Bumps and ‘bunkers’ to provide new homes for the small blue

Bleak March: in the week after the big storms, the blossom of a cherry tree on Roundshaw stood out against the grey Croydon backdrop

NATURE NOTES/MAR 2022: Be careful what you wish for, as the February storms saw nature perform a handbrake turn before the first guided walk of our year-long nature watch project. By STEVEN DOWNES

Road runner: even before we’d got to the Downs, a redwing was spotted alongside the busy A23

I’d muttered something about wanting the first group walk on Roundshaw Downs to be bleak, so that somehow, those not familiar with the place could get a sense of how hostile it can seem sometimes.

Careful what you wish for.

After the first few weeks of the year had seemed to have the flora and fauna around the downs hurtling towards spring, the arrival on our shores at the end of February of the vicious storms, Dudley, Franklin and Eunice, saw nature do the equivalent of a hand-brake turn.

By the time of our walk at the start of this month, we were firmly back in winter.

Bunkered: Dave Warburton (in shorts) explains the ecology behind his golf bunkers

The Downs, being chalk grassland, usually drain and dry pretty quickly, but the torrents of rain that had been deposited there in the previous couple of weeks had left puddles and mud. Lots of mud.

And the cruel north wind cut through with an extra edge.

Our small group of hardy souls curious about conservation met close to the Purley Way. One of the wonders of Roundshaw is how close this thriving nature reserve is to the noisy, polluting urban motorway that is the A23.

Yet even in this hostile environment, we were able to spot signs of nature: a redwing, hopping along the pavement, in and out of the ornamental shrubbery alongside Costco, almost as if it were tame.

As we rounded the corner at the RAF war memorial, we soon spotted another rarity for March in south London: a bloke wearing shorts.

Dave Warburton is Sutton’s senior biodiversity officer. Thanks to contacts at Surrey council’s countryside partnerships, Dave had agreed to give up his Saturday morning to guide our group around the Roundshaw site, explaining how over the past 15 years he has been working to turn what was, at the end of the 1950s, an industrial site, the old Croydon Airport runway, into the thriving habitat for rare species of plants, insects and birds that it is today.

Scarce: the small blue, which is thriving at Roundshaw

Introductions done, our group set off, up towards the bund that had been built along the borough boundary between Croydon and Sutton, and then proceeded up the northern side of the nature reserve.

There, in the thick, varied hedgerow that separates the reserve from closely cut football pitches, the hawthorn had not yet quite burst into blossom. Three weeks later, and this weekend the reserve is now flanked by a wall of white. You should catch sight of it before it is gone.

Ranger Dave was in his element, his knowledge and understanding flowing out as he bent down to identify this vetch or that first sprout of what would become, in just a few weeks, a vivid ox-eye daisy or greater yellow rattle.

He explained how 10 years ago, the re-wilding process had seen the installation of the fenced paddock areas so that while a large part of the grass downland is mown regularly, a significant section now is left to be grazed by the small herd of Sussex cattle that visit each year.

Bumpy: the lack of mechanised mowing has allowed hundreds of yellow meadow ants nests to be created

The absence of any mechanical mowing has seen hundreds of grassy bumps appear around the grazed area, created by colonies of yellow meadow ants, a vital part of the re-emerging eco-system, which now offers habitat for the endangered skylark and the meadow pipit, another ground-nester and which has a similar display and song flight which ends with its “parachuting” back to the ground on stiff wings.

Warburton explained his vision that the unmown paddock areas might one day be extended further across the Downs, providing even greater area for the biodiversity of what is a very rare chalk grassland habitat.

And across on the playing fields to the north, Ranger Dave pointed to a long, man-made mound, another part of the re-wilding of the area.

Indeed, all around Roundshaw were a collection of what appeared to be golf bunkers, without the sand. Were they going to build a golf course here?

On the contrary, it was all part of a scheme to make the place even more habitable for another rare species, the small blue, a beautiful butterfly which, because of the loss of habitat and its dependence on a single plant for food, kidney vetch, is reckoned to have halved in number in the last 50 years.

