I don't know what they're feeding them on north of the border, but thats one big fox.
http://www.bbc.co.uk/news/uk-scotland-north-east-orkney-shetland-17259087
http://www.bbc.co.uk/news/uk-scotland-north-east-orkney-shetland-17259087
recent article in Sporting Shooter magazine reported a similar sized specimen, and gave one possible reason for increasing size being the decline in professional estate wardens / games-keepers (who were only ever really interested in confirming the kill) and the corresponding rise in pest-control being done by sporting shooters (who are more likely to record & share the size etc) - seems pretty plausible to me, as i know most of my local farmers would just sling it in a hedge...
definitely not an urban fox
Why not? Aren't they the same species?
You might want to check where Rothiemay is.
Red foxes in the Scottish Highlands do tend to be significantly bigger, with thicker coats and bushier tails than elsewhere in Britain. No one seems to know why. Still a very big fox though, but definitely not an urban fox as the expert from the GWCT seems to think.