Earthworms perish en masse in Wayanad, portending severe drought?

Dead earthworms found in Wayanad

Panamaram, Wayanad: Earthworms have been found dead en masse at various places around Wayanad district, this year as well. Earlier, earthworms were found dead a few weeks after the monsoon showers. However, this time, the strange phenomena have occurred even before the rains subsided. The farmers have been worried after the earthworms began perishing in huge number in consecutive years. The farmers in Nadavayal and Kaykunnu areas noticed that earthworms wiggle out of the soil and die in large numbers.

The earthworms began dying soon after the rains stopped this year. However, the number of perishing earthworms has gone up since then. The farmers complain that long and healthy earthworms have been dying mostly. Earthworms dying on the roads and in the front yards of houses have become a common sight in most parts of the district. It is said that this phenomenon happens due to temperature variations in the soil.

Dr. Prashant Narayanan, senior research associate at Mahatma Gandhi University had found, three years ago, that earthworms die en masse when they try migrating to safer places. The Ambalavayal regional agriculture research centre too had attributed the phenomenon to excess heat in the soil.

Meanwhile, the farmers say that perishing of earthworms indicate severe drought in the coming years. Soil was collected from the places where earthworms died last year and experiments were conducted. It was revealed that these soils were rich in organic matter and nutrients. The acidic tests too indicated that the soils were extremely fertile. This has made the agricultural scientists and researchers presume that excessive heat may have caused the earthworms to die in large numbers.

The unique soil in the Deccan plateau expands and contracts due to temperature variations. Cracks are formed in the soil because of that. When the top soil loses moisture, the earthworms wiggle deep into the soil looking for cooler and moist soil. However, when they wiggle out of the soil, the earthworms perish due to extreme heat. The earthworms usually burrow 10 – 30 centimetres deep into the soil.

The recurring floods have washed away the organic matter and the soil loses the capacity to retain its moisture content. The earthworms can only survive up to 15 – 28 degree Celsius. When the temperature goes higher than this, they wiggle out and die. Temperature of around 30 degree Celsius was reported in many places in Wayanad immediately after the rains stopped in the months of March and April. However, agriculture experts assure that there is nothing to be worried about this unique phenomenon.