Six-year-old orca dies at Sea World San Diego

A six-year-old female orca has died unexpectedly at SeaWorld in San Diego after first showing signs of illness just one day before.

The orca, named Amaya, fell ill on August 18 and was treated by animal care specialists and veterans at the theme park immediately.

The next day she died suddenly and the cause of death remains unknown.

Specialists at SeaWorld are conducting a post-mortem exam to find out how the killer whale's health declined so quickly but said getting the results may take a couple of weeks.

Amaya - whose name means 'night rain' in Japanese - was the youngest orca at SeaWorld, where her mother Kalia and father Ulises still live. 

In 2014 SeaWorld San Diego announced plans to double the size of their killer whale tank - in a project dubbed the Blue World Project - in response to a wave of backlash they experienced after the release of the 2013 documentary Blackfish.

SeaWorld detailed plans to build 100million-gallon tanks that covered 1.5 acres and were 50 feet deep and 350 feet in length. 

The habitat was supposed to include stimulating features for the whales such as a foe fast water current. 

The original announcement said the facility was slated to open to the public four years later, with similar changes to be made at its Orlando and San Antonio locations to follow.

However, the new facility was never constructed and their tanks still only hold six million gallons of water for nine orcas.