Iping & Stedham CommonInvertebrate Survey

Andy Phillips & Graeme Lyons

Iping & Stedham Common Invertebrate Survey

Contents1. Introduction2.Survey Areas3.Methodology4.Results5.Species Accounts6.Conclusions & Discussion7.References8.Acknowledgments

(Additional separate documents)

Appendix 1. Map of Survey Areas.Appendix 2. Taxonomic check list of the Spiders of Iping and Stedham Common.

Appendix 3. Iping and Stedham Common Data Analysis (spreadsheet).

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Bombus jonellus Evarcha arcuata Bog Bush-cricket

SummaryAn invertebrate survey of Iping and Stedham Common Nature Reserve, with a particular focus on

spiders, was commissioned by Sussex Wildlife Trust during 2012 due to the listing of rare spider species on the SSSI citation and recent records showing the spider fauna of the site to still be very

diverse.

An invertebrate assemblage methodology and analysis was used to study three selected survey areas in

detail over four dates between May and October 2012. In total 286 species from 15 invertebrate groups were recorded on the four visits within the three survey areas. This included 119 spider

species, 44 of which were new to the site, including four new species for Sussex - Philodromus praedatus, Hygrolycosa rubrofasciata*, Satilatlas britteni, and Zelotes petrensis. The site now has a spider check list of 204 species which represents about 30% of the British spider fauna.

The survey showed the site was very rich in invertebrates, especially spiders. An analysis of the habitat

resource associations and feeding biology of the species recorded in regard to differences in grazing management between the three survey areas was undertaken. This showed that Stedham was the most invertebrate rich and work to control scrub and pine and re-introduce grazing has been very

successful in producing the ideal heathland habitat for a rich invertebrate fauna. Comparison of the two Iping survey areas showed that the newly introduced grazing was starting to have an effect on the

invertebrate fauna but this is at a very early stage and a repeat of this survey in 5-10 years would be very beneficial to monitor the continued effects of grazing.

*(Recorded outside of the timed survey visits so not listed in the results.)

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1.! IntroductionIping & Stedham Common is a Sussex Wildlife Trust Nature Reserve situated near Midhurst, West

Sussex. The site is within a SSSI and is a designated Local Nature Reserve. It is part of a complex of heathland sites, which include Ambersham and Woolbeding, that make up the most extensive area of

heathland in West Sussex. This area lies within the Wealden Greensand Natural Area and are the remnants of a previously extensive area of Wealden heaths which have been lost to conifer plantations, agriculture and mineral extraction. (Iping & Stedham Scientific Committee, 2007)

The reserve is well known for its invertebrate fauna, especially spiders for which it is very rich and a

number of rare spiders have been found at the site. Southern lowland heathland is probably the richest and most important habitat in Britain for spider conservation. A number of very scarce species are restricted to heathland in southern Britain and the heathland complexes of West Sussex, Hampshire,

Dorset and Surrey contain the most important heathland sites in Britain.

Stedham Common had become degraded due to scrub invasion and a lot of work has been undertaken over the last decade to reduce scrub and pine and re-introduce grazing to restore the heathland. Within Iping a grazing trial has recently been established in combination with heather mowing &

burning as well as birch control and scrape management.

This monitoring survey was commissioned to assess any difference between these three areas in regard to grazing and an assessment of habitat resources within the three survey areas identified. The survey is particularly focussed on spiders due to the sites importance for this group but in all 15 invertebrate

groups were chosen to study and compare. (See table 1. for a list of the invertebrate groups recorded during the survey.)

Work during the late 60’s on the spiders of Iping and Stedham resulted in a list of 109 species being recorded. An invertebrate survey in 2007 added a few extra spider species to the site and proved the

reserve was still very rich in spiders with 160 species recorded.

This report outlines the methodology used to monitor the three survey areas identified, presents the results of the survey with an analysis on habitat resources and invertebrate biology, provides species accounts for species with conservation designations recorded during the survey and assesses the

results in relation to grazing effects and other differences between the survey areas.

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2.! Survey AreasThree survey areas were identified for survey, all of approximately 5 ha in size. See appendix 1 for a

map of the site and locations of the three survey areas.

1. Stedham Survey Area (Area centroid - SU 8548 2192)

The Stedham Survey Area was predominately H2c Calluna - Molinia sub community, with smaller areas of M1 Bog pool community, H2a Calluna - Ulex minor heath, and M25a Molinia mire.

The area also had a significant number of scattered pine trees, a small stand of pine trees, small blocks of gorse and the area was surrounded by woodland edge, including a small area of W10a woodland to

west of the area and a patch of W16a woodland to the south-east of the area.

Areas of wet heath and open water were much more extensive in this survey area than the two Iping

areas and bare ground was more limited being present predominantly along the main footpaths through the area. Also the bare ground was of a much harder grittier nature than the loose sandy areas

of bare ground within Iping.

This area has in the past suffered from extensive scrub succession. It is evident a great deal of work to

remove scrub and pine had been undertaken, with good heather regeneration in the cleared areas. This area though was still more scrubby in nature than the two Iping survey areas and was in much closer

proximity to woodland edge. Grazing was in evidence during the survey by a small number of British Whites. The cattle appeared to favour the grassy wet heath areas within the survey area.

