Local Wildlife Sightings, August 2025

 After a changeable first week, in which there was some (but not enough) rain, the weather settled into another spell of very warm or hot weather, with the fourth 'heatwave' of the year arriving from the 11th - at least in the Royston area. On Therfield Heath, Chalkhill Blue numbers peaked at the beginning of the month, before a gradual (or rapid, in the case of Gatekeepers) decline of these and most other species set in. The exceptions were Small Heath, with the appearance of another generation, and Adonis Blues, first reported at the end of July, which were present at both ends of The Heath by the 9th. There was a welcome increase in numbers of these in the second week of August, with a few males being seen away from the colonies on the Old Rifle Range and Church Hill. There has been a small influx of Clouded Yellows from Europe this month. Some were reported on The Heath on the 10th and a single butterfly flew north past me, on the Old Rifle Range, on the 11th.

Male Adonis Blue, Therfield Heath, 11 August

Female Common Blues with varying amounts of blue on the upper wings were seen in the fields near my house. I tried to photograph them all, but unfortunately missed out on the most spectacular one, with wings almost completely covered in a shade of violet. I did a little more photography of blues roosting in the evening light, but by the end of the first week of the month they were becoming increasingly tatty.

Male Common Blue (left) and Chalkhill Blue, Therfield Heath, 7 August

Blue Variant of a Female Common Blue, Royston, 8 August

Whilst butterflies have had a much better year, I have seen very few day flying moths on The Heath or night flying moths coming in to the bathroom this year. Maybe they have been hit harder by last year's poor weather. I can't remember seeing any 'Silver Y' moths (normally the commonest day flying moth hereabouts) at all, although other factors may be at work here, as this species is migratory. Two moths that I have seen regularly are Hummingbird Hawkmoth (one even got into my greenhouse - not too difficult as it has one or two broken panes of glass) and Jersey Tiger Moth, which goes from strength to strength, having only arrived in the Royston area a few years ago.

I start spending more time looking up (for birds) rather than looking down (for insects) in August. Waders are migrating across the country in August and Dernford Farm Reservoir, just across the border in Cambridgeshire, has plenty of mud available for them in the current near drought conditions. I visited on the 11th, looking for Ruddy Shelducks that had been reported there on the previous day. There was no sign of the Shelducks, but I did see six Black-tailed Godwits and a juvenile Spotted Redshank on the mud there. A male Ferruginous Duck (unfortunately an 'escape', so I can't list it) was also present (image)

Male Ferruginous Duck, Dernford Farm Reservoir, 11 August

Spotted Redshank, Dernford Farm Reservoir, 11 August

Closer to home, I flushed three Grey Partridges on The Heath on the 14th. One was much smaller than the others: it must have been a juvenile as juvenile game birds learn to fly well before they are full grown, in order to escape their many ground (and avian?) predators.

High pressure continued to dominate the weather in the third week of August, but, with the wind coming from the north and east, Royston was plagued with lots of low cloud and much cooler temperatures. Insects became much less active under the cloud, although I was lucky to be out on Church Hill when the sun came out for an hour or so in the late afternoon of the 19th, and I was able to photograph male and female Adonis Blues there, as well as a Hummingbird Hawkmoth that seems to have been present in Fox Covert for several weeks. The best photo that I could manage of the hawkmoth is shown below. Around 20-25 Adonis Blues were flying on Church Hill, including 'fresh' females. It may not be true elsewhere, but in this colony many of the females have some blue markings on their backs and upper wings (see example below), which I don't see on the otherwise very similar Chalk Hill Blue females. In addition, the spots on the lower wings are bolder than those on female Chalk Hill Blues. After a very poor 2024, it is good to see numbers of Adonis Blues recovering this summer, even though numbers are still well below where they were in the years after they had first been introduced.

