The number of registered voters in Scotland has dropped by more than 145,000 from the high point reached just before the independence referendum, it has been revealed.

In March this year there were 4,138,345 people north of the border listed on the electoral register, the Electoral Commission said.

That is a drop of 3.4% - or 145,593 registrations - from the high point of 4,283,938 achieved in September 2014 in the run-up to the vote on Scotland's place in the UK.

Even when 16 and 17 year olds - who were allowed to vote in the referendum but do not have a ballot in May's general election - are excluded, the total is still down by 1.8%.

That means the number of people aged 18 and over who are registered to vote was 76,592 less in March than it had been in September.

The Electoral Commission report said that the position last September "represented a high point against which any subsequent registers were more likely to decrease than increase".

It added: "The lack of comprehensive household canvass activity since the end of the 2013 canvass is likely to be a key reason for this fall."

But the number of registered voters in Scotland is higher than it was in March 2013, having increased by 0.4%.

The report said this slight increase compared to a "decrease of approximately 2% in England and Wales where the December 2014 registers contained approximately 920,000 fewer entries than the registers published in February/March 2014".

Electoral Commissioner for Scotland John McCormick said: "The registers published on March 2 2015 are a snapshot of the electorate at that time and work is continuing to get as many people as possible registered in time for the May election.

"There is still time to register before the April 20 deadline and we would urge anyone who is not registered to take action now by going to www.gov.uk/register-to-vote. It's easy and only takes a few minutes."