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2. Iping Grazing Trial Survey Area (Area Centroid - SU 8458 2185)

The Iping Common (Grazing Trial) survey area was predominately H2a Calluna - Ulex minor heath and H2c Calluna - Molinia sub community, M25a Molinia mire with smaller areas of U2a Deschampsia

grassland.

Small blocks of gorse scrub, birch scrub and scattered pines were also present within this survey area.

Also the U2a Deschampsia grassland within this survey area was grazed much shorter than the other two survey areas, with an abundance of tormentil (Potentilla erecta) present within the turf. Bare

ground within this survey area consisted of the eroded, sandy footpaths and scrape management.

Grazing by a small number of British Whites was in evidence during the survey. The cattle appeared to favour the Deschampsia grassland within the survey area and rested around the water supply near one of the entrances into the grazing trial area. There was an abundance of dung in this location present

on the sandy path and surrounding area.

3. Iping Control Survey Area (Area Centroid - SU 8421 2200)

Iping Common (Control) is predominately H2c Calluna - Molinia sub community and M25a Molinia

mire with smaller areas of U2a Deschampsia grassland and M1 Bog pool community.

Blocks of gorse scrub, birch scrub and scattered pines were also present within this survey area. Bare

ground within this survey area consisted of the eroded, sandy footpaths and scrape management. No grazing was present within this survey area.

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3.! Methodology

Two key methodologies were used to survey these three survey areas. The survey areas were sampled four times during the year on 29th May, 30 July, 19 September, and 25 October 2012.

1. Sweeping, beating and vegetation sampling using an aerial net was used on tall vegetation, heather, the lower branches of trees and scrub, and pollen & nectar sources. Bare ground and

dung were also inspected. Each survey area was sampled for exactly one hour each on each survey date.

When using this methodology a slow transect is walked through the habitat with equal effort applied to sweeping vegetation and beating scrub and lower branches of trees, as well as inspecting any areas

of bare ground and cattle dung. This method has been used on a number of invertebrate assemblage studies and results in finding the greatest number of species in the shortest period of time (Collins, G.,

Edwards, M., Hodge, P. & Phillips, A. 2006). After about 1 hour the number of new species recorded starts to decline so in most cases only 1 hour is required per survey area. This enables the survey to provide comparable data if repeated.

The invertebrates recorded using this method are those associated with key habitat resources such as

herbaceous vegetation, woody vegetation, seed-heads, pollen & nectar sources, dead wood, dung and bare ground. These habitat resources are crucial in terms of conservation and management and this methodology is very good at providing data that can be used to inform management.

For this method weather is very important and only warm days with a third or less cloud cover is

present and wind speed below force 3 was chosen for the survey. The surveys were conducted between 10am-3pm as this is the warmest part of the day and best for recording using this method.

Each time the survey areas were sampled a similar but not exact route was taken through the habitat to ensure all parts of the survey area are visited during the survey visits. A different survey area was

sampled first on each visit so that the order of sampling the three survey areas was rotated to eliminate bias due to the time of day and surveyor fatigue.

On each visit every species found and identified was recorded. A number of species were recorded in the field but the majority of species recorded required the collecting of specimens for accurate

identification using microscopy. The specimens collected are preserved and stored in the private collections of the authors.

2. Sampling of moss, heather, pine and gorse litter using a sieve was predominantly employed on the October visit.

Areas of suitable humid areas of moss, litter at the base of pine trees & gorse scrub and patches of dead heather were chosen and sampled.

This method is particularly effective at sampling not only detritivore and detritivore predators but also

nocturnal predators searching out humid refuges during the day.

Weather is not as critical for this methodology although relatively still overcast weather with high

humidity is preferred for this method and was chosen for this visit.

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4. ResultsIn total 286 species from 15 invertebrate groups were recorded on the four visits within the three

survey areas. Three UK BAP species, one IUCN (2001) - Vulnerable species, two IUCN (pre 1994) - Rare species, four Nationally Scarce A , 21 Nationally Scarce B species and one uncategorised

Nationally Scarce species were recorded. The number of species categorised by invertebrate group and conservation status per survey area is presented below in table 1.

Table 1. No. of species per invertebrate group.

Species Group Stedham Iping (Grazed) Iping (Control) All Survey Areas

All 181 154 144 286

Aculeata 7 15 8 18 (6.3%)

Araneae 79 59 53 119 (41.6%)

Auchenorrhyncha 5 2 2 5 (1.7%)

Coleoptera 30 30 30 57 (19.9%)

Dermaptera 1 1 1 1 (0.3%)

Dictyoptera 1 0 1 2 (0.7%)

Diptera 8 8 5 13 (4.5%)

Hemiptera 12 11 14 21 (7.3%)

Isopoda 1 3 0 3 (1%)

Lepidoptera 23 19 19 29 (10.1%)

Neuroptera 1 2 1 3 (1%)

Odonata 4 1 1 4 (1.4%)

Opiliones 3 3 3 5 (1.7%)

Orthoptera 6 2 5 9 (3.1%)

Pseudoscorpionida 0 0 1 1 (0.3%)

No. of species occurring in all three survey areas = 61 (21.3%)No. of species occurring in two survey areas = 71 (24.8%)

No. of species occurring in one survey area = 154 (53.8%)

No. of species occurring at Stedham = 181No. of species only occurring at Stedham = 72 (25.2% of total)

No. of species occurring at Iping = 214No. of species only occurring at Iping = 105 (36.7% of total)

No. of species shared between both Iping areas = 84 (29.3% of survey total, 39.2% of Iping total)

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Table 2. No. of species per conservation status.