Female Adonis Blue, Church Hill, 19 August. Note the Blue Efflorescence on the Body and Wings

Male Adonis Blue, Church Hill, 19 August

Record Shot of Hummingbird Hawkmoth, Fox Covert, 19 August

The dry weather has resulted in the water levels in lakes and reservoirs falling, resulting in lots of muddy margins - ideal for waders on passage. During the duller days I visited Amwell, the Tring Reservoirs, Dernford Farm Reservoir (which, by the time I visited on the 21st, was almost dry) and Kings Meads, where a juvenile Spotted Redshank had been discovered a couple of days beforehand. Other waders seen at these sites were Ruff (four at Dernford Farm Reservoir on the 21st), Green Sandpipers, Common Sandpipers (lots) and a Common Redshank. At Wilstone Reservoir, where there is very limited access due to long term engineering works, a couple of Hobbies flew over and at Startops End a colourful Mallard (?) hybrid and a Black Swan were seen. Lots of hirundines, including my first (!) Hertfordshire Sand Martin of the year were flying over the water here.

Green Sandpiper, Kings Meads (Between Hertford and Ware), 21 August

Juvenile Spotted Redshank, Kings Meads, 21 August

Hobby over Wilstone Reservoir, 20 August

Mallard (?) Hybrid, Startops End Reservoir, 20 August

Local Wildlife Sightings, July 2025

 Back from holiday early on the 3rd and with an enormous amount of sleep to catch up on, I nevertheless managed a short evening walk on the same day along the Greenwich Meridian Trail, south of Royston, where I knew that I would find hundreds of Essex Skippers. Most had clearly been on the wing for a few days and were looking rather ragged, but I did manage to get a few photos of decent specimens in what is a very large colony. As expected, Chalk Hill Blues and Gatekeepers had emerged (the first Chalk Hills were reported on the 25th of June, the day I left the UK). Marbled Whites were still flying on The Heath when I visited on the 4th. Chalk Hill Blues were seen in relatively small numbers, but very large numbers of Gatekeepers were seen. The first of the second generation of Brown Argus were already on the wing, very early but in line with other butterfly species that have emerged early in what promises to be a long, hot summer.

Essex Skipper, Royston, 3 July

Brown Argus, Therfield Heath, 4 July

Male Chalk Hill Blue and Hoverfly on Knapweed, Therfield Heath, 4 July

A visit to Phillup's Lake on the 7th was rewarded by seeing families of four Little Grebes and three Coots. A handful of moulting Mallards and a single female Tufted Duck were also present. Nearby, I saw my first local Small Copper butterfly of the year, as well as an Emperor Dragonfly and several Common Blue Damselflies. As I reached three score years and ten, two more birthday related holidays kept me (happily) away from my local patch, so sightings were very sporadic until the 20th. However, I did manage visits to The Heath (Old Rifle range area) on the 12th, where I saw my first local Small Copper of the year, and Hertford Heath, where I saw Purple Hairstreaks flitting around in various Oak trees. The ponds had almost completely dried up and dragonflies were scarce here.

Female Chalk Hill Blue, Therfield Heath, 12 July

Small Copper, Therfield Heath, 12 July

On a visit to Fox Covert on the 14th I was very pleased to encounter an admittedly rather battered male Silver-washed Fritillary, the first that I have seen here since 2023. This species, which only arrived in the woodland a few years ago, is struggling to survive here in habitat that is not ideal, but will likely have bred here in 2024 (or maybe this male arrived from another colony this year?). Also seen in the woods were single Common and Ruddy Darters, the latter having a split and twisted abdomen, perhaps caused on emergence from the chrysalis.

Ruddy Darter with Damaged Abdomen, Fox Covert, 14 July

Record Shot of a rather battered male Silver-washed Fritillary, Fox Covert, 14 July

Following another holiday (see my UK blog) I was finally home for more than a couple of days from the 20th. The weather had finally deteriorated into what for many years was a typical English summer (thunderstorms, showers and longer periods of rain, average temperatures) and there was plenty to catch up on at home, but I did manage a few visits to local sites and, strangely, had my best week of the summer for local wildlife photography. Several female Chalk Hill Blues were now on the wing, and I photographed four mating pairs during the following week, including two pairs that were almost side by side at the bottom of Church Hill. Common Blues were also seen mating, whilst the dominant species on the wing, certainly on The Heath, was still Gatekeeper. On the 21st I led a Royston Photographic Society wildlife photography session on The Heath, near the Therfield Road, where in addition to lots of Chalk Hill Blues being seen, we found mating Burnet Moths and a large, female Wasp Spider!

