Butterflies on Rushmere Common - a 2016 survey

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BUTTERFLY REPORT 2015

BUTTERFLIES ON RUSHMERE COMMON - A 2016 SURVEY RICHARD STEWART Rushmere Common, on the eastern edge of Ipswich, is an extensive ‘green lung’ enjoyed by golfers, dog walkers, joggers and naturalists. Plates 10–14 show some of the habitats on the site. The edge bordering Heath Road is in the 2 km recording tetrad TM1944 and the rest in 2044. I will differentiate between these two in this study. Nine visits were made, one in late April and then two per month until the end of August. Although a relatively fixed route was followed this was not walked according to the criteria for a transect walk.

The route was through the large concrete blocks near Heath Road, then a left turn down a sheltered lane later to be full of flowering brambles. At its far end there is more shade and many oaks. Just before the golf club building appears, a right turn takes me out onto the golf course, passing areas of shorter and longer grasses, large mature gorse stands, trees including rowan and oak and several stretches of heather.

The route goes to the Woodbridge Road end of the lane that runs parallel to Linksfield, at the eastern edge of the Common. This lane is also partially shaded and at its end a detour to the right takes in the area around the pond. Woodland is next, with a small and then larger meadow, followed by another shaded lane up to the prominent water tower. Then the adjacent playing area is crossed before turning into a second lane, then left across the golf course and through extensive beds of heather and finally taking the main path back to the starting point.

There are two significant recording results from Rushmere Common. The first, (Stewart, 1998), listed 10 species recorded on a Butterfly Conservation meeting dated 12 May 1998. Its significance was that two of these had exceptionally high scores: 369 Small Coppers and 345 Green Hairstreaks. ‘Twenty Species In Two Hours’, (Goddard, 2000), speaks for itself, but the author adds that 27 species had been recorded on Rushmere Common, if one includes the rare Camberwell Beauty, found in a Linksfield garden just a few yards from the Common.

Results were as follows: 21 April- just a single Comma in each tetrad, on a cloudy day.

12 May- the target species was Green Hairstreak and two were soon seen flying along the first lane.

TM1944 - 2 Green Hairstreak, single Orange Tip, Brimstone and Holly Blue, 2 Speckled Wood.

TM2044 - Single Green Hairstreak, Orange Tip and Small Copper, 4 Holly Blue, 3 Speckled Wood.

The Brimstone is relatively rare on this site and a detour was made to walk the long and tall avenues of Gorse at the eastern end, normally the best area for Green Hairstreaks, but only one was found. Gorse and Broom are the two larval food plants normally used by this species in Suffolk.

27 May - TM1944 - 3 Speckled Wood and a very welcome 2 Brown Argus in long grass close to the entrance.

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TM2044 - 1 Large White, 1 Orange Tip, 3 Holly Blue, 3 Speckled Wood.

The Speckled Wood is normally most frequent at the shaded part of the lane in TM1944 and along the Linksfield lane in TM2044.

4 June- TM1944 - 2 Speckled Wood, 3 Holly Blue.

TM2044 - 4 Speckled Wood, 1 Brimstone near the pond, 1 Common Blue in the larger of the two meadows.

This meadow, a remnant of the extensive grassland that has disappeared under housing development, has a rich flora: Cowslips dominate in spring, then Meadow Cranesbill and Horseshoe Vetch cover much of the meadow, followed by Scabious and Knapweed, with other nectar sources that will be mentioned later.

21 June: TM 944 - 3 Speckled Wood, 1 Meadow Brown.

TM2044 - 2 Speckled Wood, 5 Meadow Brown, 1 Brimstone, 1 Small Heath.

The total of 13 butterflies was disappointing especially as much of the longer grassland was covered with flowering Hawkweed, a good nectar plant. So far none of the three ‘white’ butterflies had been seen close enough to identify. At one point a Muntjac was noted, walking slowly across the golf course to new cover, behind the backs of several golfers who failed to see it.

14 July - TM1944 - 2 Essex Skipper, 1 Speckled Wood, 1 Comma, 4 Meadow Brown, 33 Ringlet.

TM2044 - 33 Small Skipper, 5 Essex Skipper, 4 Large Skipper, 2 Large White, 2 Purple Hairstreak, 8 White-letter Hairstreak, 1 Small Copper, 3 Speckled Wood, 38 Meadow Brown, 78 Ringlet, 1 Small Heath.

Flowering Bramble on a relatively sunny day led to much higher numbers, and sitting on a seat in the larger meadow, surrounded by Clover, Knapweed, Scabious and Bramble nectar sources, until the cloud went, added to the total. The area of the lane close to the water tower is a traditional White-letter Hairstreak site and despite a growing breeze I eventually found two. Two Purple Hairstreaks were located in oaks near the playing field and along the second lane a long watch produced twenty movements of White-letter Hairstreaks, including two flying pairs. I estimated about eight different individuals.