Warburton has been busy in a little JCB, creating scrapes in and around the paddocks, providing the bare soil, and chalk, which are an essential part of the butterflies life cycle.

Poised: Roundshaw’s resident kestrels enjoy the habitat

The longer barrow on the playing fields had been created as part of the Brilliant Butterflies project, together with the London Wildlife Trust, and which has seen similar bare earth mounds created in South Croydon Rec, Beddington Park and other open spaces around Croydon and Sutton, as the naturalists seek to provide “nature corridors” for the small blue, that it might extend and expand its range and avoid the feared oblivion.

Yet while Warburton was carefully explaining all this to us, he was being rudely up-staged.

Over one shoulder, one of Roundshaw’s eye-catching kestrels was in flight, hovering above some prey or other.

And meanwhile, maybe 200 feet above us, despite the grey sky and northerly wind, a skylark was performing its song, loud and proud and wonderful. Most of those in our small group had never visited Roundshaw before, one or two had not witnessed a lark’s song for many years, if ever at all. All were rapt. Dave Warburton’s work is working.

Blooming: this week’s warmer weather has encouraged the blackthorn to blossom

It really wasn’t that bleak at all.

We will all be back on another walk across the Downs soon enough, hopefully in mid-May (details to be announced; watch this space), along with Dave Warburton, when his shorts hopefully won’t seem like such a piece of bravery, to see how the whole place is coming along, and maybe to spot a rare butterfly or two.

In the meantime, Ranger Dave, the biodiversity officer, is on the lookout for conservation volunteers, with a volunteering Sunday on April 24. Email biodiversity@sutton.gov.uk for more information and to get involved with undertaking habitat management (lots of cutting back the brambles) on site. All training and tools provided.

Otherwise, the Biodiversity Team provides volunteering opportunities on Tuesdays through Thursdays every week of the year, undertaking practical habitat management, including botanical surveying during the summer months. More info here.

Previous Nature Notes: February: Heard before they’re seen, skylarks soar back over Roundshaw
Previous Nature Notes: January: Up on the Downs, watching for the missing signs of winter

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About insidecroydon

News, views and analysis about the people of Croydon, their lives and political times in the diverse and most-populated borough in London. Based in Croydon and edited by Steven Downes. To contact us, please email inside.croydon@btinternet.com
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2 Responses to Bumps and ‘bunkers’ to provide new homes for the small blue

  1. Lewis White says:

    Thanks for this encouraging article, and I am sorry that I couldn’t join the walkabout.

    It is wonderful that the once close-mown grass airfield is now in the process of re-becoming a chalk downland pasture, thanks to the efforts of the conservationists (human and 4 legged ones from Sussex) and the Councils involved.

    I just wanted to mention the “bund” which forms the article mentions as being the boundary between Sutton and Croydon.

    This boundary and the bund itself are very ancient, and may be Saxon, reflecting the Romano-Celtic past, as it is even possible that underneath it lies a section of the Roman Road from Stockwell (where it diverged from the London to Chichester Road , well-known as Stane Street) via Streatham (Anglo Saxon name Streat reflects a Roman Road) to Godstone , and then onwards to the Brighton area. This road would have given access to and from London, the South Coast and the Iron mines of the Weald.

    The bit from Streatham to Purley and on to the North of Godstone is still a bit of a mystery.
    It might well have had more than one route.

    The current main road from Streatham into Croydon looks very direct and very “Roman”.

    Coming in the opposite direction, from the Sussex end, the route comes in a very, straight line over Tilburstow Hill into and Northwards from Godstone village , and then seems to do a looping wiggle round the Eastern rim of the deep Caterham Valley, then ( a bit muzzy in this area) descends to Whyteleafe, then goes up over and along the top of Riddlesdown, and diagonally down into Purley around the Godstone road railway bridge. Parts seem clear, others not. Maybe it avoided the steep-sided deep, possibly marshy, and perhaps ambush-prone deep valley of the Bourne at Kenley.

