What a glorious spring we have been enjoying! Even in this warm, calm weather, with no strong winds or heavy downpours, it reminds us that the seasons for any of the spectacular nature displays are short and really shouldn't be missed!
This was recently demonstrated with butterflies. The Southern Streams Farmer Group are doing all sorts of conservation work across the area in the east of the Pewsey Vale and, at Tidcombe, they have been improving the habitat for butterflies on the downs. In April, on a Farm Walk and Talk at Tidcombe, lepidopterist Dr Sue Clarke mesmerised attendees on her knowledge of butterflies. Did you know that per square mile, chalk downland is rarer than rain forests? You will only find it in northern France and southern England. There are many species that are specific to the chalkland habitat and so there is real urgency and need to make the environment better so that they are flourishing rather than struggling through or dying out altogether.
One such chalkland specialist is the Duke of Burgundy butterfly and Tidcombe Down is being managed to make the environment as attractive as possible to this rare butterfly. Its lifecycle starts with the eggs being laid on the underneath of primrose or cowslip plants in May/June time. They can hatch in up to 21 days depending on weather, with the caterpillars feeding on the primrose or cowslip leaves during the dusk. The caterpillars don't grow very big (less than 2cm) so rather than seeing the caterpillars you will probably notice the holes in the leaves of the plants, normally in July.
After about 6 weeks, they will pupate in tussocks of grass (you can see from the image that grassy tussocks are plentiful on the Downs) and stay there throughout the winter, hatching into butterflies in the following spring at end of April/beginning of May. They live as butterflies for just a couple of weeks, perhaps into the beginning of June, so you don't have long to be able to spot one! We have been out looking daily, but haven’t seen one yet.
The 25th April is St Mark's Day and the hatching of the St Mark's fly (also known as the Hawthorn Fly) takes place on or around this date. This fly has very dangly, long back legs, so is instantly recognisable in flight. It is responsible for most of the apple tree pollination, so it’s an important insect. This image might not look very interesting, but it shows a spider's web which has caught quite a number of these flies and to the left is a bumble bee! You can't see the tiny, brown ants on the post that were also making a trail up to the spider's web.
When we saw them on the downs, it was the 26th April and the hawthorn was just starting to blossom. Isn’t nature clever? All these interdependencies between plants and insects and the rest of the food chain above them is fascinating but often very fragile.
The hawthorn blossom – or May as it is also known – is currently out and 2025 looks like another spectacular year for it! As with all these things, there is a relatively short time in which to see it at its best. The same goes for bluebells with outstanding displays in West Woods, Savernake, Wilton Brail and Bedwyn Brail currently underway – although the days have been hot, the nights have been cool which helps their flowering longevity.
None of these wonders is here forever – so don’t put off getting outdoors and experiencing the sight and the amazing scent of the flowers and watching out for the lifecycles of other species in action.
To find out more information about Southern Streams, visit their website
May we also recommend the Butterflies of Britain and Ireland WildID guide.
