Oct 16th-20th: Fog and migrants

I started the second half of October with a morning at Brent Res, hoping for some visible migration but, like so much of this month, it was fairly quiet with just a flock of four Little Egrets flying over being unusual. The Stonechat remained in situ on the Dump and it was still present the following day as well, making it four days. Typically, Stonechats don’t linger at Brent so it was nice to get one that found the place to its liking.

After a short vis-mig session on Monday morning where the only bird of note was a high flying Snipe, I headed over to Fryent CP to try my luck over there. It’s only a short walk from the playing fields at the top end of Brent so I was there early enough to continue vis-migging. A few Linnets and a Siskin flew over which were both new for the year here, otherwise there wasn’t much activity.

With easterlies predicted for the next couple of days I decided to concentrate my time on Rainham. I took an early train on Tuesday and things looked fine until we reached Dagenham and the landscape disappeared under a dense shroud of fog. I didn’t see that on the weather forecast but should have realised with the drop in temperature, high pressure and lack of wind making the ideal conditions.

I still hoped that the fog may have downed some migrants so was on full alert as I walked through Rainham West but there was very little moving. The Cetti’s Warblers remained silent in the ghostly conditions and with low visibility it felt like walking through a post-apocalyptic film set.

A pylon appears out of the fog

Traps set optimistically along a bridge for a Troll

Entrance to the old silt lagoons, now being covered in chalk

A spider's web glistening in the foggy dew

I took the shorter path along Coldharbour Lane and went straight past Serin Mound as Wennington Marsh was invisible in the gloom. Along the river wall it was only possible to see anything on the close mud with the river and far bank totally obscured. Out in the distance I could hear a fog horn and it reminded me of the young Pip in Great Expectations. One day I might get around to reading another book by Dickens!

I lingered on the river wall and eventually the fog began to dissipate, typically clearing and then reforming at first so Crayford Marsh appeared then vanished again. A few more waders emerged out of the fog and there was a Ruff and the long-staying Grey Plover on the mud along with a little gaggle of Avocets. That’s probably the wrong collective term but I’m struggling to come up with anything better. A little group of Reed Buntings were feeding on some fallen reeds on the concrete apron.

Reed Bunting

A solitary Avocet emerges from the fog

As I looked over towards the reserve I noticed a ghostly apparition forming – a White Rainbow. It wasn’t a phenomenon I’d seen or even heard of before but it was quite stunning. I looked it up online later and it is actually a thing, also called a Fogbow and occurs in the same way a rainbow is formed but the fog particles reflect the light so that the colours aren’t produced.

A Fogbow or White Rainbow over the river wall

With the fog receding I headed into the reserve and made my way clockwise to Butts Hide, seeing a pair of amorous Migrant Hawkers along the way.

Pair of Migrant Hawkers

There was another Ruff out the front of the hide but very little else so I didn’t go round any further. As I headed back a Buzzard soared around near the numbers.

Common Buzzard

The next day I was back again, this time starting at Purfleet station as the forecast was for a moderate easterly and I was hopeful of some seabirds coming up the river. I parked myself on a bench in front of the closed hotel and waited. Redwings were constantly calling and a few small flocks zipped past. A little while later an unseen Brambling wheezed past and it seemed like the conditions were ideal for a decent vis-mig session. Not long after I hit the jackpot when I heard a light trill overhead and looked up to see the culprit struggle to make it across the river. With its short tail it looked more like a bat than a lark, a dead giveaway for Woodlark. I’ve seen a couple migrating over Brent and one at Swanscombe but this was my first one in the Rainham area.

Woodpigeons were also on the move and they too struggled to get across the river, with one group abandoning their first attempt before circling around and trying again. I was still watching the river although nothing was coming from the east. A few Wigeon flew around and then I spotted a couple of terns on the far side. I switched to the scope and could see they were Sandwich Terns heading downriver.

With migration quietening down I headed along the river wall and had a look at Aveley Bay but there wasn’t much happening there so I went into the reserve and this time went round to Ken Barrett hide. The water level had gone up since my last visit and there were only a few Snipe remaining and very little else. In the distance I could see Marsh Harriers out hunting and after a while counted three different birds, a pair of adults and a young male.

I decided to walk on to Rainham station in case a Ring Ouzel had dropped in but to no avail. It did give me the opportunity to investigate the stone numbers which I’d always walked past but intrigued me. Luckily a sign explained their purpose. I didn’t find any for 500 and 600 so not sure if they’re on another path or don’t exist.

I also learned something else as I assumed that Portland stone came from the quarries on Portland Bill but apparently it also comes from the Isle of Wight.