OTTAWA - The Federal Court has rejected a native group's claim that recent changes to the census were unconstitutional.

The Native Council of Nova Scotia had asked the court to force the federal government to abandon plans to scrap the mandatory long-form census in favour of a voluntary survey.

The coalition of Maritime aboriginal groups argued the voluntary nature of the 2011 national household survey would produce skewed data about off-reserve populations, leaving them at a disadvantage.

The group's lawyer, Anne Smith, told the court that about 98 per cent of the long forms were filled out and returned in 2006, but only about 40 to 50 per cent of voluntary surveys are ever returned.

Smith said the voluntary survey will likely produce unreliable data from a smaller sample size, making it difficult for the government to discharge its constitutional duties to aboriginal peoples.

But Federal Court Judge Russel Zinn found the native groups failed to establish the existence of an aboriginal right that might be adversely affected by the changes.

Zinn wrote that the changes don't violate the charter of rights and would not hamper the government's ability to fulfil its duties under the Statistics Act.