Thames whale - as it happened: Beluga 'Benny' heads further upstream towards London as fears increase

If you’ve any questions, do please get in touch. The easiest way to do so is probably on Twitter, where I’m @_andrew_griffin.

Whoever it is ok that boat is having a good look at Benny — they’ve been out for quite some time now. But as before, you only get three or four glances every few minutes, so that might be required.

A police helicopter is circling right overhead, though presumably it’s not related.

You’ve seen a lot of the river and its bank, but here’s what it looks like on the other side. It’s a reminder that while we’re not far from London geographically, it’s a long way from the busyness of the capital.

If you're wondering how to get down to see Benny yourself, as Kath Francis just asked me on Twitter, you'll need to head to Gravesend. Specifically, you're going to want to come where the blue dot is here – which is actually quite a way from the centre of town.

Getting here is a little difficult. The best way is to head for the place that will show up on Google Maps as "Thameside Campus – National Maritime Centre". Follow the little road that takes you to, go down a little path where there's a sign for a footpath that has fallen down, and that should get you to the water's edge. Keep walking east, and you'll eventually get here. You can't miss it: there's a whole host of people waiting with cameras. They'll also help you out if you want to spot Benny – they've all got their lenses trained in the right direction and the whale is not moving around much.

(You can also see from the Essex side of the river, in Tilbury. But the view will be less good there and it's similarly hard to access.)

I just spoke with one whale watcher here who has made his way from Nottingham. He’s a committed whaler - but this is the first time he’s seen one in the water. It’s a reminder that spotting these animals is always tinged with sadness - if a whale is close enough to spot in the UK, something has probably gone wrong.

The tide has changed now, and the river is much higher. Benny is also moving up and down considerably more. Those two things are related, according to wildlife experts here on the shore.

Most of the people here are birders, as you can see from their substantial kit.

How long will they be staying? “Not long,” says one person here. “The problem is it doesn’t do much, once you’ve seen it. At least with birds they’ll fly off, or display.”

It’s hard to capture the scale of the boats that are going by here. But they are absolutely huge.