HARI SREENIVASAN: You may have seen the documentary "Blackfish" that examined the treatment of killer whales at SeaWorld Orlando. Now at the Miami Seaquarium, another controversy is brewing over a whale named Lolita.

The National Oceanic and Atmospheric Administration is currently deciding whether Lolita should be placed on the Endangered Species list.

NAOMI ROSE: If she is listed as an endangered species, citizens will then have the right to sue on her behalf.

HARI SREENIVASAN: That could lead to Lolita being re-acclimated over time and eventually released back into the waters off Seattle, where she was captured in 1970.

Some scientists and activists argue that the tank where Lolita currently lives alone is too small for her well-being and that she should be set free.

Lolita has been dubbed "the world's loneliest orca." And this week, hundreds marched in Miami demanding her release.

But the Miami Seaquarium says it will fight any plan to put Lolita back into the wild, arguing that she simply can't survive on her own after 45 years in captivity.

Robert Rose, the curator of the aquarium notes how hard it is for an animal that's lived in captivity for so long to be returned to the open ocean.

ROBERT ROSE: I mean, she's gonna die, without question. They are going to take her out there and do exactly the same thing they did to Keiko which is to kill him.

HARI SREENIVASAN: Keiko was the iconic killer whale that starred in the movie "Free Willy".

Keiko was released into the waters off Norway in 2002 but died alone a year later of pneumonia.

ROBERT ROSE: Unfortunately this didn't have the Hollywood happy ending where Free Willy jumped over the wall and lives happily ever after.

HARI SREENIVASAN: NOAA's decision on Lolita's status is expected by the end of this month.