Mating Chalk Hill Blue Butterflies, Therfield Heath, 22 July

Mating Common Blue Butterflies, Royston, 21 July

Mating 6-Spot Burnet Moths, Therfield Heath, 21 July

Female Wasp Spider, Therfield Heath, 21 July

Two Roosting Male Chalk Hill Blues, Therfield Heath, 22 July

Lizard Orchids

Back in the middle of June, two Lizard Orchid plants were found just off the Old Rifle Range (Nick Keep). This is, as far as I am aware, the first time that this species of orchid has ever been seen on Therfield Heath, although it is possible that they may have been here before without anybody noticing. I was asked not to publicise their appearance, as they are an uncommon plant and there was a risk of them being (unwittingly or maliciously) damaged. However, I did take some photos of the plants (one appears in the August issue of 'The Listing', where some of my butterfly photographs can also be seen), a couple of which are shown below. Lizard Orchids are particularly large orchids, which don't (in my eyes) look particularly attractive. However, they are a great addition to the flora of The Heath - I wonder whether any will appear next year? At the time of writing (30 July) the plants can still be seen, although they are wilting and decaying.

The two Lizard Orchids, Therfield Heath, 17 June

Detail of the flowers of one Lizard Orchid, Therfield Heath, 17 June

During the final week of July I concentrated, when I could, on photographing (mainly) roosting Chalk Hill and Common Blues, both on The Heath (Old Rifle Range) and at Clothall Common near Baldock, where the colony is doing well (I estimate that 200 - 250 individuals were roosting there when I visited on the 30th). I was hoping to find some aberrant individuals, but it seems that nowadays all Chalk Hill Blues look the same (well, obviously males and females differ and their colour changes with age). Here are a few more images. Incidentally, I have been asked to spell 'Chalk Hill' as two words, rather than the one 'Chalkhill' word that is in my butterfly identification books - don't ask me why!

Male Chalk Hill Blue, Therfield Heath, 29 July

Male Chalk Hill Blue resting on Scabious Flower, Therfield Heath, 29 July

Two Female Chalk Hill Blues, Therfield Heath, 29 July

Two Male Chalk Hill Blues, Therfield Heath, 29 July

Towards the end of the month, a number of pristine looking Painted Lady butterflies were seen in the Royston area. These would be the offspring of butterflies that flew across from the Continent in the late spring. Some were seen feeding voraciously on a variety of nectar, preparing themselves for the long journey back to Southern Europe, which they undertake in the late summer and early autumn.

Painted Lady, Royston, 31 July

Swift Survey

Every year I carry out an unofficial survey of the swifts in Royston town centre. The best time to do this is in late July, when the young birds have fledged but before the birds begin their migration back to Africa in early August. The best (only?) time of day to carry out the survey is in the 40 minutes or so before dusk, when the birds descend and form 'screaming parties' over the town, so I have to work quickly! I can only get a very approximate figure, because the birds are flying around rapidly, in groups of up to 15 which can splinter and re-form. However, they do tend to stay close to their breeding sites which makes my job somewhat easier. This year my rough estimate was of 85 birds, similar to last year. I report my findings to the BTO ('Birdtrack'). I have to say that I really enjoy seeing Swifts flying around like this - they appear to be so happy! I hope that they will return in good numbers next year.

Local Wildlife Sightings June 2025

 After an impressively warm and sunny spring, it was back to changeable weather in June with a few warm, sunny days interspersed with showers and longer periods of rain. I took the opportunity on the 2nd (a warm, sunny day) to visit local fields and Therfield Heath, looking mainly for butterflies. Numbers of first generation Common Blues and Brown Argus butterflies were falling now on The Heath, whilst I failed to find any Adonis Blues there. However, on the small wild flower patch in the field that is behind our estate, which has proved quite productive in the past, I was lucky to find a recently emerged male Common Blue, which flew conveniently towards me and perched on top of a flower bud, allowing me to take some nice photos. If only all insects were so obliging!