Conservation Status Stedham Iping (Grazed) Iping (Control) All Survey Areas

UK BAP 1 3 2 3 (1%)

IUCN (2001) - Vulnerable

1 1 1 1 (0.3%)

IUCN (pre 1994) - Rare

1 1 1 2 (0.7%)

Nationally Scarce A 3 2 0 4 (1.4%)

Nationally Scarce B 15 10 8 21 (7.3%)

Nationally Scarce 0 1 0 1 (0.3%)

Southern Restricted 14 10 10 21 (7.3%)

Southern Restricted + conservation status species.

34 25 20 50 (17.5%)

Widespread 57 46 45 91 (31.8%)

Universal 89 79 78 139 (48.6%)

Heathland Specialist

21 21 19 27 (9.4%)

UK BAP species are taxa listed as species of conservation concern in the United Kingdom Biodiversity

Action Plan. The criteria used to select these species is based on whether a species is endemic to the UK, globally restricted species where the UK supports a significant proportion of the global population, rapidly declining and endangered species.

IUCN (International Union for Conservation of Nature) designations replace the now deprecated RDB

(Red Data Book) designations. Whereas RDB designations are based on the number of 10km squares a species has been recorded (hence based more on recorder effort than actual rarity), the IUCN designations are based on population, population decline and fragmented and restricted distribution

patterns. The ‘pre 1994’ designations directly replace the RDB designations e.g IUCN (pre 1994) - Rare = RDB3 - Rare, IUCN (pre 1994) - Vulnerable = RDB2 - Vulnerable, IUCN (pre 1994) - Endangered =

Figure 1. No. of species per invertebrate group for all survey areas.

Araneae41%

Coleoptera20%

Lepidoptera10%

Hemiptera7%

Aculeata6%

Diptera4%

Orthoptera3%

Other8%

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RDB1 - Endangered. The IUCN (2001) designations are species that have been assessed using the

IUCN criteria rather 10km square distribution.

Nationally Scarce designations still use 10km square distribution for assessment of scarcity. This designation also sometimes referred to as Nationally Notable is divided into two categories. Nationally Scarce A - species found in 16 to 30 hectads (10km x 10km square), and Nationally Scarce

B - species found in between 31 and 100 hectads.

Southern restricted species are those restricted in distribution to below a line running from the Wash to the Bristol Channel, but do not have a conservation status. Some of these species may have a few outlying records further north but the great majority of records will be within this southern area of

Britain.

Widespread species are those that occur from the south coast to northern England/southern Scotland.

Universal species occur throughout Great Britain from the south coast to northern Scotland.

Heathland restricted species are those that are exclusively or predominately found on heathland and

moors. They may be found in other habitats but only rarely. These species are usually those whose foodplants are heather species or where the distinct habitat resources and physical extremes of heat, drought and acidity provided by heathland, especially southern lowland heathland are required by, or

tolerated, by these species.

Table 3. No. of species per species feeding biology.

Biology Stedham Iping (Grazed) Iping (Control) All Survey Areas

Carnivore 110 88 77 170 (59.4%)

Coprovore 2 6 1 6 (2%)

Detritivore 1 3 0 3 (1%)

Herbivore 59 41 56 80 (27.9%)

10

0

50

100

150

200

Carnivore Herbivore Nectarivore Palynivore Saproxylic Coprovore Other

All Stedham Iping (Grazed) Iping (Control)

Figure 2. No. of species per feeding biology.

Biology Stedham Iping (Grazed) Iping (Control) All Survey Areas

Nectarivore 13 20 15 24 (8.4%)

Cleptoparasite 0 2 0 2 (0.7%)

Palynivore 5 8 7 9 (3.1%)

Parasite 1 0 1 2 (0.7%)

Saproxylic 3 5 2 8 (2.8%)

Scavenger 2 1 3 4 (1.4%)

Aquatic larvae 4 1 1 4 (1.4%)

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12

0 20 40 60 80

Bare GroundBark

DungPlant Litter

Fresh waterTall Vegetation

Scrub/treesNectar/pollen

MossBirch

GorseGrasses

HeatherPine

All

StedhamIping (G

razed)Iping (C

ontrol)

Figure 3

. No

. of sp

ecies per

hab

itat resou

rce associatio

n.

Table 3. No. of species per species habitat resource association.

Habitat Resource Association

Stedham Iping (Grazed) Iping (Control) All Survey Areas

Physical, substrate & detritus resources.Physical, substrate & detritus resources.Physical, substrate & detritus resources.Physical, substrate & detritus resources.Physical, substrate & detritus resources.

Bare Ground 13 24 15 34 (11.8%)

Bark 6 1 0 7 (2.4%)

Dung 3 7 1 8 (2.8%)

Plant litter 19 13 9 25 (8.7%)

Standing fresh water

5 1 1 5 (1.7%)

Biological resources.Biological resources.Biological resources.Biological resources.Biological resources.

