Keppel Island is completely bleached mainly due to the expansion of

Keppel Island is completely bleached mainly due to the expansion of

Starfish.
Blue whale.
Octopus.
Sea horse.
This question was previously asked in
UPSC NDA-1 – 2021
The correct answer is A) Starfish.
Coral bleaching is primarily caused by environmental stress, most notably elevated sea temperatures. However, biological factors can also contribute. Outbreaks of predatory starfish, specifically the Crown-of-Thorns starfish (*Acanthaster planci*), are known to cause significant damage to coral reefs by feeding on polyps. Severe predation can weaken the coral, making it more susceptible to bleaching, or cause direct mortality that appears as whitening (tissue loss revealing the white skeleton). Keppel Island, being part of the Great Barrier Reef ecosystem which experiences COTS outbreaks, is susceptible to such damage. While climate change and rising temperatures are the main driver of widespread bleaching events, localised stress from predators like starfish can exacerbate or cause bleaching in specific areas. Given the options, Starfish (Crown-of-Thorns) is the only organism listed that is a known significant predator of coral and contributes to coral damage and bleaching.
Blue whales, octopuses, and sea horses do not feed on coral and are not associated with causing coral bleaching. While other factors like pollution or disease can cause bleaching, the question points to “expansion” of a species, and Crown-of-Thorns starfish populations can undergo periodic outbreaks or expansions, leading to increased predation pressure on reefs.
Exit mobile version