Male Common Blue Butterfly, Royston, 2 June

After changeable weather in the first week, high pressure built again with plenty of sunshine and temperatures building to a climax between the 18th and the 21st, with an official heatwave and a maximum temperature in Royston of 31C (or possibly higher - I'm relying on the temperature gauge in the car!). It has been a disappointing spring migration period locally for birds, with no sign of Wheatear, Garden, Sedge or Reed Warblers. Spotted Flycatchers were not encountered in Fox Covert during the month, although to be fair I didn't spend much time looking for them. There was some joy, however, on two late evening owl walks. On the 12th a Barn Owl crossed the GMT trail in front of me, heading SE from Flint Hall Farm towards and then beyond Half Moon Plantation, less than half a mile from the house. Further down the track two Tawny Owl chicks (one seen) were squeaking away. There were no Barn Owl sightings on the 18th, but the two Tawny Owl chicks were still present and I also saw a Badger, a Fox and a few bats. Unfortunately there was no sign of Little Owl activity on either walk.

It was necessary to be out early or late to find much bird activity on the hot days. Chiffchaffs, Blackcaps, Whitethroats and Lesser Whitethroats were all singing again in the second half of the month (well, the Chiffchaffs never really stopped) and were presumably having successful breeding seasons, the first juvenile Goldfinches appeared at my feeders early in the month and juvenile Blackbirds, Great Tits and Blue Tits were also seen in the garden. All four resident species of pigeon and dove were seen in the garden, both hoovering up spilt bird seeds and drinking from the terrace pond. Jackdaws and many species of small bird were also using the garden ponds to drink from. On The Heath, another Grey Partridge was seen on the 16th.

Grey Partridge, Therfield Heath (Old Rifle Range), 16 June

Some butterfly first sightings were, at least for my own records, very early. Dark Green Fritillaries were seen on The Heath from the 6th, both Small Skipper and White-letter Hairstreak from the 16th (with specimens of the last being seen at the bottom of my road on the 19th). Only Large Skippers, which only appeared in any numbers from the middle of the month, bucked the trend by appearing at the 'right time'. Common Blues kept appearing in ones and twos throughout the month, but I saw no Adonis Blues after the 4th, although they were reported later by others. Small Tortoiseshell Butterflies seem to be slowly recovering after some disastrous recent years: I saw six together near my house on the 10th and another four on a walk between Wallington and Clothall Common. Painted Lady butterflies have also been seen in greater numbers than in the last couple of years, but the biggest butterfly surprise this year to date was to see a Clouded Yellow in pristine condition on the 16th, which put in a brief appearance (too brief to get a photo) on my local wildflower meadow before flying off strongly to the west. I presume that this specimen had hatched recently in the UK, from eggs deposited by an early continental migrant.

Dark Green Fritillary (Side View!), TH, 6 June

Large Skipper, Royston, 16 June

Small Skipper, Royston, 16 June

Small Tortoiseshell, Royston, 10 June

Ringlets appeared from the 16th and were quite numerous when I visited Fox Covert and Jubilee Wood on the 25th. Essex Skippers were seen locally from the 24th. A visit to Scales Park on the 24th provided a brief glimpse of a Silver-washed Fritillary, but no sign of Purple Emperors (reported on the 22nd) - I'll try again later. Huge numbers of Marbled Whites were on Church Hill on the 25th, having switched their favoured plants for taking nectar from Privet (nearly finished) to the large clumps of Knapweed and Field Scabious flowers. At least four Dark Green Fritillaries were seen here (image to follow), with many more at the east end of The Heath, but there was no sign here of Silver-washed Fritillaries, which I haven't seen on The Heath since 2023. A White Admiral was seen when I visited Balls Wood nature reserve (Hertford Heath) on the 18th.

Essex Skipper, Royston, 24 June

Other invertebrates seen in June included Hummingbird Hawkmoth (one was feeding on my Valerian on the 16th), Summer Chafer and a new (for me) longhorn beetle, Golden-bloomed Grey Longhorn Beetle, seen near to the house. A (presumably Jersey) tiger beetle was seen in flight. A visit to Clothall Common on the 20th yielded no 'blue' butterflies, but surprisingly large numbers of six-spotted Burnet Moths were seen, considering that I hadn't seen any elsewhere on my travels (they usually appear in July). A Dock Bug was the first Shield Bug that I had seen locally this year, after shield bugs had a vintage year in 2024.