Tall vegetation 49 40 39 73 (25.5%)

Lower branches of scrub and trees.

41 22 23 50 (17.5%

Nectar/pollen 13 20 15 24 (8.4%)

Moss spp. 9 5 1 11 (3.8%)

Species associations (foodplants, prey, structure).Species associations (foodplants, prey, structure).Species associations (foodplants, prey, structure).Species associations (foodplants, prey, structure).Species associations (foodplants, prey, structure).

Birch 9 3 6 10 (3.5%)

Gorse 10 8 13 17 (5.9%)

Grasses 7 7 6 8 (2.8%)

Heather 26 26 23 34 (11.8%)

Pine 8 5 3 9 (3.1%)

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5.! Species AccountsDuring the survey three UK BAP species, one IUCN (2001) - Vulnerable species, two IUCN (pre 1994)

- Rare species, four Nationally Scarce A , 21 Nationally Scarce B species and one uncategorised Nationally Scarce species were recorded. Brief information about the biology and conservation of

each of these species is listed below.

Plebejus argus (Linnaeus, 1758) - Silver-studded BlueInvertebrate Group: Lepidoptera (Moths & Butterflies) - LYCAENIDAE

Conservation Status: UK BAP, IUCN (2001) - Vulnerable

Figure 4. Male and female silver-studded blue on Stedham Common.

In Britain this species is strongly associated with lowland heathland and due to the loss of this habitat over the last few decades this species has undergone a serious decline. On heathland it’s foodplants

include heather, bell heather, cross-leaved heather and Ulex spp. There is also a strong association with ants especially Lasius spp. which protect the larvae of this species in exchange of a honeydew-like substance that the larvae produce.

The species was recorded from all three survey areas during the survey. It’s continued presence at the

site seems pretty secure with current management aimed at preventing the loss of heather to scrub succession.

Asilus crabroniformis Linnaeus, 1758 - Hornet RobberflyInvertebrate Group: Diptera (Two-winged Flies) - ASILIDAEConservation Status: UK BAP, Nationally Scarce

This is the largest and most spectacular robberfly in Britain. It is scarce and declining due to the loss of it’s heathland and chalk grassland habitat and the cessation or infrequent grazing on habitat that

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remains. The adults prey on grasshoppers and dung beetles and the larvae feed on the larvae of dung

beetles. Eggs are laid under the dry crust of cow and rabbit dung, or in adjacent free-draining soil.

The species was recorded within the Iping grazing trial survey area flying around cattle dung on a sandy path. Any effort to continue and expand grazing within the reserve will benefit this species. The species has probably occurred in low numbers at Iping even when there was no grazing as it can use

rabbit dung, although the increase in dung due to cattle presence will most likely increase the population within Iping.

Dipoena inornata (O.P.-Cambridge, 1861)

Invertebrate Group: Araneae (Spiders) - THERIDIIDAEConservation Status: UK BAP, Nationally Scarce B

This scarce heathland comb-foot spider has undergone a 50% decline in distribution over the last couple of decades, this could be partly due to the difficulty of finding the species as well as the loss of

habitat. It has a specialised habitat, requiring tall mature heather or gorse overhanging bare ground where it creates sticky lines of silk attached to the ground from it’s retreat in the vegetation. Ants are the main prey item for this species and it uses this unusual ‘sticky silk fishing’ method to catch the

ants.

This small black species has a superficial resemblance to a money spider, and to another heathland specialist Dipoena tristis, both of these species were found during the survey.

Dipoena inornata was found on both Iping survey areas by beating heather and gorse beside paths. Heather and gorse bordering bare ground is key for this species so as long as mature heather and low

scrubby gorse bordering paths and scrapes is present then this species should continue to occur at the reserve.

Eutolmus rufibarbis (Meigen, 1820) - Golden-tabbed Robberfly Invertebrate Group: Diptera (Two-winged Flies) - ASILIDAEConservation Status: IUCN (pre 1994) - Rare

This impressive insect, one of the largest British robberflies is a heathland specialist and is very scarce

being found mainly on heathland areas in the New Forest, Surrey and West Sussex. It is mainly associated with grassy areas on heaths adjacent to woodland edge. It’s main prey is other Diptera and it lays it’s eggs in incisions cut into grass stems.

The species was found at Stedham and the grazing trial area at Iping during the survey. The reserve

seems ideal for this species with plentiful acidic grassland and proximity to woodland edge and the species seemed quite common and conspicuous during the survey.

Lygus pratensis Linnaeus, 1758

Invertebrate Group: Hemiptera (True Bugs) - MIRIDAE Conservation Status: IUCN (pre 1994) - Rare

This mirid bug used to be scarce and confined to southern heathland, it has recently undergone a

rapid expansion in distribution and now occurs in other semi-natural habitats in Southern Britain.

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The species was recorded within the control survey area at Iping during the survey. As this species is expanding and now not particularly associated with heathland, occurring in a number of other

habitats it very likely it will continue to occur at the reserve.

