Royston Wildlife Blog: Local Wildlife Sightings, May 2023

My springtime posts have often featured news of the colony of Hairy-footed Flower Bees that co-existed with their cleptoparasite (Armed Melecta), in holes in a chalk bank at the side of a track at Hatchpen Farm. Well, the colony is no more. When I visited on the 3rd the track had been widened and the chalk bank lost, presumably as part of development works that have been going on for some time at the site. I guess that this is a classic example of why we are such a nature depleted nation - no doubt, the owners and developers were totally unaware of the colony and didn't give the bank a second thought. With more and more fields being concreted over as hundreds of new homes are built in the Royston area (who buys these homes?), countless other communities of 'insignificant' insects and other wildlife are being lost all around us, often without anybody being aware of it. Hopefully the bees that survived will find new homes, although I doubt it.

Brown Hare, Hatchpen Farm, Reed, 3 May

The weather in the first couple of weeks of May continued cool and unsettled, with the occasional warm, sunny day being followed by cooler weather again. Under these circumstances butterflies and other insects were predictably slow to emerge and it was only on the 15th, in drier and slightly warmer (16C) weather, that I saw my first Brown Argus butterflies on Church Hill. During the following week numbers of Brown Argus increased to an impressive 40+ in quite a small area. The first Common Blues appeared on the 18th when, for the first time this year, the temperature rose to 20C on The Heath. Adonis Blues were seen for the first time on Church Hill on the 22nd, as an area of high pressure built over the UK giving rise to warm, dry and often sunny weather. Spring had finally arrived, and with it out came my macro lens. Brown Argus butterflies, which were now present at both ends of The Heath in big numbers, proved to be excellent subjects: a couple of images are shown below. By the 24th Adonis Blues had emerged on the Old Rifle Range. Other species seen locally for the first time in the second half of May included Holly Blue (one seen in the garden), Small Tortoiseshell, Speckled Wood, Large White, Red Admiral and Small Heath.

Mating Brown Argus Butterflies, Therfield Heath (Church Hill), 18 May

Brown Argus Resting on Snail in Evening Light, Church Hill, 24 May

Male Common Blue Butterfly, Therfield Heath (Church Hill), 18 May

I had to admit defeat in my search for local passage migrants (in particular Wheatear and Ring Ouzel) by the end of the first week of May - the first time that I have failed to see at least one of these species in the spring. However, I was lucky that, on Coronation Day (6 May and a very rare Saturday spent at home) a Whimbrel and a Dotterel were both found (Mike Ilett) in a field north of Ashwell, so I was able to see (in pouring rain) both species - rare passage migrants in Hertfordshire. The Dotterel (a drab male) was too distant to photograph, but I managed to get a distant 'record shot' of the Whimbrel (below).

'Record Shot' of a Whimbrel, near Ashwell, 6 May

I was away on holiday from the 7th to the 14th. Although Swifts had been reported from Royston whilst I was away, I had to wait until the 18th before seeing a couple over Royston town centre. Sightings became more frequent towards the end of the month, during the settled period of sometimes warm weather (but with a more or less continuous cool, easterly or north-easterly breeze), but it is puzzling that they are taking longer and longer to arrive here - until recently, swifts would always return to Royston around 6 May! Last year they were a week late. Have they been affected by the cold, damp weather here, or held up by the storms in the Mediterranean region? I saw plenty in Yorkshire and Northumberland whilst on holiday, so their late arrival is a bit of a mystery. House Martins were seen over The Heath on the 16th, although as far as I know they no longer nest in Royston. However, I was delighted to find at least two (possibly three) Spotted Flycatchers back in Fox Covert on the 18th. After a barren year in 2022 I hope that they will nest successfully here in 2023. A Quail was singing in a 'weedy field' just off The Heath on the 24th. Although Quails are rare summer visitors nationally, one or two often turn up in the Royston area and this is the second year that I have heard one less than a mile from my house.

My interest in local birds waned towards the end of the month (as it usually does) and I concentrated once more on insect photography. One species of fly that was very common (even abundant) close to the house was (I think) the Dance Fly (Empis tessellata), with individuals bouncing up and down close to flowering Hawthorn bushes and even Cow Parsley (which, despite its abundance, attracts very few insects). This large fly appears innocent enough, but I did photograph one which had caught a cranefly - these insects are predatory!

Dance Fly with Crane Fly Prey, Royston, 17 May

Although the weather remained settled, the last few days of May saw very little sun and, with a cold wind coming from the east, insect activity dropped away again. Adonis and Common Blue numbers on Church Hill remained low (worryingly, I only saw a single female of each species there during May and early June), although numbers were higher on the shorter grass of the Old Rifle Range. Local Odonata seen during the second half of the month included a Large Red Damselfly (seen a few metres from the house) and a Broad-bodied Chaser dragonfly. Hoverfly numbers were much lower than usual, although I did see quite a few Bee Hoverflies, Volucella bombylans.

Bee Hoverfly, Volucella Bombylans

Hoverfly, Xanthogramma Pedissequum

Some interesting observations were made of birds feeding in the garden during May. Whereas Jackdaws and Magpies are the main beneficiaries of the various types of suet that I provide, I did notice a couple of Carrion Crows in the garden. These very intelligent birds soon became adept at tipping one of the feeders upside down, so that the suet cake within fell out and they could consume it at leisure. This happened a couple of times - in the end I decided to leave the feeder empty. A Song Thrush was a very rare visitor to the garden on the 5th. Whilst I would have appreciated it removing some of my many snails, it seemed more interested in the rather more useful (to gardeners) worms. Finally, on the 31st, I was delighted to see a family group of Greenfinches (at least five, including three adults) on the sunflower heart feeders and in the bushes. However, there was a sad postscript when, a few days later, I found one juvenile dead on the patio, presumably having flown into a window or door.