By: Rajesh Sanap, Kiran Marathe, & Anuradha Joglekar
Although high temperature brings most forest activities to a halt, certain insects such as cicadas keep the forest alive with their songs even during hot summers!
Cicadas are the insects of the order Hemiptera, with nearly 1300 species known worldwide. In folklores, cicadas have been depicted as symbols carefree living and immortality. Cicadas are popularly known for their periodic emergence, and interestingly, while most cicada species emerge annually, some emerge once in as long as 17 years.
The life cycle of a cicada comprises three stages—egg stage, a long fossorial nymph stage, and a short adult stage. Adult males produce peculiar acoustic signals to attract female mates. The unique membranous structures on the sides of their abdomens called tymbals enable cicadas to produce calls, which are species specific. The life-span of adult males is very short, and most individuals die immediately after mating. Females lay eggs on tree barks. Upon hatching, the larvae drop to the ground, where they complete the nymphal stage. In their final instar, the nymphs crawl above the ground and molt into the adults.
In ecosystem, cicadas are important sources of nutrients for birds, reptiles, and even other insects. Like other hemipterans, they feed on tree sap.
To date, five species of cicadas have been recorded from Aarey Milk Colony. However, researchers have reported deforestation, soil erosion, urbanization, and habitat loss as few of the potential threats to these insects. The production of song is crucial for successful reproduction in cicadas, and high levels of ambient noise as a gift of urbanization has rendered the cicadas silent.
To explore the biology and diversity of these interesting insects, please visit Cicadas of India available at the following link: www.indiancicadas.org