Araniella displicata (Hentz, 1847)

Invertebrate Group: Araneae (Spiders) - ARANEIDAE

Conservation Status: Nationally Scarce A

This colourful orbweaver is very scarce in Britain restricted to a small number of heathland sites in south-east England. It is associated with pine trees on heathland, where it is found on the lower branches. There are so few recent records that this species must be considered at greater risk than

many nationally rare and vulnerable species despite it only having a nationally scarce conservation status. The loss of pine trees on heathland is the greatest concern to the conservation of this species.

The species was recorded from the lower branches of pine trees at Stedham and the grazing trial survey area at Iping. As long as scattered open grown pine trees are left and pine control management

doesn’t entail a wholesale removal of pine within the site then this species should continue to occur at the site.

Zelotes petrensis (C.L.Koch, 1839)

Invertebrate Group: Araneae (Spiders) - GNAPHOSIDAE Conservation Status: Nationally Scarce A

A very scarce ground spider which until recently was mainly confined to Surrey and Hampshire. The

species occurs on dry warm sites such as heathland, chalk grassland and coastal shingle. As with many Zelotes species it is associated with bare ground, litter and stones. It is most likely a nocturnal hunter, sheltering in relatively humid micro habitats such as litter and under stones during the day.

The species was found amongst pine and heather litter under a pine tree at Stedham and is the first

record of the species for Sussex. This species most likely requires open heathland and bare ground to hunt at night but also requires humid refuges such as pine litter and stones to prevent desiccation during the day.

Dipoena tristis (Hahn, 1833)

Invertebrate Group: Araneae (Spiders) - THERIDIIDAE

Conservation Status: Nationally Scarce A

A very scarce spider confined mainly to heathland in southern England, although it has been recorded from grassland. The spider preys on ants caught in a small web made on heather, gorse and other tall

vegetation. Similar in general appearance to D. inornata but larger.

The species was recorded from heather at Stedham during the survey. This species seems to be the most common species of Dipoena on West Sussex heathlands and the presence of a varied age

structure within heather management and an abundance of its ant prey then the continued existence of this species at the reserve seems secure.

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Trypocopris pyrenaeus (Charpentier, 1825) - Heath Dumble dorInvertebrate Group: Coleoptera (Beetles) - GEOTRUPIDAEConservation Status: Nationally Scarce A

A very scarce dung beetle confined to dry heathland in southern England. The species was recorded

from the grazing trial survey area at Iping during the survey.

Formica sanguinea Latreille, 1798 - Slave-making AntInvertebrate Group: Aculeata (Bees, Ants & Wasps) - FORMICIDAEConservation Status: Nationally Scarce B

This is the only British Formica species that exhibits dulotic behaviour, stealing larvae and pupae from other Formica species, although it can exist in isolation of other Formica species. It has a very interesting disjunct distribution occurring on sandy heathland and open woodland in southern Britain

and central Scotland. It is mainly found associated with pine trees within these habitats where it is very conspicuous hunting invertebrates on the bark of pine trees and on open ground.

The species was recorded from Stedham during the survey.

Evagetes dubius (Vander Linden,1827)

Invertebrate Group: Aculeata (Bees, Ants & Wasps) - POMPILIDAEConservation Status: Nationally Scarce B

This is a scarce pompilid wasp that is strongly associated with sandy heathland in Southern Britain and

can be quite frequent within this habitat. It is a cleptoparasite of ground nesting spider-hunting wasps within Pompilidae.

The species was recorded from the grazing trial survey area at Iping during the survey.

Araneus angulatus Clerck, 1757

Invertebrate Group: Araneae (Spiders) - ARANEIDAE Conservation Status: Nationally Scarce B

Figure 5. Photo of Araneus angulatus specimen found at Lullington Heath.

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This scarce orbweaver is confined to the coastal counties of Southern Britain. It is associated with

scrub and woodland edge habitats where it can make a very large orb web in tall scrub and the lower branches of trees and attached to the ground underneath.

In Sussex the species seem to occur in three distinct areas, the west sussex heaths, Lullington Heath & the adjacent Friston Forest and in coastal scrub and woodland edge in the Rye Harbour area.

The species was recorded from Stedham during the survey.

Hypsosinga sanguinea (C.L.Koch, 1844)

Invertebrate Group: Araneae (Spiders) - ARANEIDAE

Conservation Status: Nationally Scarce BThis small scarce orbweaver is found mainly on heathland, although occasionally occurs on chalk grassland. It is mainly associated with tall heather, usually in damper areas, where it makes it small

orbweb.

The species was quite frequent and found in all three survey areas during the survey.

Zilla diodia (Walckenaer, 1802)

Invertebrate Group: Araneae (Spiders) - ARANEIDAE Conservation Status: Nationally Scarce B

Figure 6. Photo of Zilla diodia within orb web.

This small orbweaver is restricted to southern England and south-east Wales, and despite having a Nationally Scarce B designation is very common and widespread within Southern England especially the south-east. It can be found in many habitats on scrub and woodland edge, but is especially

frequent on heather within heathland.

The species was recorded from the grazing trial survey area at Iping during the survey.

