Hackney Main Marsh. Click on the photo to enlarge it.

A SURVEY OF THE INVERTEBRATES OF HACKNEY MARSHES, 2007

by Neil Anderson

November 2007

CONTENTS

Introduction...... 4 Habitat Survey Map of Hackney Marshes...... 5 Methods...... 6 Species Lists: Birds...... 9 Mammals...... 9 ...... 10 Spiders...... 17 Molluscs...... 19 Isopods...... 19 Amphipoda (Sandhoppers)...... 20 General Comments...... 21 Management Suggestions...... 23

3 A SURVEY OF THE INVERTEBRATES OF HACKNEY MARSHES, 2007 by Neil Anderson

INTRODUCTION

Hackney Marshes comprise an extensive area (circa 170 hectares) of open, green land which constitutes the largest open space in the London Borough of Hackney. It forms part of the Lea Valley regional park.

This area is dominated by amenity sports turf which is much used by the local community, particularly at weekends. The sports area does not support a wide diversity of invertebrates but can contain important numbers of a limited number of species, such as earthworm species and the larvae of such insects as crane flies (Tipulidae). This limited array of invertebrates do provide an important food resource for good numbers of birds, such as wintering gulls, Carrion Crows, Magpies, Starlings and a few pairs of Mistle Thrushes. Woodpigeons also use this area for feeding on seeds.

Surrounding the football pitches are some valuable (for people and wildlife) corridors that allow a diverse range of fauna and flora to flourish.

The tidal Old River Lea borders the eastern side of the Main Marsh and has a thriving fish population with its attendant avian predators, which indicate a healthy riverine ecosystem. Cormorants, Grey Herons and Kingfishers were regularly observed fishing here and a Little Egret was seen on one occasion. Outside the main breeding season there were small numbers of duck such as Mallard, Teal, Gadwall and Tufted Duck, feeding on seeds, aquatic vegetation and invertebrates. Mute Swans, Canada and Greylag Geese, Coots and Moorhens The tidal Old River Lea forms the east boundary of Hackney Main Marsh. also eke out a living here. Grey Wagtails were observed Click on the photo to enlarge it. feeding on insects at the water’s edge.

Running along side the western perimeter is the Lea Navigation Canal – popular with boaters, walkers, cyclists and anglers. This supported a much smaller range of birds, but did have floating vegetation which provides suitable habitat for species such as the Red-eyed Damselfly, Erythromma najas. Common Frogs were also observed here.

Within the boundaries formed by these waterways is a diverse mosaic of secondary woodland, scrub and neutral grassland habitats, which were the basis for this survey. One or two visits each month were made between March to September (inclusive) during suitable weather conditions i.e. settled, not too windy, dry with at least intermittent sunshine – which wasn’t always easy with the wettest Summer on record following the sunniest, hottest recorded April. This extreme weather certainly had an impact on invertebrate numbers, particularly the prolonged wet periods

4 HACKNEY MARSHES: SURVEY OF HABITATS

VIEW ENLARGED MAP

5 METHODS

This invertebrate survey used four methods for detecting the species using the survey area:

1 Direct observation – particularly for conspicuous mobile insects such as butterflies, dragonflies and bumble bees. 2 Turning over dead wood and other debris – revealing taxa such as woodlice and molluscs as well as certain spiders and . 3 Beating Tray – this was used for systematically beating the foliage of shrubs, lower branches of trees, and stout herbaceous plants. 4 Sweep Net – for sweeping invertebrate denizens of grass/herb communities.

The following taxa were identified and recorded – all species of the following groups: Odonata, Orthoptera, butterflies and macro-moths (as well as a few distinctive micro- moths), shieldbugs and their allies, Coccinellidae, social Hymenoptera and Isopoda, as well as a good range (but not exhaustive) of Coleoptera, Syrphidae, spiders, molluscs, and a few distinctive species of other groups.

The survey was conducted by dividing the site into six agreed habitat areas, which are coded from numbers 1 to 6 in the invertebrate list below; the presence in each zone is indicated by a + symbol. The six zones are as follows:

1 A linear walk of over 1 km along the Old River Lea, from the bridge across to East Marsh north to Friends’ Bridge, bordered by the water to the East and a tarmac path to the West. Early in the season, the river-edge mud was much exposed; but as the season progressed, it was swamped by the vigorous, alien annual Himalayan Balsam, Impatiens glandulifera, which then formed a near monoculture. An attractive if not particularly welcome plant – few if any invertebrates seemed to feed on its leaves, although the nectar-rich flowers were relished by some bees. Another dominant alien along the river, in slightly drier areas, is the Russian Comfrey, Symphytum x uplandicum, which is similarly used by invertebrates primarily as a nectar source.

The walk is principally through secondary woodland, in which poplar, Populus, and willow, Salix, species are dominant, although a wide variety of other native and exotic trees are also present. Shrubs include Elder, Sambucus nigra and some Prunus species.

