Domestic Cats — Threat to Island Biodiversity

Historically, the domestic cat has accompanied human beings to all the different islands he’s colonised. And history is proof that this cute animal has decimated local biodiversity in all its innocence.

We were photographing birds at a saline water body at Sippyghat in South Andaman, near Port Blair. Created by the tsunami, this water body is a great place to watch many birds, including the Andaman Teal (an endemic duck of the islands), Lesser Whistling Duck, Common Moorhen, Purple Swamphen, Stork-billed Kingfisher, Yellow Bittern, Cinnamon Bittern and a host of warblers. This place has also often thrown up surprises like Ferruginous Pochard, Eurasian Wigeon and Brown-headed Gull that are vagrants to the islands.

The evening seemed peaceful, with Common Moorhens preening, Andaman Teals (around 120 – in photo inset) resting in the middle of the pond and Yellow Bitterns waiting motionless for their next meal. Suddenly, there was some commotion at the far end of the pond and something white darted out onto an adjoining hillock. Evidently, a domestic cat. Training my camera on it, I realized that it was also carrying a quarry — a juvenile Common Moorhen had fallen prey to it. As it ran up the hill, the cat paused for a moment to adjust the position of the bird in its jaws and then disappeared into the undergrowth.

That day it was the Moorhen’s turn. Another day, it might have been an Andaman Teal’s turn. In the Andamans where there are practically no traditional terrestrial predators for birds (besides Water Monitors and Estuarine Crocodiles which can be termed as semi-terrestrial), domestic cats and dogs can have a big impact. These domestic animals are very common near modern human settlements, which are often on the fringes of wilderness and natural habitats.