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Micaria silesiaca L.Koch, 1875

Invertebrate Group: Araneae (Spiders) - GNAPHOSIDAE

Conservation Status: Nationally Scarce B

This is a very scarce ant-mimic ground spider confined to dry sandy heathland in southern Britain. During the survey it was found on bare ground created by scrapes, and was found with another scarce spider Xerolycosa nemoralis both of which obviously greatly benefit from the scrape management

carried out at Iping.

The species was recorded in both the grazing trial and control plot at Iping during the survey.

Micaria subopaca Westring, 1861

Invertebrate Group: Araneae (Spiders) - GNAPHOSIDAE

Conservation Status: Nationally Scarce B

This is a another scarce ant-mimc ground spider confined mainly to heathland in Southern Britain although this species occupies a totally different niche hunting on pine bark exposed to the sun. The species has also been recorded from oak trunks and fallen dead wood. Recent surveys of heathland in

south-east England has shown this species seems to be quite frequent on pines on heathland and the loss of open grown pine trees on heathland is the biggest threat to this species as well as the loss of

heathland habitat itself.

The species was recorded on pine trees within Stedham during the survey.

Neriene furtiva (O.P.-Cambridge, 1871)

Invertebrate Group: Araneae (Spiders) - LINYPHIIDAE

Conservation Status: Nationally Scarce B

This relatively large patterned money spider is very scarce and confined to heathland in Southern

Britain. It makes its sheet web amongst heather, especially on heather edging paths, scrapes and other open areas.

The species was swept from heather within Stedham during the survey.

Satilatlas britteni (Jackson, 1913)

Invertebrate Group: Araneae (Spiders) - LINYPHIIDAE Conservation Status: Nationally Scarce B

This is a very interesting record as this species occurs mainly on the western coast of Britian within Sphagnum bogs and saltmarsh. The species was found by sieving Sphagnum moss within Stedham and

is the first record of the species in Sussex.

Xerolycosa nemoralis (Westring, 1861)

Invertebrate Group: Araneae (Spiders) - LYCOSIDAE Conservation Status: Nationally Scarce B

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This distinctive wolf spider is confined to south-east Britain and occurs within dry heathland, chalk grassland and open woodland. It is obviously a thermophilous species and can be seen actively

hunting on bare ground on warm days. The scrape management within Iping appears to greatly benefit this species as well as Micaria silesiaca.

The species was recorded in numbers from scrapes within the grazing trial survey area at Iping and on sandy paths within Stedham.

Ero tuberculata (De Geer, 1778)

Invertebrate Group: Araneae (Spiders) - MIMETIDAE Conservation Status: Nationally Scarce B

This pirate spider is found mainly on heathland in Southern Britain, although it does occur in other

habitats. The species hunt other spiders mainly species from the Theridiidae family.

The species was found by sweeping heather within Stedham during the survey.

Figure 7. Photo of Ero tuberculata showing the four strange projections on the abdomen.

Philodromus collinus C.L.Koch, 1835

Invertebrate Group: Araneae (Spiders) - PHILODROMIDAE Conservation Status: Nationally Scarce B

This species is confined to southern and eastern England, although is quite widespread within this area. It occurs on the lower branches of pines within heathland and woodland.

The species was found by beating the lower branches of pine trees within Stedham during the survey.

Philodromus praedatus O.P.-Cambridge, 1871

Invertebrate Group: Araneae (Spiders) - PHILODROMIDAE Conservation Status: Nationally Scarce B

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This is a very difficult species to separate from closely related Philodromus species, therefore has

probably been overlooked accounting for the Nationally Scarce status. It is actually a widespread species occurring from southern England to central Scotland. It is usually associated with oak trees but

was found on pine trees with Philodromus collinus during the survey.

The species was found by beating the lower branches of pine trees within Stedham during the survey

and is the first record for Sussex.

Evarcha arcuata (Clerck, 1757)

Invertebrate Group: Araneae (Spiders) - SALTICIDAE Conservation Status: Nationally Scarce B

Figure 8. Photo of a male Evarcha arcuata.

This relatively large jumping spider is a distinctive part of the invertebrate fauna of heathland in

Southern Britain, although it has been occasionally recorded further north from moors and raised bogs. It is usually associated with the wetter areas of heathland, especially amongst Molinia beds.

It was common during the survey occurring in all three survey areas.

Marpissa muscosa (Clerck, 1757)

Invertebrate Group: Araneae (Spiders) - SALTICIDAE Conservation Status: Nationally Scarce B

This scarce, although expanding, jumping spider is the largest Salticid in Britain. It occurs mainly on

the trunks of pines and oaks, as well as fence posts, fallen dead wood and on dry stone walls. It is a thermophilous species occurring only in south-east England and actively hunts during the day.

The species was found hunting on pine bark within Stedham during the survey.

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Anelosimus aulicus (C.L.Koch, 1838)

Invertebrate Group: Araneae (Spiders) - THERIDIIDAE Conservation Status: Nationally Scarce B

This very scarce comb-foot spider is confined to heathland and coastal grasslands within southern Britain. It is found mainly on gorse within these habitats.

The species seems to be very common and numerous within the reserve occurring on gorse and

heather within all three survey areas during the survey.

