Tag: GS 3 ||Environment || Biodiversity || Animal Diversity

Why In News?

Indian bullfrogs which were introduced in the Andaman islands are invasive and eating native wildlife including fish and lizards.

What are invasive species?

An invasive species is a species that is not native to a specific location (an introduced species), and that has a tendency to spread to a degree believed to cause damage to the environment, human economy or human health.

Indian Bullfrog

The Indian bullfrog

It now shares space with another native (and often endemic) frog species.

The bullfrogs are prolific breeders: they have short breeding seasons.

Its tadpoles are carnivorous and eat other tadpoles (including their own species).

The bullfrog is found widely in mainland India and protected under Schedule IV of the Indian Wildlife Act 1972

Invasive nature

The large bullfrog tadpoles eat other native frog tadpoles.

The survival of both endemic frog tadpoles reduced to zero when bullfrog tadpoles were present.

The proportion of bullfrog tadpoles surviving was greater

This is worrying other for native frog species.

Man-Frog conflict

The voracious animal gulps down anything that would fit in its jaws: centipedes, leeches, native frogs, lizards, small snakes, and even chicks and ducklings, which are an important source of food for theIslanders.

Why are bullfrogs a threat on islands?

Bullfrogs are found all over mainland India, but it is in the unique ecosystem of the islands that it becomes a major threat

all over mainland India, but it is in the unique ecosystem of the islands that it becomes a major threat Unlike the mainland, resources on the islands are scarce for big animals, while natural calamities are more frequent

resources on the islands are scarce for big animals, while natural calamities are more frequent The wildlife here has evolved in a miniature setting: there are no large herbivores (the largest is the Andaman wild pig) or large carnivores

Focus on invasive species

Globally, invasive species , particularly in islands, are becoming the focus of numerous organisations

, particularly in islands, are becoming the focus of numerous organisations The Convention on Biological Diversity has said that invasives have contributed to 40% of all animal extinctions since the 17th century

The IUCN has formulated guidelines for managing invasives specifically in islands, largely involving data collection, community engagement, policy measures and management plans

Additional References

https://www.thehindu.com/sci-tech/science/indian-bullfrogs-take-to-invasive-behaviour-early-in-andamans/article26898389.ece

Mains Question

Invasive species and threat posed by bullfrog on native species and biodiversity.Comment.