Six Spot Burnet Moth, Clothall Common, 20 June

Dock Bug, Therfield Heath, 10 June

Golden-bloomed Grey Longhorn Beetle, Royston, 10 June

Hummingbird Hawkmoth on the Ground, Royston, 24 June

It has been a poor year generally for orchids, although there was a good display of Pyramidal Orchids when I visited Clothall Common on the 20th and I also found a couple of Pyramidal Orchids on my local wildflower meadow. Common Spotted Orchids seem to have been particularly badly hit, with none seen by me locally. Very few were seen last year either, making me think that the dry, hardened ground in 2025 is not the only reason for this species' apparent demise. Fragrant Orchids appeared on Church Hill, but only small, wizened spikes were seen on my visits. Other plants fared better and I saw lots of the parasitic plant, Common Broomrape.

Common Broomrape near Wallington, 20 June

Pyramidal Orchids, Clothall Common, 20 June

My last visit to The Heath before a planned holiday abroad saw me on Church Hill on the morning of the 25th, when highlights included a female Dark Green Fritillary that allowed me to get close enough to get a decent photograph (males are rarely so obliging, being constantly on the move looking for females to mate with and fighting other males), and a mating pair of Dock Bugs.

Female Dark Green Fritillary, Church Hill, 25 June

Mating Dock Bugs, Church Hill, 25 June

Local Wildlife Sightings May 2025

 The hot weather continued into the start of May, with temperatures reaching around 27C, before declining dramatically as north-easterly winds set in from the 3rd. By the 4th the temperature in mid-afternoon was just 13C with a significant wind chill factor making it feel even colder, and I had gone from a light polo shirt to three layers, with a fleecy jacket on top. Whilst the weather was still hot on the 2nd I visited Church Hill and was encouraged to see at least ten (presumably) male Brown Argus butterflies flying over the low-cut grassy slopes, after this species did so badly in 2024. The cutting of the grass here in late summer last year should benefit this and other 'blue' species. Also seen were two Small Heath butterflies and small numbers of Peacock, Brimstone, Red Admiral, Comma, Orange Tip and Green-veined White butterflies.

Small Heath, Church Hill, 2 May

The warm weather soon returned, with prolonged sunshine during the middle of the month. Back on Church Hill on the 7th I couldn't find any Brown Argus butterflies (they only live in the adult stage for a few days), although a single Common Blue butterfly was seen at the bottom of the hill, a very early Broad-bodied Chaser dragonfly was seen nearby and a Mother Shipton moth (also seen on the 2nd) was photographed. This attractive, day-flying moth has a beaky 'face' marking on each wing, presumably giving it its name: see if you can make it out on the image (below). I was pleased to see that two male Spotted Flycatchers were 'singing' (a few high-pitched, squeaky notes) in Fox Covert on either side of the Therfield Road. This is a very early return for a species that can turn up as late as the beginning of June, but there had already been several reports of this species before 'my' birds were seen.

Mother Shipton Moth, Church Hill, 7 May

Singing Spotted Flycatcher, Therfield Heath, 7 May

Ox-eye Daisies, generally a flower of early June, were already flowering when I walked up onto The Heath on the 13th. I noticed that a fly was apparently sitting on one flower head. Closer inspection revealed that it had been captured by a predatory Crab Spider (stealth killers - they don't make webs), which was smaller than the fly (image below). On The Heath, three male Adonis Blues were flying on the Old Rifle Range, and looked to have been on the wing for at least a couple of days. This is fairly early for Adonis Blues, and was no doubt due to the fine, sunny weather in April and May.