Episinus truncatus Latreille, 1809

Invertebrate Group: Araneae (Spiders) - THERIDIIDAE

Conservation Status: Nationally Scarce B

This scarce comb-foot spider is also confined to heathland and coastal grassland within southern Britain. It spins it’s very unusual and minimal web, forming just a H shape supported from tall vegetation and heather and attached to bare ground.

The species was recorded from the grazing trial area of Iping during the survey.

Thomisus onustus Walckenaer, 1806 - Heather Crab SpiderInvertebrate Group: Araneae (Spiders) - THOMISIDAE Conservation Status: Nationally Scarce B

Figure 9. Photo of a female Thomisus onustus.

This very distinctive and unique looking crab spider is very restricted in Britain occurring only on sandy heathland in Southern England. It hunts mainly on the flowers of Erica tetralix and Erica cinerea,

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and can change it’s colour to match the flowers it is hunting on. It can be found on other flowers and

was found recently hunting on cotton grass within Iping Common and had changed it’s colour to a very pale, almost white, shade of pink.

The species does seem to be mainly associated with Erica tetralix within the wetter parts of heathland, so draining of heathland is probably the biggest risk to the species, as well as the loss of heathland.

The species was found in all three survey areas during the survey, but in low numbers, being most

common at Stedham.

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6.! Conclusions & DiscussionStedham & Iping Common Nature Reserve is clearly of national importance for the invertebrate

assemblages it supports, especially for it’s spider fauna. Heathland is the most speciose habitat for spiders in Britain and many rare and scarce spiders are confined to southern sandy heathland.

Stedham & Iping Common is no exception to this and is comparable to many other important heathland sites in south-east England such as West Sussex heaths Ambersham Common & Lullington Heath, and Dorset heaths such Godlingston and Studland. This is well represented in the results with

41% of all species recorded being spiders (see Figure 1). Before this survey was conducted 160 species had been recorded for the reserve, mainly due to the work of Peter Merrett in the late 1960s

and the author (Andy Phillips) in 2007. This survey has added 44 species to the list and the site now has a spider check list of 204 species which represents about 30% of the British spider fauna (see Appendix X).

The reserve is also well known for it’s Aculeate Hymenoptera and Diptera assemblages but these

where not well represented in the results. The reason for this is most probably due to the incessant cool, wet and windy weather suffered during the spring, summer and autumn of 2012. Even though dry, warm weather was chosen for the survey visits, either side of the visits the weather was inclement

and a number of survey visit attempts had to be abandoned due to the weather. This resulted in very few insects on the wing during the survey visits and Diptera and Aculeata where scarce. This resulted

in a lower number of species than expected associated with bare ground and nectar & pollen resources being recorded. The differences between the survey areas in regard to bare ground and nectar resources are still relevant despite the lower than expected sample size for these groups.

The survey was designed to compare survey areas that are grazed with a non grazed control. Stedham

has been grazed for a much longer period of time than the grazing trial in Iping. By interpreting the results in section 4 it is possible to analyse what differences and similarities occurred between the three survey areas.

Stedham Survey AreaStedham was clearly the most speciose survey area and is quite different in nature to Iping. Stedham has a more compact, less open habitat mosaic structure than Iping created by the past problems this

area has had with scrub succession. It also has more extensive areas of wet heath and open water.

Structure and ecotone within heathland plays an very important role in supporting a speciose assemblage of spiders. A large open area of even age heather can be quite poor for spiders whereas a diverse structured heathland mosaic of woodland edge, scrub, varied aged heather, acid grassland,

bare ground, open grown pines and litter can support the most species rich assemblage of spiders in Britain, and Stedham is a good example of this.

Stedham had the greatest number of species in most categories most notably with species associated with scrub and tall vegetation. (The tall vegetation category includes both herbaceous and woody

vegetation including tall heather, tall grasses and flowering plants). This category is important as it creates the structure which benefits web building spiders and Stedham had a more extensive and

diverse amount of tall vegetation habitat.

Species associated with birch and pine where highest in Stedham also reflecting the continuing

problems with the amount of scrub present with this survey area. Heathland is essentially a woodland clearing habitat and it will naturally quickly revert to scrub through to high canopy. Management

requires the balance between maintaining a high percentage of heather and heather associated

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assemblages and ensuring the structurally diverse ecotone between heathland and woodland edge is

not completely removed.

Grazing plays an very important role in creating such a habitat. Although other management methods such as removal of invasive scrub and bracken, retaining a small number of open grown pines, scrape creation, path maintenance, and heather cutting & burning are just as important as grazing and when

combined create the varied aged heather structure and dwarf scrub mosaic that produces quality heathland for invertebrates.

Stedham was also highest in species associated with wet heath resources such as open water and Sphagnum moss. This reflects the more extensive areas of wet heath present within the survey area in

comparison to the dryer more sandy nature of Iping.

Iping Grazing Trial Survey AreaThe two Iping survey areas were very similar (see Table 1), sharing 39.2% of species. There was a trend

for the grazing trial area to be slightly more speciose in most categories than the control area, but the difference is so slight it cannot be considered significant.

