A beluga whale has found itself in the Thames, dangerously close to London.
Members of the public have been asked to stay away as experts attempt to keep the sea mammal safe.
But conservationists fear that the animal might have got itself into danger after it has swum so far upstream. It is the first sighting of one of the animals – which tend to live in the Arctic – in years.
A huge container ship is making its way past the area that Benny is currently swimming around. Another reminder that nothing steps on this river, which is a central passageway into London and is host to some truly huge ships.
Discussion here on the riverside turns to Benny's fortunes. The RSPCA have said that it looks relatively well, and that it appears be finding food, so could be able to last quite happily for some time. But others on the bank point out that it is in awful long way from home, and that finding the way back up the river is going to be difficult. The dreadful memory of 2006 hangs over all of this, an awful reminder that whales "don't have the best track record", as one naturalist put it.
According to the RSPCA officials here, the whale will hopefully make its way back when it needs more salty water. That in turn should allow it to make its way home, all being well.
Here – that little white flash that you can hardly see – that's the whale. Look just to the right of the yellow buoy.
This small spot to the right of that barge is the important place – the whale is keeping to a very narrow area there, presumably feeding.
Just a little reminder that the whale still being here today is really a little unfortunate – conservationists had hoped that it would be making its way up the Thames and back into the sea by now.
"We are surprised and a little saddened that it has resurfaced again - we had hoped it had gone out to deeper waters and gone out to where it should be," said Lucy Babey, head of science and conservation at the ORCA charity.
"The most likely scenario, which we are not going to know until we can investigate this animal more, is that there is an impairment to its navigation system."
"If that navigation system is impaired or there is a lot of disturbance to its environment, whether from natural causes or man-made noise, the animal will not be able to navigate correctly and can go off course."
When you see Benny, it is only ever in the slightest flash. You'd easily be forgiven for mistaking it for the white crest of the little waves that occasionally break in the water.
Every four minutes or so, it makes its way up and out of the water. Then it'll do that a couple of times more. And then it'll head back down again, swimming until the next time.
On this part of the river – where people are being encouraged to watch – there's maybe 40 or 50 people. Most are animal lovers, waiting with long lens cameras and monoculars to catch sight of the whale. The rest are journalists.
And to put the challenge that awaits Benny into context, too – you can see on this picture some of the river that awaits on the journey eastward. Way off in the distance is the busyness of the London gateway, where ships are arriving and leaving all the time and which is a busy and fairly mucky part of the river.
Just to put that movement in context, it's gone from the barge you can see here on the left, to around the one you can see on the right – only a movement of 50 metres or so. But it's definitely in the right direction, and at least it's not in the wrong one!
Update from the RSPCA officers here on site : the whale is moving fairly quickly in the right direction (that is, east and back towards the sea, and away from London.)
Here’s the media scrum. (They’re actually quite a way from the whale now.)
Beluga whales aren’t the only wildlife out here - there’s horses, too. And plenty of dogs, whose owners are here to try and spot Benny.
It’s very much a working bit of the river that Benny has found himself in – he’s sharing it with huge ships that are continually making their way up and down the river.
ZSL, which runs the London Zoo among other important zoological projects, says that it is being kept up to date about the whale. "We're keeping our fingers crossed for a positive outcome," its Marine and Freshwater Conservation team tweeted.
The British Divers Marine Life Rescue has been monitoring the situation.
The network of volunteer "marine mammal medics" has whale rescue pontoons at the ready that can be used to refloat stranded animals in an effort to move them to safety.
A spokeswoman said the beluga's visit to the Thames was a "very rare occurrence", and urged people not to go out in boats to get a close look at the whale, but to watch it from the shore.
The overwhelming advice coming from experts is that the whale be allowed to do its thing – whatever that is. Authorities including the Met Police's Marine Police Unit have warned that the animal will need its distance so that it doesn't become distressed.
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