The dry spell continued from late March into the second week of April, when the weather became more unsettled, but Royston seemed to miss the 'April showers'. The temperature varied enormously, from somewhat cool to very warm, with temperatures in the mid-20s on the 8th and early on the 9th. Numbers of our two commonest warblers, the Chiffchaff and the Blackcap, continued to build during the first week, until virtually every copse housed at least one individual of each. However, it was only in the second week that other summer visitors were noted in the Royston area, with three Whitethroats (singing males) recorded between Royston Hospital and The Heath on the 10th. I also found three male Wheatears, a passage migrant, just off The Heath on the same day. Sadly, Willow Warblers have also become passage migrants in the Royston area in the last few years (they were fairly common breeders not so long ago) and so their lovely song is only heard here from the middle of April until early May. I was lucky to see a singing male not far from the house on the 13th.
Male Wheatear, Royston, 10 April
A visit to the dung heaps north of Ashwell rewarded me with good sightings of several Yellow Wagtails, two Wheatears, two breeding-plumaged male Reed Buntings, a Meadow Pipit and one or two Pied Wagtails when I visited, again on the 10th.
Male Reed Bunting near Ashwell, 10 April
Male Yellow Wagtail near Ashwell, 10 April
The very warm weather on the 8th prompted me to get the macro lens out for the first time in six months and do a little bit of insect photography in my local woodland. Four species of ladybird (7-Spot, 14-Spot, Harlequin and Orange Ladybirds) were found, together with common wasps and a good variety of hoverflies. A few Orange-tip Butterflies and a single Holly Blue butterfly were also seen, together with the ubiquitous (when the sun was out) Peacocks and Brimstones.
14-Spot Ladybird, Royston, 8 April
Hoverfly (Syrphus Family), Royston, 8 April
The Willow Warbler was still singing on the 19th, on my return from a short holiday in Barcelona (I'll eventually put out a short post about the birds that I recorded there), but was not recorded subsequently. However, a second Willow Warbler was singing on The Heath (Old Rifle Range) on the 29th and I managed to get a photo of this one (below). Swallows returned in good numbers, being seen at and around their usual summer haunts during the later stages of April. I saw two at Hatchpen Farm on the 19th, but a far more interesting bird was the male Mandarin Duck seen at Hatchpen Pond on the same day, the first that I've seen on my local patch although I have seen them in Kelshall and Sandon. The bird was not seen on subsequent visits.
I recorded a total of seven Lesser Whitethroats on a walk round the villages of Therfield and Reed on the 21st, included one that showed surprisingly well for me (these birds are notorious 'skulkers') at Reed End (A further two were singing at the east side of Therfield Heath on the 29th). A House Martin, seen briefly at Phillup's Lake, was my first of the year. Corn Buntings (at least 40) were still flocking near Reed End, whilst similar numbers of Linnets were seen in the Therfield area, but in pairs or much smaller groups. Whitethroats were numerous by the end of the month, and a male was singing perhaps 300 metres away from the house in the field hedgerow that backs onto my estate.
Male Mandarin Duck (with Female Mallard), Hatchpen Farm (Reed), 19 April
Common Buzzard at Hatchpen Farm (Reed), 19 April
Willow Warbler, Therfield Heath, 29 April
A visit to Amwell on the 20th was rewarded with a sighting of two early Swifts. I also added Sand Martin, Sedge Warbler and Common Tern to my year list. A Little Ringed Plover was doing display flights in front of the viewpoint, and I managed to photograph it in flight - the image (by no means perfect!) is shown below.
Little Ringed Plover in Flight, Amwell NR, 20 April
April proved to be an exceptionally dry month, with no appreciable rain throughout. A prolonged zone of high pressure over the country gave us lots of sunshine, sometimes accompanied by a chilly easterly wind, but with temperatures climbing to 18-20C on occasion in the second half of the month. Migrant passage, presumably helped by the settled weather, was a week or two earlier than usual. I had a busy afternoon on the 24th, firstly heading east from Royston to visit Dernford Farm Reservoir, where no fewer than 18 Black Terns (a passage migrant that doesn't breed in the UK) had paused for a few hours, then heading west to Gamlingay where, after a bit of a 'yomp' along tracks in a massive, bare field, I found a single Dotterel (up to eleven were reported from here during the following week), my first for three years. Dotterel are almost extinct as a breeding bird in the UK, with just a few nesting on the Cairngorm plateau, where I have seen them in the past. At the end of the month, there was a major (record?) passage of Wood Sandpipers through the country, with birds seen in Hertfordshire at King's Meads, Amwell and Rye House. I saw six at the former site on the afternoon of the 29th. Like Whimbrel and Dotterel, Wood Sandpiper is a very rare breeder in the UK, exclusively in the north of Scotland, and these birds were probably heading for Scandinavia. Breeding was, of course, well under way by the end of the month, with a juvenile Robin, seen in my local woodland on the 21st, being the first passerine fledgling to be seen.
Black Tern in Flight, Dernford Farm Reservoir, 24 April
'Record Shot' of a Dotterel, Gamlingay, 24 April
Two Wood Sandpipers at King's Meads (Hertford), 29 April
I had hoped that the Crossbills at Scales Park would stay on to breed. However, I did not record any on visits near the start (2nd) and end (27th) of the month. Siskins were still around on the first visit, but not on the second when the only birds of interest were a couple of early Swifts and two Ravens, which were chasing away a Red Kite, presumably from near their nest site.
Butterflies and other Insects
The warm, sunny, dry weather in April provided an unusually large number of butterfly sightings. Brimstone and Peacock butterflies were seen throughout the month, although in gradually declining numbers, whilst the first generation of Holly Blue butterflies and the only generation of Orange Tips had excellent springs, being seen just about everywhere. Green-veined Whites increased in numbers as the month wore on, as did numbers of Speckled Wood butterflies. Indeed, this was the dominant species of butterfly seen on my visit to Scales Park on the 27th, when over 30 were seen. Red Admiral butterflies appeared towards the end of the month, suggesting that these were migrants from Europe, rather than over-wintering butterflies. No Commas were seen locally, indicating either a poor breeding season in 2025 or poor survival of wintering butterflies. On the 28th I saw my first local Brown Argus butterflies and the following day I recorded some Small Heath butterflies, the first to be reported in Hertfordshire. A few butterfly images are shown below.
Male Brown Argus, Royston, 28 April
Male Orange Tip, Royston, 24 April
Small Heath Butterfly, Royston, 29 April
My macro lens was put to good use in the second half of the month as I explored the local woodland looking for invertebrates. These included a 'new' sawfly, Tenphredo temula, which I haven't recorded before (although it is apparently common). Several different species of hoverfly were seen, of which one of the largest was Myathropa florea (image below). This is also locally common. However, the fly Myopa pellucida is, according to Brock, uncommon in the UK. I suspect that this is more to do with the fact that very few people bother looking for them! The flies were photographed mating on two separate days, and on both occasions I noticed that the upper fly (presumably the male) spent much of the time fanning its wings rapidly. Was this to cool them both down or was there another reason, and is this behaviour seen in other fly species?
Hoverfly, Myathropa florea, Royston, 29 April
Sawfly, Tenphredo temula, Royston, 27 April
Mating Flies, Myopa Pellucida, Royston, 21 April
Finally for April it is worth mentioning that I saw several Common Lizards, on or near The Heath.
