The linked article below states that what he actually wrote was "I can assure you that all the bunnies here are of the woodland variety rather than jungle......."
He was therefore referring to bunnies of the jungle variety.
I suppose that if one wished to insult a coloured person then saying "Sir, you are a bunny of the jungle variety" is a bit more acceptable than saying "Hoi, you there, jungle bunny" but Bob Frost has not actually sought to deny that he meant jungle bunnies.
He later explained what he really meant on Facebook: "I have just had a phone call that accused me of racism for my above posting. Looking at the dictionary it would appear that the term jungle bunnies is perjorative [sic] and is a racist slur relating to African-Americans. Needless to say I did not mean to use any offensive racist term and was referring to the urban jungle." The councillor, who represents north Deal, added: "As for the bunny bit it was originally animals but I thought people might object to me calling fellow humans this so I chose something I thought was innocuous and also cuddly."
Clearly, as an academic, Bob Frost has led a sheltered life and was not to know that a bunny of the jungle variety was in fact a coloured person. The Urban Dictionary defines Jungle Bunny as "offensive term for a black man" and gives Thesaurus equivalents as "nigger coon porch monkey spook jigaboo black negro nigga spear chucker spade moon cricket darkie jiggaboo monkey niglet yard etc."
Have to say that I have never heard of most of these but I do remember the expression Jungle Bunny from donkeys years ago, particularly from New Zealand where Maori girls who liked a drink and were free with their favours used to reverse the initials and call themselves "BJ's."
http://www.dailymail.co.uk/news/article-2027390/Tory-councillor-Bob-Frost-suspended-racist-Facebook-jungle-bunnies-riots-remarks.html