19 July - TM1944 - 3 Small Skipper, 1 Large Skipper, 1 Red Admiral, 2 Speckled Wood, 2 Gatekeeper, 5 Meadow Brown, 21 Ringlet.

TM2044 - 67 Small and Essex Skipper, 2 Large Skipper, 5 Large White, 1 Small White, 2 Green-veined White, 5 Purple Hairstreak, 6 White-letter Hairstreak, 2 Small Copper, 1 Holly Blue, 1 Red Admiral, 1 Comma, 1 Speckled Wood, 6 Grayling, 11 Gatekeeper, 22 Meadow Brown, 94 Ringlet.

On a hot and sunny day this was easily the best count, with 17 different species recorded. The number of skippers necessitated the Sm/Essex identification usually applied in transect walks and the combined total will reflect this. Two Purple Hairstreaks were seen near the water tower but numbers in the larger meadow were reduced by the flowering Buddleias, on higher ground, facing north and largely shaded out by tall surrounding trees.

3 August - TM1944 - 1 Large Skipper, 5 Purple Hairstreak, 2 Speckled Wood, 2

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BUTTERFLY REPORT 2015 BUTTERFLIES ON RUSHMERE COMMON

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Grayling, 10 Gatekeeper, 1 Meadow brown, 2 Ringlet.

TM2044 - 5 Sm/Essex Skippers, 1 Brimstone, 5 Large White, 3 Small White, 1 Small Copper, 1 Common Blue, 1 Holly Blue, 1 Peacock, 1 Comma, 17 Speckled Wood, 11 Grayling, 42 Gatekeeper, 15 Meadow Brown, 1 Ringlet.

Sixteen species were recorded with grayling being seen at six different locations, including one across Heath Road and within the hospital grounds. As often occurs with this species, several landed on my hands or clothes. A particularly good place for Grayling is about three hundred yards from the end of the walk, an oval track surrounded by heather, to the left of the main path. The dominant plants were Yarrow, Hawkweed, Ragwort, Thistle, flowering heather and bright drifts of Rosebay Willowherb. This and the previous walk took much longer, approximately two and a quarter hours.

16 August - TM 944 - 1 Speckled Wood.

TM2044 - 1 Holly Blue, 3 Speckled Wood, 6 Grayling, 5 Gatekeeper, 3 Meadow Brown, 2 Small Heath.

With just twenty-one butterflies recorded, on a day of initial sunshine but growing cloud, the walk took just one hour and forty minutes. Seven different nectar sources were still available but in limited amounts.

Summary - Numbers of Butterflies Seen- in descending order Ringlet 229 Small/Essex Skippers 115 Meadow Brown 94 Gatekeeper 70 Speckled Wood 52 Grayling 35 Holly Blue 14 White-letter Hairstreak 14 Large White 13 Purple Hairstreak 12 Large Skipper 12 Small Copper 5 Comma 5 Brimstone 4 Small Heath 4 Small White 4 Green Hairstreak 3 Orange Tip 3 Common Blue 2 Brown Argus 2 Red Admiral 2 Green-veined White 2 Peacock 1

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This total of twenty-four species lacks any Small Tortoiseshells or the migrant Painted Lady, both species normally expected here. However, it must be remembered that just nine visits were made, compared to the twenty-six on a butterfly transect walk, so the figures above do not constitute an accurate year index per species.

Nevertheless, some numbers were very low, especially Small Copper and Green Hairstreak, compared to numbers mentioned earlier, though admittedly eighteen years ago.

More optimistically, the four Brimstone sightings were welcome, at a site with little or no Buckthorn, the larval food plant. The two White-letter Hairstreak colonies appear healthy, though at each some Elm die-back needs attention. The dispersal of Grayling across the Common suggests a strong presence compared to its declining national profile. The fifty-two Speckled Wood sightings emphasise the amount of edge-of-woodland dappled shade that this species prefers. Holly Blue appears to have had a good year in its normal five-ear ‘rise and decline’ relationship with the parasitic ichneumon wasp, Listrodomus nychemerus.

Despite nine visits, and my previous knowledge of this area, I could not ascertain any specific reasons for poor numbers in several species. No fires were noted, all the different habitats appeared intact and the summer cutting back of vegetation was in all cases limited to the edges of habitats.

References Stewart, R. (1998). ‘1998 Field Trips’. Suffolk Argus 15: 8.

Goddard, S. (2000). ‘Twenty Species in Two Hours’. Suffolk Argus 19: 16–17.

Richard Stewart ‘Valezina’ 112, Westerfield Road Ipswich, IP4 2 XW

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R. Stewart

BUTTERFLY REPORT 2015

R. Stewart

Plate 10: Rushmere Common: one of the best areas for Grayling (p 39).

Plate 11: Rushmere Common: areas of dappled shade are ideal for Speckled Wood.

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R. Stewart

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R. Stewart

Plate 12: Rushmere Common: flowering Hawkweed on the edge of the golf course.

Plate 13: Rushmere Common: View down the lane close to the start of the butterfly walk (p 39).

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