Marine wildlife experts say Benny the Beluga is feeding well and could be here for a long time.

Operations manager for British Divers Marine Life Rescue, Stephen Marsh has been monitoring the mammal since it was revealed it was in the River Thames.

He says he is surprised the whale is doing so well.

He added: "At the moment we still don't know if it is a male or female so it could be Benny or Belinda, but it is coping very well in the water.

"Beluga's are opportunistic feeders, which means they have a wide range of prey and if it couldn't find food it would keep moving until it does, but it hasn't moved yet, which means it must be feeding from a very good pantry that it has found.

"We don't know for sure what it is feeding on but it is likely that is sole, flounder and crustaceans."

Now that the weather is turning colder, Benny could become more adjusted to the estuary and stay there or he could get the call from the wild and travel back to the cooler waters.

Mr Marsh added: "Its a million dollar question about how long it will be here, as it gets colder it may go back to the north sea and hopefully turn left and head home.

"We don't know for sure where he has come from because there are lots of different types, Canadian, Russian, Norwegian etc."

Experts have said that they won't move Benny and whilst he is safe, will not intervene in getting him home.

Due to the extensive types of Beluga's, if he was to be moved to an area that was not his home, it would cause some problems.

Mr Marsh added: "If we were to drop him into any population that might be the wrong thing to do.

"For example we don't want to place a Russian whale into Canada, because they live completely differently and that could affect the diversity and it could take problems with it.

"We aren't able to move it at all, if he strands then it will be in our hands and we will decide what is best from there."

In order to keep an eye on Benny, divers have dropped hydrophone equipment into the water to listen to the sounds he is making.

So far, they have managed to get 15 minutes of sound, and it all indicates that he is happy and healthy.

The whale was first reported to be seen in the Thames in Gravesend back in September, but the first sighting was actually back in July in the River Medway.

Since then, Benny has been causing a bit of a stir amongst residents and has had a lot of visitors along the Promenade coming with cameras in the hope of snapping a picture of him.

Gravesham council have also postponed the annual fireworks display to keep him safe, with the hope of re-running it at a later date with a special Benny theme.

Mr Marsh said: "We were really concerned that the fireworks would shock the Beluga and we don't want it getting scared and swimming into London, so we are so pleased that the council have postponed the display.

"Throughout all of this we have been really happy and impressed with the reaction of the public, businesses and the council it really is great and we appreciate the efforts of everyone."

Councillor David Turner, Leader of Gravesham Borough Council, said: “Benny has become one of Gravesham’s attractions in his own right with many visitors coming to catch a glimpse of him and enjoying everything that Gravesend has to offer at the same time.

"It has been great to see the positive reaction to Benny, with everyone welcoming him. Many people have engaged with our #KeepBennySafe campaign with support coming from as far away as Australia.

“Keeping Benny safe remains our priority while he visits us here in Gravesend and we continue to liaise with The Port of London Authority and other agencies who are monitoring Benny and I’m pleased to hear he continues to be safe and well here in Gravesend.”