It has been very good at Tyttenhanger Gravel Pits so far this year, with 137 species recorded up to 23 September, more than the full year totals for the years 2013-2016 with over three months of year still remaining. Highlights so far this year include Great White Egret, Caspian Gull, Little Gull, Hooded Crow, Bar-tailed Godwit, Iceland Gull, Garganey, Black Redstart, Temminck’s Stint, Avocet, Black Tern, Grey Plover, Tree Pipit and Redstart. 

The 137th species was rather special as Steve Blake, who birds the site most days and who found the bird explains…

‘I had spent all morning (Tuesday 12 September) searching hedgerows and other likely places hoping to find a Redstart to add to my year list. As I was walking the footpath along the river Colne, I caught the slightest glimpse of what I thought was possibly a Black Tern, or was it wishful thinking?

Being on the wrong side of the river, I hurried to the bridge that crosses to the fishing lake hoping to see the bird again. At first I could not find it so moved further down the lake. I soon located it, standing on the shingle bank on the far side. My immediate thought was BLACK TERN and took a very rushed hand held phone/scoped picture as a record shot, just in case it did what most migrants do at Tyttenhanger… fly off!

I knew Alan Gardiner and Terry Smith were on site so phoned them the news. By then the tern was in the air, bouncing around and dipping to the surface to feed. As I watched it, I gradually started to realise that it was different in plumage compared to the juvenile Black Terns I had seen at Wilstone a few days previously.

Could this be a White-winged Black Tern? …No, surely not – It can’t be – can it?

Alan and Terry arrived, and although none of us were familiar with the species, by searching images on my phone, we soon agreed, that this was a White-winged Black Tern!  I realised that because of the rarity of this species in Herts, some birders would immediately rush to see it, so it was most important to get the ID right, so a decent picture was needed before it flew off, as it was bound to do, they all do… don’t they?

Because the bird was so active, even with a very good camera and lens, Alan almost exhausted its memory card trying to obtain a few decent pictures, one of which I posted on Twitter and to my relief, confirmation was soon received. I posted an amended identification on Twitter and the bird news services. As expected, birders were soon on site (even leaving their places of work)!

This is a rare visitor to the county which has occurred on seven occasions involving a total of ten birds. All of the records have been from Tring, except one of two birds seen at Hilfield Park Reservoir. Last record was of two birds that passed through Wilstone Reservoir on the morning of 30 August 2008. (Birds of Hertfordshire). Rarer terns and gulls seen at Tyttenhanger usually fly through! So I was thankful that this one gave me the chance to reassess my initial identification, and that it stayed for six days, giving many people from both near and far a chance to see this ever confiding Tern.’ Steve Blake

Subject to rarity decisions, the White-winged Black Tern is the 203rd species to be recorded at Tyttenhanger. Visit the Tyttenhanger Site Guide to find out more about this excellent site and its varied habitats, including downloads of the annual Tyttenhanger Bird Reports.