice harvests fall by 10 percent. With global rice harvests falling short this year, the price of rice has doubled.

Aside from drought and torrential rain destroying grains, rising temperatures have also enabled plants' natural enemies to run rampant.

Ping-shih Yang, a professor in National Taiwan University's College of Bioresources and Agriculture, observes that the brown planthopper, a real menace to rice in Southeast Asia, has followed the warmer temperatures to gradually invade Taiwan, jeopardizing local rice crops as they proliferate in large numbers. 

Foreign Species Overtake Taiwan

It's not only the food on our table that is undergoing dramatic changes. Living creatures are also "voting with their feet," running for their lives to avoid extinction.

According to a report by the United Nations' Intergovernmental Panel on Climate Change, tropical species are migrating to temperate climates, and low-altitude species are migrating to medium elevations. It estimated that about one-third of the globe's known species would be extinct before the end of this century. With every one-degree rise in surface temperature, another 10 percent of the world's species face the threat of extinction, leading the United Nations to declare 2010 as the International Year of Biodiversity.

Plant ecology expert Chang-Hung Chou, the dean of China Medical University's College of Life Sciences and an Academia Sinica academician, stresses that species "flight" constitutes a major problem that threatens the world's survival.

A longtime observer of plant species on Taiwan's Mt. Hehuan, Chou discovered that the number of species on the 3,400-meter high mountain have soared from around 60 more than 10 years ago to 90 today. He believes this growth can be directly attributed to climate change, which has triggered a massive migration of low-altitude plant species to higher elevations and destroyed the area's ecological balance. 

Chou acknowledges that species migration on the surface bears no relation to the average person's life, but he says that this biological "change in power" has destroyed Taiwan's endemic biodiversity, causing "outsiders to overtake Taiwan." He also notes that warmer temperatures lead many plants to bloom earlier and lengthen the flowering season, setting off an ecological chain reaction by spurring greater activity among pests, which in turn spread pathogenic bacteria.

Disappearance of Bees Spells Crop Disaster

Also hurt by irregularly blooming flowers are bees, nature's key agricultural catalysts.

Over the past two years, areas around the world have been plagued by the mysterious disappearance of bees, which has triggered curiosity among scientists and panic among farmers. In 2007, 80 percent, or about 7 million boxed hives, of the bees on the West Coast of the United States mysteriously vanished, prompting the U.S. Congress to hold a special hearing to investigate the cause of the phenomenon, called colony collapse disorder (CCD).

Without bees pollinating, apples, corn, wheat and most other important crops cannot grow. The losses stemming from the disappearance of bees have been estimated at NT$480 billion.

Huang Tung-ming, head of the Yilan County Beekeepers' Cooperative, has particularly strong feelings about climate change. He contends that rising temperatures have disrupted bees' navigation systems and may be one of the factors leading to colony collapse disorder. A few years ago, the tens of thousands of bees Huang had raised disappeared without a trace in a single week. Not even their corpses were left behind.

Huang feels that in recent years, Taiwan's blooming seasons have gone haywire, causing worker bees to fight harder to get access to flower and honey and shortening their life spans from 60 to 20 days. As a result, bee production has fallen by two-thirds over the past five years.

The disappearance of bees, Huang insists, is a major issue, because 90 percent of the more than 1,300 crop species necessary for human survival are pollinated by bees. Aside from betel nut and pineapple, Taiwan alone has more than 40 types of fruits and vegetables that rely on the pollination of bees.

"Without bees, plants will grow deformed fruit," Huang says. That would be catastrophic, because while the value of direct output by bees in Taiwan approaches NT$1 billion, they are also indirectly responsible for NT$50 billion worth of agricultural crops.

Strengthening Research to Combat Warming

With plenty to lose from climate change, Taiwan is one of the world's pioneers in looking for ways to help plants adapt to a warming climate.

Rice expert Dah-Jiang Liu, the director-general of the Taiwan Agricultural Research Institute, says Taiwan in fact got an early jump on confronting the impact of climate change on agriculture. For instance, Taiwan originally only grew the indica variety of rice, but introduced japonica rice from Japan over 100 years ago, making it the southernmost latitude at which the subspecies was grown. As a result, Taiwan's japonica rice is now better able to withstand heat than japonica varieties grown elsewhere.

Temperate fruits such as apples, pears and peaches that in the past could only be grown in Taiwan's mountainous areas are now cultivated in low-lying areas. Liu says that Taiwan has also raised low-chill varieties of temperate fruit trees at higher minimum temperatures than any other country in the world. "We have already adapted them to warmer temperatures," he explains.

Liu openly acknowledges, however, that if temperatures continue to rise, it will affect the livelihoods of tens of thousands of farmers in Taiwan who currently cultivate NT$12.5 billion worth of temperate fruit trees. The Taiwan Agricultural Research Institute's current mission, Liu says, is to develop even more temperature-resistant fruit tree varieties, as well as crop varieties that are better able to withstand high temperatures, drought and disease and are more salt-tolerant. 

He worries, though, that increasingly high temperatures will affect water supplies, because water shortages could disrupt Taiwan's harvests of rice, the country's most self-sufficient crop. Thus, his institute is presently engaged in developing drought-resistant rice strains and strengthening rice's ability to survive adverse conditions.

Springs without bees. Winters without mullets. Some people may believe that these phenomena have nothing to do with their daily lives. But nature's changing course not only limits the diversity of our food chain, it will also decide the fate of humanity. We all have become the new refugees of climate change.

The question is no longer, "What's for dinner?" but, "What's still left to eat?"

Translated from the Chinese by Luke Sabatier

Keywords:

好友人數