India Girds for Famine Linked With Flowering of Bamboo

Pallava Bagla
for National Geographic News

June 22, 2001

NEW DELHI, India—The Government of India is working on an emergency
plan to address a regional food shortage and related famine that is
expected to occur two years from now when vast forests of bamboo burst
into flower.

Some species of bamboo flower only every 40 to 50
years. In an intriguing chain of events, these periods of flowering
sometimes lead to the destruction of basic crops, and subsequent
widespread famine, in areas of India where bamboo grows heavily.

The last famine of this nature occurred from 1961 through 1965 in the hilly state of Mizoram in eastern India, an area of 21,000 square kilometers (12,482 square miles) with a population of more than 700,000.

Reports suggest that another cycle of heavy bamboo flowering will happen in the region in 2003, which prompted India to call an emergency meeting of its national planning body last week to prepare for the possible calamity.

There are hundreds of species of bamboo in the world. Some flower every year, some at irregular intervals. But a small percentage flowers in synchrony, over hundreds of square kilometers, every few decades. Researchers aren't sure how it happens.

"Science has to date not been able to explain how the same message is passed among bamboo clumps separated by hundred of kilometers to flower at the same time, said botanist H. Y. Mohan Ram of the University of Delhi, who is one of the country's foremost authorities on bamboo.

He speculates that the rhizomes of the bamboo have some kind of "memory" trait that makes the plants grow in synchronization, then burst into bloom all at the same time. After the massive flowering, the bamboo clumps die, in what Mohan Ram calls "a kind of suicide by over-production."

How does all this lead to famine?

Rodent Marauders

When bamboo plants flower, they produce a large volume of seeds, which are a source of food for many predators, especially rats.

As masses of flowering bamboo produce this natural bounty, rats are attracted to the area. Fortified by the protein-rich seeds, they multiply rapidly.

But the supply of bamboo seeds is limited. When it is exhausted, armies of these marauding rodents turn their attention to standing crops, devouring acres of rice, potatoes, and sweet potatoes within a few days. As a result, local peasants, who are fully dependant on agriculture for their sustenance, are subject to famine.

The phenomenon occurs mainly in Mizoram, which is heavily covered with two species of bamboo (scientifically known as Bambusa tulda and Melocana bachiphera). The impact can be so devastating that local folklore is full of tales about this natural cyclical event.

Prevention Efforts

B. Hari Gopal of India's Department of Science and Technology in New Delhi was one of the first scientists to investigate cyclical bamboo flowering and the associated growth in rat populations.

The surge in the number of rats, he explained, "could be attributed to a reduction in cannibalism and the shortening of the time gap between pregnancies as a consequence of an abundant supply of highly nutritious food."

The local administration has tried to curb the proliferation of rats by offering a monetary award for killing them—equivalent to U.S. $2.50 for every 100 rats killed. The rats' tails are submitted to officials as evidence that the animals have been killed.

Hari Gopal said that when the most recent cycle of bamboo flowering in the region began, villagers were killing about 500,000 rats a year. By the time the flowering peaked about two years later, the number had risen fivefold, to 2.6 million rats killed each year.

Hari Gopal and other scientists are working to better understand the links between bamboo flowering and famine. Meanwhile, the Indian government is devising a plan to deal with a cycle of bamboo flowering and famine that is expected to occur in 2003.

The state has been ordered to greatly increase stocks of food in the region and to store these provisions in rodent-proof silos.

D. N. Tiwari, a member of the government's Planning Commission, said officials were also considering other measures, such as replacing flowering varieties of bamboo with non-flowering ones.

Mohan Ram views such an approach as "outlandish." He believes the only way to avert the cyclical famine associated with bamboo flowering is to teach farmers to plant crops that rats do not eat, such as ginger and turmeric, during the periods when vast fields of bamboo are expected to flower.