Drought conditions continued into August, with daytime temperatures varying a few degrees either side of 28C and no sign of rain. Locally, many crops had already been harvested by the end of July - ripe, but with lower than average yields. The Heath was slowly turning from brown to yellow, with hardly any flowers and, consequently, very few insects other than the ubiquitous but declining Chalkhill Blue butterflies, most of which were looking decidedly tatty, and second generation Meadow Brown, Common Blue and Small Heath butterflies. I say 'second generation' Meadow Brown advisedly, because there is really only one generation, but I have noted more than once that there seem to be two emergences, one in June and one in late July, with a gap in between. Also, more of the larger form (females?) are seen in the second emergence. With the exception of the ubiquitous Jersey Tiger Moths, which regularly popped out of nearby vegetation when I was gardening, and a host of smallish grasshoppers, very few other insects were seen on or near The Heath. Hoverflies, in particular, seemed to be doing very badly in the drought, although the largest species, the Hornet Hoverfly (Volucella zonaria) was seen regularly.
Hornet Hoverfly, Volucella zonaria, Royston, 1 August
Local dragonfly numbers were well down on recent years, probably at least partly due to ponds drying up and a shortage of insect prey. A few Migrant Hawkers were seen on and around The Heath and a beautiful male Emperor Dragonfly posed briefly for me when I visited Phillup's Lake on the 6th.
Male Emperor Dragonfly, Phillup's Lake, Reed End, 6 August
Little Grebes (adults and juveniles) were still present on Phillup's Lake, as were a host of moulting Mallard ducks and a single moulting Tufted Duck. An adult and juvenile duck, which I had assumed were Mallards and did not bother to photograph, turned up very blurred on one of my photographs of the Tufted Duck and may have actually been Gadwall - I will have to return to check this out, as breeding Gadwall on the lake would be a local 'first'. I assumed that another photo, of another small bird that was seen to dive at the far side of the lake, would be of a Little Grebe. However, the bill of this bird was far too broad. Having ruled out the possibility of an extreme rarity (juvenile Pied-billed Grebe, an American species) on common sense grounds, I came to the far more logical conclusion that this was in fact a juvenile Coot (Coot do dive and, as readers of this blog know, they do breed on Phillup's Lake). Anyway, the image is below.
Juvenile Coot (I assume), Phillup's Lake, 6 August
Having seen a report (Rupert Evershed) of Caspian and Yellow-legged Gulls at Tyttenhanger Gravel Pits, I visited on the evening of the 5th. Water levels were very low, but I managed a few shots of large gulls both on the exposed mud and on the lake itself. One of the paler mantled gulls (not Lesser Black-backed) on the mud had yellow legs (so, I assume Yellow-legged Gull) whilst a number of juveniles on the water appeared to be Yellow-legged or Caspian Gulls. The image below shows some of the gulls - what a motley selection!
Some of the Gulls on the main Lake at Tyttenhanger Gravel Pits, 5 August
I took a photograph of a Small Heath butterfly whilst visiting the Henry Moore Foundation at Perry Green (near Bishops Stortford) with my partner on the 9th. Although it is a small, brown butterfly on a brownish background, I quite like the photo and may get a print of it in the future.
Small Heath Butterfly on Grass Stem, Perry Green, 9 August
I had been waiting for a couple of weeks for the emergence of the second generation of Adonis Blues on The Heath and finally, on the afternoon of the 10th, they appeared - and in good numbers - on the Eastern Heath (between Lankester Hill and the Sporting Clubhouse). I saw perhaps 30 - 40 males and one or two pristine females (although these could have been late emerging Chalkhill Blue females - the females of these two species are hard to separate). Also seen were good numbers of Meadow Brown, Small White and Small Heath butterflies, a few Common Blues and Brown Argus and a single Clouded Yellow, which refused to settle and allow me to take its photograph (this has been the best year for migrant Clouded Yellow and Painted Lady butterflies since 2009).
Male Adonis Blue Butterfly, Therfield Heath, 10 August
Male Adonis Blue Butterfly, Therfield Heath, 10 August
On the way home, I passed a field that was being ploughed and saw my first big local gathering of gulls (the vast majority Lesser Black-backed, with a few Common and Black-headed Gulls) of the autumn. Also present were seven Red Kites and a large number of corvids, making the most of a rare opportunity to look for large invertebrates beneath the parched ground. I was hoping to see my first local Caspian Gull (there had been a big influx into the country in the previous few days). One possibly interesting gull did turn up, an immature bird with long wings and tail that made it look like a small vulture, but my photos, looking in to the sun, did not pick up enough detail for me to try to identify it. It's on the right of the image below.
Gulls 'following the Plough', Royston, 10 August, with mystery gull on the right. The remaining gulls are all Lesser Black-backed: the gull second from the left looks paler due to a trick of the light.
Gulls (and a Jackdaw) with mystery bird second from the right, Royston, 10 August
From the 11th we braced ourselves for another heatwave (the 5th of the year), and the 13th turned out to be the hottest of many hot days this summer, with the temperature in Kew Gardens reaching 38.2C. For once, I heeded instructions to keep indoors!