There were some differences though within the habitat resource association analysis between the grazing trial and control area and the Stedham survey area. The grazing trial had the highest number

of species in the bare ground, dung and nectar & pollen resource categories. The grazing trial area had the greatest abundance of bare ground and this is reflected in the results. There was also a greater

abundance of dung resource due to the cattle present grazing in the area. This resulted in a greater number of coprovores (dung eaters) recorded in this area in addition to predators associated with dung such as the hornet robberfly and the solitary wasp Mellinus arvensis which was particularly abundant

in this area on the September visit.

The reason for the grazing trial to come out top in nectar & pollen resource associated species is unclear. It’s important to consider the lack of Aculeata and Diptera on the wing during the survey dates could have resulted in an artefact in the results. Cattle will usually favour grassland when

grazing during the summer on heathland and the Deschampsia and Molinia grassland was clearly being favoured by the cattle within the grazing trial area. The grassland in this survey area was much

shorter than grassland areas in the control plot and Stedham. This shorter grassland had a greater abundance of flowering acid grassland species, predominantly tormentil and this seemed to be the only area within the survey area where Aculeates were foraging from nectar sources in addition to

heather flower foraging.

The similarities between the two Iping survey plots has produced a very interesting baseline snap shot at a very early stage in the implementation of a change in management. It would be very beneficial to keep the management of the two survey areas exactly the same except for grazing so that a repeat of

this survey could be undertaken in 5-10 years time to assess any changes brought about by grazing management over a longer time frame.

Iping Control Survey AreaThe main differences and similarities between the two Iping plots is discussed above but there was also a greater abundance of scrub associated species in the control plot, especially gorse and birch

associated species. This highlights that the control plot has a greater abundance of scrub than the grazing trial. The control plot did have one of the biggest blocks of gorse in the three survey areas and

was particularly rich in gorse associated spiders such as Anelosimus aulicus and Dipoena inornata.

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7.! ReferencesALEXANDER, K. 1986. A field key to Soldier Beetles (Coleoptera: Cantharidae). Unpublished

ALEXANDER, K. N. A. 2002. The invertebrates of living & decaying timber in Britain and Ireland - a provisional

checklist. English Nature Research Report no. 467

COLLINS, G., EDWARDS, M., HODGE, P. & PHILLIPS, A. 2006. Hastings Country Park Nature Reserve Invertebrate Survey. Hastings Borough Council.

COX, M. L. 2007. Atlas of the Seed and Leaf Beetles of Britain and Ireland. Pisces Publications

EDWARDS, R., (ed) 1998. Provisional Atlas of the aculeate Hymenoptera of Britain and Ireland. Part 2. Huntingdon: Biological Records Centre.

EDWARDS, R. & TELFER, M.G., (eds) 2002. Provisional Atlas of the aculeate Hymenoptera of Britain and

Ireland. Part 4. Huntingdon: Biological Records Centre.

HARDE, K. W. & SEVERA, F. 1999. A field guide in colour to Beetles. Blitz Editions

HARVEY, P.R., NELLIST, D.R. & TELFER, M.G. (eds) 2002. Provisional Atlas of British Spiders (Arachnida,

Araneae), Volume 1. Huntingdon: Biological Records Centre.

HARVEY, P.R., NELLIST, D.R. & TELFER, M.G. (eds) 2002. Provisional Atlas of British Spiders (Arachnida, Araneae), Volume 2. Huntingdon: Biological Records Centre.

KIRK-SPRIGGS, A. H. 1996. Pollen Beetles Coleoptera: Kateridae and Nitidulae: Meligethinae. Royal Entomological Society

LOTT, D. A. 2009. The Staphylinidae (rove beetles) of Britain and Ireland Part 5: Scaphidiinae, Piestinae,

Oxytelinae. Royal Entomological Society

LUFF, M. L. 2007. The Carabidae (ground beetles) of Britain and Ireland. Royal Entomological Society

MARSHALL, J. & OVENDEN, D. 2004. Guide to British Grasshoppers and allied insects - 2nd edition. Field

Studies Council

MORRIS, M.G., 1997. Broad-nosed Weevils Coleoptera: Curculionidae (Entiminae). Royal Entomological Society of London.

MORRIS, M.G., 2002. True Weevils (Part I) Coleoptera: Curculionidae (Subfamilies Raymondionyminae to Smicroychinae). Royal Entomological Society of London.

PLANT, W. COLIN. 1997. A key to the adults of British lacewings and their allies. Field Studies Council

ROBERTS, M. J. 1993. The Spiders of Great Britain and Ireland. Harley Books

STERLING, P., PARSONS, M. & LEWINGTON, R. 2012. Field Guide to the Micro moths of Great Britain and

Ireland. British Wildlife Publishing

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SOUTHWOOD, T. R. E. & LEESTON, D. 2005. Land & Water Bugs of the British Isles - reprint. Pisces

Conservation

STUBBS, A.E. & FALK, S. J. 2002. British Hoverflies. British Entomological and Natural History Society.

http://www.britishbugs.org.uk/ last accesed 12/11/2012

http://www.kerbtier.de/enindex.html last accesed 12/11/2012

http://www.thewcg.org.uk/idaids/ccrypticapallida.htm last accesed 12/11/2012

http://markgtelfer.co.uk/ last accesed 12/11/2012

8.! Acknowledgments

A particular thanks to Mike Edwards for providing habitat resource information and advice on invertebrate assemblage analysis.

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