A high-pitched shriek by the hoolock gibbon warns of heavy rains within a few 
hours, even on a sunny day
A high-pitched shriek by the hoolock gibbon warns of heavy rains within a few hours, even on a sunny day

How Sumi Nagas’ traditional knowledge helps them navigate nature’s vagaries

The Sumi tribe of Nagas uses several ecological indicators to facilitate agricultural practices and predict seasonal variation; but this wisdom is vanishing with the passage of time

One bright sunny morning, residents of Shiyepu village in Nagaland’s Zunheboto district, head to church dressed up in their Sunday best and carrying umbrellas. The latter accessory is perplexing, given the clear weather.

But the church-goers know something that even weather forecasters do not—bees in the village (both Asiatic honeybee or Apis cerana and stingless bee or Trigona iridipennis) did not leave their hives that morning, indicating a prospect of rain. Sure enough, it soon starts to drizzle.

This premonition is just one bit of a vast body of knowledge that the Sumi Naga tribe has gathered through generations of observation and passed down orally and through cultural practices.

But there is little to no documentation about this traditional knowledge and so it is at risk of being lost. As a PhD scholar at Martin Luther Christian University in Shillong, I undertook a study of 10 villages in Zunheboto, which is primarily inhabited by the Sumi Naga tribe.

Over three years, I recorded 79 ecological indicators (biotic and abiotic) that the community depends on to determine weather anomalies, seasons and natural disasters, even in the age of complex numerical climate models.

For instance, apart from the locally reared bees the Sumi community uses bamboo, a culturally significant grass in Nagaland, for multiple weather clues. If new shoots of the Phyllostachys genus of bamboo rise higher than the parent plant, one can expect heavy rainfall during the monsoon season that year; if they stay low, less rain is likely.

Similarly, flowering of the Bambusa pallida species indicates famine, as it attracts rodents that damage crops.

Ashili Awomi, a resident of Litta Old village in Zunheboto, recalls how the Sumi Nagas warned of an impending famine in the nearby Mokokchung district in 1962, after they observed gregarious flowering of Bambusa pallida and a sudden rise in the stink bug (Encosternum delegorguei) population.

Residents there then stored and consumed wild yam and forest tubers. Inconspicuous events like spontaneous barking of dogs or rodents emerging from holes can also indicate natural disaster, as seen during the December 2020 earthquake in Nagaland, says Kakuto Shohe of Sohomi village.

Agrarian clues

The Sumi Naga community is primarily agrarian and depends on forests for both food and livelihood. So several of the indicators facilitate agricultural practices and predict seasonal variation.

For instance, fruiting of mulberry (Morus) trees indicates spring and their harvest means summer is here. Then, to predict winter, the Sumi tribe uses a universal, reliable indicator—migrating birds.

The arrival of wag tails (Motacilla) from eastern Asia and Amur falcons (Falco amurensis) from Siberia to Nagaland in October every year, enroute to Africa, means winter is nigh.

I found that people in the community also look closely at catfish (Siluriformes) caught locally. Unusually thick skin on the fish’s stomach indicated an above normal winter.

Rainfall is crucial in determining agricultural yield, so a whole range of natural indicators predict its arrival. For example, the song of the cuckoo (Cuculus canorus) tells farmers to start sowing.

While making a fire, if smoke rises unswervingly, the weather will be clear. A night sky full of stars also signals dry weather. In contrast, expect rain the next day if the crescent of the moon faces down or has a halo around it.

Although such tricks are handy, observing the behaviour of different life forms around them also gives the Sumis the clues they need. Pine cones (Pinus) opening their scales indicate dry skies while bitter tomato (Solanum aethiopicum) plants shedding leaves indicate onset of rain.

There will also be rainfall if wood borer larvae (Buprestidae), a type of beetle that dwells on trees, settle at the top of the plant and eat their way down.

Conversely, if red weaver ants (Oecophylla) leave their nest open and facing up, they expect no rain. Cicadas (Cicadoidea) come to the region from May to November; the volume of their song indicates how much rainfall to expect.

The Sumi Naga tribe believes that amid rainfall, if domesticated chickens (Gallus gallus) leave their coop, wet weather will persist all day.

“Fish, too, can sense rain. Once at the pond near my house, my son saw several fish (Chondrichthyes) swimming to the surface; this meant rain was on its way. It was a signal for us to head back home,” explains Husheto Achumi of Khukiye-Lukhai village.

One other reliable indicator the Sumis depend upon is the hoolock gibbon (Hoolock hoolock). A high-pitched shriek by the primate, even on a sunny day, warns of heavy rains within an hour or two. However, it is now endangered in the region because of poaching.

Elders in the community say that the ecological indicators help them predict weather even in a changing climate. But the skill is rapidly disappearing with the demise of the community’s elders and the lack of documentation.

With the migration of youth to urban areas for education or employment, they neither know nor care about the natural indicators.

Alino Sumi is senior researcher at the Archaeological Sciences Centre, Indian Institute of Technology, Gandhinagar

Down To Earth