A Southern Water reservoir site is set to be transformed into wildflower meadows brimming with butterflies, with help from Butterfly Conservation.
The charity is working with the water company to create a wildlife haven at Yew Hill, just south of Winchester, where it has an underground reservoir.
The firm has been carrying out improvement works at the site for several years but will soon start sowing 80 kilos of wildflower seed harvested from Butterfly Conservation's Magdalen Hill Down nature reserve just 6km away to the east of the city.
Butterfly Conservation South Downs Landscape Officer Fiona Scully said: "Our Magdalen Hill Down reserve is a beautiful example of chalk grassland, bursting with native wildflowers, rare butterflies and moths. We are delighted to be able to share vital native wildflower seed which comes from the site, itself restored by donated seed from other nature reserves. This field is now helping create new wildlife habitat nearby, benefiting local butterflies, moths and the rest of the ecosystem."
Butterfly Conservation has managed Magdalen Hill Down for decades as a flagship nature reserve.
The site is special because its pristine chalk grassland habitat was nearly lost to scrub, but was saved by the vision, expertise and dedication of local people. Over 80% of this type of grassland habitat has been lost across the UK in the past century.
In 1995, the charity was able to expand the reserve onto neighbouring land that was previously a farmer's field. By collecting seed from the best chalk grassland sites in Hampshire, Butterfly Conservation volunteers transformed the land into a high-quality, species-rich wildflower meadow that is now home to some of the UK's rarest and most beautiful butterflies such as Adonis Blue, Small Blue, Green Hairstreak and Marbled White - as well as dazzling Scarlet Tiger moth, Six-spot Burnet moth and crimson Cinnabar.
Butterfly Conservation had previously advised Southern Water on creating space for butterflies at Yew Hill, so when the company started improvement works there it asked the charity for help to create and restore wildlife habitat once the work was complete.
Southern Water ecologist Ben Benatt said: "Fiona took me for a day out at Magdalen Hill Down and explained that site itself was a restoration from former arable land, and it's so incredibly successful. It's also very unusual to find chalk grassland where you can get a decent harvest of seeds because most chalk grassland is on very steep slopes grazed by sheep - but Magdalen Hill Down has lots of relatively flat land with flower-filled meadows. It really is a rare and special place."
Southern Water hired wildflower seed company Emorsgate, which brought a tractor to Magdalen Hill Down with a device called a brush cutter that harvested a 2.5 hectare area in July, collecting a whopping 80kg of seed.
Among the wildflower species collected were Sainfoin, Rough Hawkbit, Meadow Vetchling, Common Sorrel, Salad Burnet – a particularly important caterpillar foodplant for the Grizzled Skipper butterfly - and Yellow Rattle, which is a parasite on grasses, suppressing their growth and giving other wildflowers more of a chance to thrive.
In time, this mixture should sustain many of the same specialist butterflies which thrive at Magdalen Hill Down such as Chalk Hill Blue, Grizzled Skipper and Green Hairstreak, as well as generalist species such as Marbled White and Small Skipper.
That seed is now being stored at a specialist temperature and humidity-controlled unit until the spring, when the seed is set to be sown.
On his visit to Magdalen Hill Down, Ben was also inspired by the 'scrapes' which Butterfly Conservation has created - long, shallow depressions in the ground where the soil has been scraped off and piled up nearby, creating small, south-facing mounds where particular wildflowers and butterflies thrive, and he is now hoping to replicate those at Yew Hill as well.
Fiona said: "We are so pleased that Southern Water have been inspired by Magdalen Hill Down to create their own wildflower meadows for butterflies and moths. We are hugely grateful and proud of all the work that went into transforming the field back to a wildflower meadow so we can now give wildflower seed from land that thirty years ago was an arable wheat field.
“Any construction project can disrupt natural habitat, but as our work at Magdalen Hill Down has shown, wildflower meadow is a habitat that we can establish relatively quickly and will be of huge benefit to butterflies, moths and a host of other wildlife. What's more, this new habitat has potential to be even better than what was there before."
Find out more about Magdalen Hill Down and plan a visit at butterfly-conservation.org/our-work/reserves/magdalen-hill-down-hampshire
- Would you like to help us help butterflies and moths? Find out more about supporting Butterfly Conservation.