Can animals and plants predict the monsoon? Indigenous forecasting methods from Tamil Nadu and Manipur

Can frogs, cuckoos, and flowering neem trees predict the rains? For generations, farmers, fishers, and forest dwellers in Tamil Nadu and Manipur have relied on such signs to anticipate the monsoon—long before satellite forecasts and weather apps.

In many parts of India, especially among rural and indigenous communities, monsoon forecasting isn’t just about Doppler radars and weather apps. It’s about observing nature — the blooming of neem trees, the chorus of frogs, the flight of termites, and the calls of birds.

For generations, farmers, fisherfolk, and forest-dwellers have relied on animal behaviour and plant cycles to predict when the rains will arrive. These methods, passed down through oral traditions, are rooted in close observation and intimate knowledge of local ecologies.

This indigenous weather forecasting uses bioindicators. Their insights could complement modern climate models and support more adaptive, locally tuned responses to a changing climate. These forecasts often involve a deep study of the local surroundings, a deep connection and observation of nature and seasons over many years derived from an intimate interaction with the microenvironment whose rhythms are intertwined with the cycles of seasonal changes.

Nature’s clues to monsoon rains

Local indicators and local knowledge systems cannot be totally replaced with scientific knowledge, because they are holistic and specific to local situations, providing farmers and others with the ability to make decisions and prepare for the coming agricultural year. Despite the presence of modern technology to predict the weather, local knowledge derived from these deep observations of nature and its surroundings forms an important part of local weather forecasting and needs to be acknowledged. It can greatly help in supplementing and enriching scientific knowledge based on predictions and observations. 

In this article, we share some examples from two studies on how farmers from Tamil Nadu and ethnic communities from the Bishnupur district of Manipur in the Northeast observe the behaviour of some plants, insects, and animals to predict the monsoon and plan their activities accordingly.

One study is titled “Indigenous knowledge of weather forecasting with the aid of bioindicators in Tamil Nadu” by S. Usha and T. Mahesh. The other study is “ Animals as weather-forecasting bio-Indicators: A case study of different communities of Bishnupur district, Manipur, NE India,” by Th. Ajita Chanu , Robindro Teron , O. Shashi Kumar Singh, and H. Tombi Singh.

Birds that sing the rain

The calls of the lesser coucal and the common cuckoo can signal the arrival of rains

The Lesser Coucal is a type of cuckoo found in India, particularly in the northeast region. They nest from May to September but mainly after the rains in June in India, and they build their nests by using a dome of grass blades on a low tree. The calls of the lesser coucal include a series of low double "whoot-woot" or "kurook" notes that increase in tempo and descend in pitch.

The Common cuckoos live in forests and woodlands, grasslands, meadows, shrubland, heathland, reedbeds, open moorlands, and cultivated areas They are shy birds that lead a solitary life but become noisy during the breeding season, and the male song sounds like 'goo-ko' and is usually given from an open perch.

The chirping of Barbets

The blue-throated barbet lives in evergreen and deciduous forests and calls frequently throughout the day. Due to its green colour, it blends into the canopy, so the loud, frequent calls are often the only indication of its presence. The calls consisting of the notes took-a-rook, pu-ku-ruk, kut-ru-uk are repeated 90-105 times per minute 

The blue-eared barbet lives in shrublands and forests and nests in tree cavities. The male's territorial call is a repeated loud ko-turr. Other calls include a whistle known as the "policeman whistle.”

The Weaver Bird's forecast

Weaver birds are known to weave intricate nests, and flocks of these birds are found in grasslands, cultivated areas, scrub, and secondary growth. These nest colonies are usually found on thorny trees or palm fronds, and the nests are often built near water or hanging over water, where predators cannot reach easily.

Breeding behaviour of lapwings signals the approach of the monsoon

Lapwings usually appear in pairs or flocks in well-watered surroundings, ploughed fields, grazing land, and margins and dry beds of tanks and puddles and also in forest clearings around rain-filled depressions. They run about in short spurts and dip forward to pick up food. They are uncannily vigilant, and are the first to detect intrusions and raise an alarm and respond noisily with a loud scolding that sounds like Did-he-do-it? call. They nest on the ground and scrape, laying three to four camouflaged eggs.

Amphibians, insects, and other rain whisperers

India has a high diversity of termites. There are two types of termites. Some build mounds or nests in the soil, while some live in sponge-like, diffused chambers and act as pests, infesting buildings, agricultural crops, forestry, and horticultural and plantation crops. New colonies are formed by swarming, in which large numbers of winged individuals leave the parent colony. Swarming occurs twice in a year, once during April–June and again in September – October. Many form swarms coinciding with the rains

Frogs and toads croaking in chorus

Toads breed in still and slow-flowing rivers and temporary and permanent ponds and pools. Adults are usually under rocks, leaf litter, and logs, while their larvae are found in still and slow-moving waterbodies. They breed during the monsoon, and young toads may be seen in large numbers after monsoon rains finish.

Movement of dragonflies

It is most commonly seen from June to September but can still be around in November. Often seen patrolling around ponds, lakes, and other still water. Eggs are inserted into plants or in mud and hatch out in two months. Larval development takes two years. At the end of its larval stage, a dragonfly crawls out of the water; then, its exoskeleton cracks open and releases its abdomen, its four wings come out, and the body dries and hardens over the next several hours.

Fireflies on trees

Fireflies are found in temperate and tropical climates. Many live in marshes or in wet, wooded areas where their little ones can access food. All firefly larvae glow in the dark, but only some glow in their adult stage and the location of the light organ can be different among different species and between sexes of the same species.

Centipedes shift their eggs to safer places

Centipedes are elongated, segmented animals with one pair of legs per body segment. They require a moist microhabitat because they lack the waxy cover that insects have, causing them to rapidly lose water. They thus avoid direct sunlight by staying under cover or by being active at night.

Neem trees in bloom

It is one of the most celebrated and valued trees in India, known for its medicinal properties and has rich reserves of limonoids, known for their insecticidal properties. The mature seed kernel and fruit contain the high amounts of limonoids and are used in medicines as well as in making natural insecticides. 

Flowering of the babul tree

The Babul tree holds deep cultural significance in India and its  bark, leaves, and pods have been utilized for centuries in traditional medicine The tree's nitrogen-fixing ability enriches soil fertility and its nutritious foliage serves as a valuable forage resource for grazing animals.

Why this knowledge matters

Indigenous weather forecasting is hyper-local, deeply adaptive, and built on generations of lived experience. While modern meteorological models offer high-tech predictions, they often face the limitation of capturing microclimatic nuances.

Blending local bioindicators with scientific models could strengthen early warning systems, improve agricultural planning, and make communities more resilient to climate uncertainty.

These knowledge systems are especially valuable in the context of climate change, where historical weather patterns no longer hold and adaptive strategies rooted in place-specific cues are more important than ever.

References:

1. Chanu, A.T., Teron, R., Singh, S.O., Tombi Singh, H. (2019) Animals as weather forecasting bioindicators: A case study of different communities of Bishnupur district, Manipur, NE India. International Journal of Advanced Research, 7(5), 502-509.(This is an Open access article under a creative commons license)

2. Usha, S., Mahesh, T., Chitrambigai, K. (2025) Indigenous knowledge of weather forecasting with the aid of bioindicators in Tamil Nadu. International Journal of Veterinary Sciences and Animal Husbandry 2025; SP-10(1): 01-05. (This is an Open access article under a creative commons license)

Disclaimer: The observations in this article are based on two studies done in Manipur and Tamil Nadu and may not represent the views of the India Water Portal.