Male Adonis Blue, Therfield Heath (Old Rifle Range), 13 May

Crab Spider with Fly Victim, Royston, 13 May

In 2023 and 2024, Chalkhill Blue butterflies did not emerge on Church Hill, although a few were seen flying there in the late summer of 2024. After only a few Adonis Blues were seen here in the spring of last year, and no second generation was seen, I assumed that the latter species had been lost to the poor weather at this site. However, when I checked the south side of Church Hill on a sunny afternoon on the 16th I was surprised to see several male Adonis Blues and a single female flying. As previously mentioned, Church Hill had been mown in the late summer of 2024 and was now covered in Horseshoe Vetch. Was there an unnoticed, very small second generation of Adonis Blues in 2024, or could the adults possibly have started life as eggs laid by last year's first generation? Another possibility is that they were re-introduced by whoever originally introduced them to The Heath. I guess that I'll never know. Present with the Adonis Blues were several Common Blues (all males) and Brown Argus butterflies, whilst in Fox Covert another Broad-bodied Chaser dragonfly was seen. A similar mixture of butterfly species was seen when I returned to Church Hill on the 21st, with slightly fewer Adonis Blues and Brown Argus, but even more male Common Blues.

Female Adonis Blue, Church Hill, 16 May

Roosting Brown Argus, Church Hill, 16 May

Male Common Blue, Church Hill, 16 May

Broad-bodied Chaser Dragonfly, Fox Covert, 16 May

Wasp Beetle, Royston, 19 May

Other sites visited in Hertfordshire during May included Wilstone Reservoir (Shelduck, Hobby, Swift, Common Sandpiper, Dunlin and Little Ringed Plover seen on the 8th) and Amwell, where I saw my first Red-eyed Damselflies and Banded Demoiselles of the year on the 12th.

Common Sandpiper, Wilstone Reservoir, 8 May

Four-spotted Chaser, Amwell, 12 May

Red-eyed Damselfly, Amwell, 12 May

The weather became more changeable towards the end of the month, although still with some warm, sunny days. Another visit to Amwell on the 23rd provided me with sightings of Cuckoo, Cetti's Warbler and a very early Green-eyed (Norfolk) Hawker dragonfly. A Great Crested Grebe caught and ate a large Crayfish whilst I was watching (image). The 26th saw me at Hillbrow (Letchworth), looking for Small Blue butterflies. I did eventually find half a dozen on a very windy day, but there was little else to see until a male Orange Tip butterfly fluttered by and conveniently stopped for me to photograph it.

Great Crested Grebe with Crayfish, Amwell, 23 May

Male Orange Tip Butterfly, Letchworth, 26 May

Small Blue, Letchworth, 26 May

A large flock of Ringed Plovers (12-15 individuals) arrived at Wilstone Reservoir in late May, staying for a few days. These birds, which looked slightly different to the birds that I see on the Norfolk coast, were likely passage migrants, heading to breeding sites in Northern Europe. I went to see them on the 28th. A Little Ringed Plover (resident?) and two Dunlins were also seen. Whilst I was in the area I took a walk along the Grand Union Canal from Wilstone village. A single, female White-legged Damselfly was seen on the bank of the canal, and I also had a bit of fun trying to photograph the very mobile Banded Demoiselle dragonflies on another windy day.

Ringed Plover, Wilstone Reservoir, 28 May

Male Banded Demoiselle, Grand Union Canal near Wilstone, 28 May

Locally, I found what I believe is an 'instar' Speckled Bush Cricket (only about 5mm long) on a walk along the Icknield Way east of Royston on the 27th and three Bee Orchids in a hollow on Church Hill on the 29th. When I came back with my macro lens to photograph the most impressive of the orchids on the 31st I was lucky to see a very early Marbled White butterfly, the first to be reported in the Herts. and Middlesex region and the first that I have ever seen in May. No Adonis Blues were seen on either visit, although they were reported by others visiting The Heath at the end of May and early June.

Immature Speckled Bush Cricket (?), Royston, 27 May

Bee Orchid, Therfield Heath, 31 May

'Record Shot' of Marbled White, 31 May

In the garden, recently fledged birds started to appear towards the end of the month including, surprisingly, juvenile Greenfinches. Blue Tits, Great Tits and Blackbirds also brought their young into the garden, whilst frenetic Starling activity and noise suggested that their young would soon be fledging.