The ground flora isn’t particularly diverse and indicates a nutrient-rich soil. In the Spring, the area looks attractive with the massed umbels of Cow Parsley, . Though not the most productive of plants for insects, it supported populations of two Notable species of – the , Phyoecia cylindrica (one of two species of longhorn beetle in the UK that use non-woody plants); and the leaf beetle, Chrysolina oricalcia.

Nettles, Urtica dioica, are a dominant part of the field layer and support a wide range of fauna, including: snails; larvae of vanessid butterflies and various moths, such as Mother of Pearl and Angle Shades; aphids, which support aphidophagous insects, such as some hoverfly larvae and ladybirds; weevils, such as Phyllobius pomaceus; various bugs, such as Heterotoma planicornis and Calocoris stysi; not to mention a hunting ground for spiders. The Nursery Web Spider, Pisaura mirabilis, was seen in some numbers basking on these ubiquitous plants.

6 Other widespread herbs included: Goosegrass [or Common Cleavers], Galium aparine; Burdock, Arctium minus; and Hogweed, .

Dead wood piles are another useful micro-habitat in this zone, providing shelter and/or food for as diverse as woodlice, earthworms, molluscs and spiders. The biggest surprise turning over some wood in the wettest areas were numbers of the introduced Australian amphipod, Arcitalitrus dorrenei, which is the only UK terrestrial species. Known mainly in parts of south-west England, it has been recorded in the London area in places such as Kew Gardens.

2 This zone runs parallel to Zone 1 to the West of the tarmac path. The habitat is similar to the drier parts of Zone 1, though with a slightly more diverse flora, and incorporates the areas known as North and East Woods. To the inside of this zone are some small mini-meadows with saplings, which hold various grassland species otherwise absent from this zone, such as Roesel’s Bush-cricket, Metrioptera roeselii, and Bishop’s Mitre, Aelia acuminata. Survey Zone 2. Click on the photo to enlarge it. A range of shrubs can be found growing here, including: Spindle, Euonymus europaeus; Gorse, Ulex europaeus; Holly, Ilex aquifolium; and Apple, Malus, species.

A variety of herbs were flowering in sunny edges, including: White Dead-nettle, Lamium album; Black Horehound, Ballota nigra; Cut-leaved Cranesbill, Geranium dissectum; and Common Mallow, Malva sylvestris.

The woodlands of Zones 1 and 2 provide breeding habitat for a range of breeding birds, such as Sparrowhawk, Stock Dove, Green and Great-spotted Woodpecker, three species of tit, and Blackcap.

3 Meadow – this area is situated at the northern end of the site, between Friends’ and Cow Bridges, and with electricity pylons within the area fenced off for security. This contains a mix of meadow grasses, such as: Cocksfoot, Dactylis glomerata; bents, Agrostis spp.; and less- welcome False Oat Grass, Arrhenatherum elatius. A wide selection of forbs [non-woody plants other than grasses, sedges and rushes] include: Black Knapweed, Centaurea nigra; Ox-eye Daisy, Leucanthemum vulgare; Wild Carrot, ; Salad Burnet, Sanguisorba minor; Field Scabious, Knautia arvensis; and Bird’s-foot Trefoil, Lotus corniculatus.

Given its sheltered and sunny position, this is one of the richest areas for life, with a good mix of grasshoppers, bush-crickets, mirid bugs, flower-visiting butterflies, hoverflies and bees. A few ant-hills are present, which are also appreciated by the local Green Woodpeckers.

The meadow is managed by an annual mow.

4 Scrub belt behind meadow (Zone 3), comprising a variety of native shrubs including: Hawthorn, Crataegus monogyna; Blackthorn, Prunus spinosa; Wild Cherry, P. avium; Hazel, Corylus avellana; Field Maple, Acer campestre; and Elder, Sambucus nigra. This scrub is pretty dense, providing cover for birds, small mammals and invertebrates. At the southern base is some low scrub, such as Bramble, Rubus fruticosus agg. † and some coarse grass/herb vegetation.

7 5 NUFU Wood * – an interesting mosaic of rough grassland with ant-hills; scrub – including a good quantity of Gorse and some Broom, Cytisus scoparius; saplings; and some maturing Oaks, Quercus robur, some Silver Birch, Betula pendula and Aspen, Populus tremula.

The young Oaks support a small number of Purple Hairstreaks. The Gorse also supports some interesting insects, including weevils such as Exapion ulicis, and the handsome Gorse Shieldbug, Piezodorus lituratus. It is a testimony to the ability of these specialist insects to disperse that they can colonise such isolated bushes.

In the tussocky grassland can be found the Wasp Spider, Argiope bruennichi – a recent arrival which specialises in capturing orthopterans in its low, distinctive web. The Long-winged Conehead, Conocephalus discolor, is another fairly recent colonist.

