The company that operates the Ranger uranium mine in the Northern Territory has reported a $154 million loss for last year.

Energy Resources of Australia Limited (ERA) says processing operations and mining activities have been affected by extreme weather in the Northern Territory.

Mining at Ranger shut down in January last year after torrential rains caused flooding and it did not re-open until June.

The company recorded a $47 million profit in 2010.

ERA is 68.4 per cent owned by mining giant Rio Tinto.

In early trading on the Australian Stock Exchange today, ERA shares were trading at about $1.42, down more than seven per cent on the previous day's closing price.

About 18 months ago, ERA shares were trading at close to $14.

Six months ago, they had fallen to about the $4 mark.

The Ranger uranium mine is located near Jabiru, within the boundaries of the Kakadu National Park.