    It then crossed the valley bottom at Purley (possibly also rather marshy in those days) and then ascended quickly the Russell Hill road area, and up a lane (now a bridle path) called Coldharbour Lane. Reaching the top of the ridge, a superb view Northwards opens up over what is now the Purley Way playing fields and airport site, then across Croydon and SW London. In Roman times, the chalklands here might well have been rather like the similar slopes of Banstead Downs are nowadays– scrubby but open. Cleared of trees in the Iron age, and grazed – but I think I am right in saying that no-one knows for certain. If a paleo-botanist is reading this, it would be good if they could comment !

    What is very clear 2000 years later, is that the boundary between Sutton and Croydon (between Beddington Parish and Croydon Parish) from the top of Purley way down to the Wandle springs at Waddon Ponds is very “Roman Road” in its straightness. The name Coldharbour, in spite of some views to the contrary, occurs in the SE of England, and seems to be connected to settlement located just off a Roman Road. Coldharbour was around where the histroric Waddon Tithe Barn is now– near 5 ways. There is another Coldharbour, better known, at Brixton, off the same Roman Road.

    In the waterless chalklands on North east Surrey, fresh springs of water surely would have been sought out by both Celts (who venerated springs, such as at Ewell) and by incoming Roman road builders and traderrs, who must have wanted fresh water in good quantity for troops and pack/ draft animals. There was a Roman Bathouse and villa very nearby at Beddington, which must have been connected by track to a more major road.

    My guess (and I am not sure if anyone has investigated) is that the bank or bund mentioned in the IC article above may well be right on top of the Roman Road. Might even be the core of a road.

    The bank is shown as the “Mere bank” on old maps.
    Mere can mean in Anglo saxon “boundary”, (or mark) spelled “Meare” It can also mean a mere or pond, spelled “mere” . At Waddon , the ponds were probaby man made, but the springs are natural. They are amazing today, and in Celtic times must have been like an oasis in a desert of parched chalklands. Maybe we have here a double-meaning “boundary on the bank of the pond” ? My money is on “boundary” bank.

    A Roman Road was and often remains a very good landmark– raised several feet above the local general land surface, with a ditch or ditches both sides, the overall width of road and distance between banks depending on importance of the road.

    Romano-Celts probably used the roads as boundaries between agricultural estates. When the new Saxon overlords turned up, they might well have confiscated or (if they were nice) bought such estates, or just decided to use the Roads as their own boundaries. So it would not be surprising if a Roman Road lurked below or inside the bank.

    Another possibility is that another Roman Road ran from the top of Purley Way diagonally across the downs via Violet Lane and over Duppas hill, to meet the main Wandle Springs around the Parish Church in what became Old Town. Then onwards up on to the ridge at Broad Green, and then on to Streatham. The name “Roman Way” is a modern name but was based on remains found at the site.

    Just as with roads in our own times, the Romans built new roads, short-cuts, improved sections and bypasses, so that the road pattern evolved to meet not just military but emerging and changing trade needs.

    Ongoing research of interested groups such as Surrey County Archaelogical Society and the Roman Road Research Association might well result in more answers as to the routes of Roman Roads in Croydon. There are currently very few RRRA members in our area, but in many parts of the country, they are finding hundreds of miles of hitherto lost roads.

    I am wondering what protection is given to the Mere Bank across the Roundshaw Downs and Purley Way Playing Fields? Sadly, a large section must have been destroyed when the airport industrial estate was built. It would be a criminal shame if the remaining sections were damaged.

    If any Inside Croydon readers are interested to the Mere Bank, and the possible routes of Roman roads in our area, with the opening up of the world post-covid (we hope) , perhaps Inside Croydon could bring them together ?

    “Walking the Roman Road from Waddon to Caterham ” could be another great Inside Croydon excursion. Or even a book !

  2. Ian Kierans says:

    very interesting

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