On a green trail

Monsoon marks the beginning of something new.

CHENNAI: Monsoon marks the beginning of something new. The green cover looks fresh and full. There is enough water to drink and food to eat for all creatures.

As the city rejoices the unexpected showers, new batches of critters have already begun bursting from their pupae and turning into butterflies, moths or bees, ready to pollinate.

These are hints of a healthy ecosystem. Species of flora and fauna that react naturally to the new environment are known as bio-indicators.

In places with more forest cover like IIT- Madras, Women’s Christian College, Guindy National Park, and Madras Christian College, such species have already begun dropping hints...we just need to pick them up.

Naaz Ghani talks to naturalists Vikas Madhav and N Mahathi, who share seven bio-indicators you can look for to confirm a thriving ecosystem.

DAMSELFLIES

• Close cousins of dragonflies, this species folds its wings neatly behind its back. Their slender, iridescent blue bodies shine in the sunlight.
• Damselflies are normally indicators of a healthy tropical ecosystem and often make appearances during the monsoon season.
• They can survive in specific conditions. A wet, leafy and unpolluted environment is most suitable.
• They are often present in areas with rainforest or estuarine ecosystems.

FROGS

• Tadpoles can be spotted in the smallest of puddles, especially in certain areas behind the IIT Madras campus and in Taramani.
• They indicate a healthy water and forest environment.
• Similar to moths, the spawn of these amphibians can only survive in certain conditions apt for survival.
• One can expect to spot reptiles and a variety of moths when frogs are around.

BUTTERFLIES

• Found in the dense forests, like those of the Western Ghats.
• Present in areas with undisturbed ecological balance and well-functioning ecosystems.
• Sensitive to hot temperatures and prefer to stay in cool environments.
• One example of an indicator is the bright orange and yellow butterfly — The Cruiser. It has only been spotted twice in Chennai in the 2015 floods and during the heavy rains of 2017.
• It was spotted in Indira Nagar and Adyar due to the thriving forest ecosystems in the Guindy National Park.

CENTIPEDES AND MILLIPEDES

• These insects are burrowing creatures.
• They can be seen after the rains, searching for a suitable habitat, because their underground tunnels get flooded.
• Both are known to release a specific musky smell after congregating in the rain.
• They feed on decaying plants, wood and tiny insects, which are plentiful after a shower.
• Centipedes are faster, more aggressive predators and have fewer legs, while millipedes are slow and have more of a foraging nature.

MOTHS

• They hatch during the monsoon so that their caterpillars turn into butterflies by the time the flowers bloom.
• The pupae of these moths react to the environmental surroundings and allow the adult winged insect to release itself only when the conditions are apt.
• Because of the aforementioned characteristic, moth larvae are also one of the first bio-indicators of an upcoming monsoon.
•  Fewer moths in an otherwise ecologically strong area, like a forest patch, indicate shorter rainfall.

TREE MOSS/ LICHENS

•  Often seen as light green patches on the bark of a tree.
•  Lichens are made up of a particular fungus and algal bacteria.
•  In case of high nitrogen levels in the air or extreme temperatures, the microorganisms die, leaving the patch looking white and grey as compared to a healthy light green colour.
•  During monsoon, the patches are green and white, with a few hints of brown.

SNAILS

•  During the monsoon season, one can see snails in an ecologically rich area, especially in a forest or river ecosystem.
•  They co-exist with slugs and earthworms, and prefer tree cover.
•  These creatures are extremely sensitive to temperature.
•  They are most often spotted just before a bout of rainfall.