18th February 2019 - Coalhouse Fort, Essex

The second and last visit to Coalhouse Fort in February for the wintering bird surveys on the River Thames in Essex proved to be excellent. 

I started counting from the abandoned radar tower and received a text from Paul Hawkins to say he had just had a 2w Glaucous Gull over the BATA Factory. This had me on high alert but sadly it never reappeared. I then got another text saying that the 4 Twite found over the weekend were showing well near the bush on the sea wall which marks our survey boundary. 

The mudflats on a rising tide followed the norm and were rife with waders. Totals are as follows: 6 Bar-tailed Godwit, 560+ Black-tailed Godwit, c1500 Dunlin, 127 Grey Plover, 8 Curlew, 16 Redshank, 1314 Avocet and an Oystercatcher. As well as 46 Shelduck and 617 Teal.

Later in the day I managed to find the 4 Twite in the SSSI area. The birds were spending a lot of time on the large area of extensive salt marsh which runs alongside the Thames, whilst they are here they are near impossible to see. Occasionally they will fly into the SSSI area and feed on the new shoots from the bushes. I was rather lucky to see them just picking them up by chance whilst halfway round my survey. The second time I have seen Twite this year with the last being the 3 at Rye Harbour NR in East Sussex.

1 of 4 Twite, Coalhouse Fort, Essex (Courtesy of Paul Hawkins)

Other birds seen whilst visiting here included a healthy flock of 18 Corn Bunting and another 16 more in the SSSI area. 17 Lapwing were seen in flight coming off the rubbish dump. Around the car park was the usual Mistle Thrush and 7 Greenfinch. The moat around the fort was quieter than last visit just holding 7 Coots.

On the way home I quickly called into Mercer's Lake in Surrey to look for the juvenile Black-throated Diver. After some helpful advice on where to park from David, I managed to find the lake and the bird in no time and enjoyed fantastic views. It seemed quite active and dived quite frequently and luckily at one stage the it surfaced no more than 20m from where I was standing! Other birds seen whilst visiting here was a single Ring-necked Parakeet, 4 Great Crested Grebes, several Coots and Tufted Ducks as well as a Nuthatch. 

Juvenile Black-throated Diver, Mercer's Lake, Surrey