Milletseed Butterflyfish feeding on eggs of Sergeant Major Damselfish_02

Milletseed Butterflyfish, aka Lauwiliwili, are endemic to Hawai‘i, which means they occur nowhere else on Earth.
The Hawaiian Sergeant Major, aka Mamo, is also endemic to the islands and found nowhere else in the world. 
Hawaiian Sergeant Major eggs are a significant food source on the reef. Milletseed Butterflyfish are notorious egg eaters on the reef, forming a 'trophic mob' to feed on the ova (eggs) of nesting damselfish. Once a Milletseed attack has begun, wrasse, other butterflyfish and damselfish join in, creating a colorful feeding frenzy.
Like a soldier on guard duty, the male Hawaiian Sergeant Major earns its stripes through patrolling and defending its nest until the eggs hatch, being vulnerable to predation as it nests on vertical surfaces, boulders, ledges, and flat open areas within the reef. 
 
Milletseed Butterflyfish
Scientific Name: Chaetodon miliaris
 
Hawaiian Sergeant Major Damselfish
Scientific Name: Abudefduf abdominalis