The sheltered nature of NUFU combined with its openness to sunshine makes it popular with insects, such as nectaring butterflies, as well as hunting/basking dragonflies.

6 Old car park – the most artificial of the zones, with much tarmac remaining, a line of young London Planes, Acer x hispanica, and some regularly-strimmed sward. To the back is a solid belt of trees and shrubs, including some large Buddleja davidii and plentiful Brambles – the latter appreciated by the human gatherers as much as the wildlife! Both species provide much nectar to a wide range of pollinating insects.

Around the edges are various ruderal weeds that thrive in brownfield-type locations, such as: Hoary Mustard, Hirschfeldia incana; Guernsey Fleabane, Conyza sumatrensis; and Barren Brome, Anisantha sterilis.

The extra warmth provided by the hard surface allows species that favour a well-drained habitat, such as Field Grasshoppers, Chorthippus brunneus, to thrive.

* NUFU = National Urban Forestry Unit: NUFU put money into the planting of trees. The idea to was to have somewhere in the London area to show people what could be done on reclaimed sites such as coal tips.

8 SPECIES LISTS

BIRDS

Whilst conducting the invertebrate survey, all birds seen on the site were recorded. Below follows the list of species found using the site.

Mute Swan Wren Greylag Goose Dunnock Canada Goose Robin Gadwall Blackbird Teal Song Thrush Mallard Redwing Tufted Duck Mistle Thrush Cormorant Reed Warbler Little Egret Blackcap Grey Heron Lesser Whitethroat Sparrowhawk Common Whitethroat Kestrel Chiffchaff Moorhen Willow Warbler Coot Goldcrest Black-headed Gull Long-tailed Tit Common Gull Blue Tit Lesser Black-backed Gull Great Tit Herring Gull Jay Common Tern Magpie Stock Dove Jackdaw Woodpigeon Carrion Crow Feral Pigeon Starling Swift House Sparrow Kingfisher Chaffinch Green Woodpecker Greenfinch Great Spotted Woodpecker Goldfinch Meadow Pipit Linnet Grey Wagtail Reed Bunting

MAMMALS

Three species of mammal were observed during visits – all widespread species. Longworth trapping would give an indication of small mammals utilising the site such, as mice, voles and shrews. Work with a bat-detector would give an insight to the species of bat using the site for foraging, breeding or roosting.

Fox Brown Rat Grey Squirrel

9 INSECTS

Odonata (Dragonflies/Damselflies)

Zygoptera (Damselflies)

Calopterygidae

Zone 1 2 3 4 5 6 Calopteryx splendens Banded Demoiselle + +

Coenagrionidae

Zone 1 2 3 4 5 6 Enallagma cyathigerum Common Blue Damselfly + + + + Ischnura elegans Blue-tailed Damselfly + + Erythromma najas * Red-eyed Damselfly

Anisoptera (Dragonflies)

Aeshnidae

Zone 1 2 3 4 5 6 Aeshna cyanea Southern Hawker + + A. mixta Migrant Hawker + + Anax imperator Emperor + +

Libellulidae

Zone 1 2 3 4 5 6 Orthetrum cancellatum Black-tailed Skimmer + + + + Sympetrum striolatum Common Darter + + + + + S. sanguineum Ruddy Darter + +

Orthoptera (Grasshoppers/Bush-crickets)

Acrididae (Grasshoppers)

Zone 1 2 3 4 5 6 Chorthippus brunneus Field Grasshopper + C. parallelus Meadow Grasshopper + + + C. albomarginatus Lesser Marsh Grasshopper +

Tettigoniidae (Bush-crickets)

Zone 1 2 3 4 5 6 Leptophyes punctatissima Speckled Bush-cricket + + + + Meconema meridionale Southern Oak Bush-cricket + + + + Conocephalus discolor Long-winged Conehead + + + Metrioptera roeselii Roesel’s Bush-cricket + + + + +

10 Dermaptera (Earwigs)

Zone 1 2 3 4 5 6 Forficula auricularia Common Earwig + + + + + +

Hemiptera (True Bugs)

Only the shieldbugs and their allies were comprehensively recorded for this order plus a few select bugs from other families.

Acanthosomatidae

Zone 1 2 3 4 5 6 Acanthosoma haemorroidale Hawthorn Shieldbug + Cyphostethus tristriatus Juniper Shieldbug +

Scutelleridae

Zone 1 2 3 4 5 6 Eurygaster testudinaria Tortoise Bug +

Cydnidae

Zone 1 2 3 4 5 6 Tritomegas bicolor Pied Shieldbug +

Pentatomidae

Zone 1 2 3 4 5 6 Aelia acuminata Bishop’s Mitre + + + + Eysacoris fabricii Woundwort Bug + + Palomena prasina Common Green Shieldbug + + + + Dolycoris baccarum Sloe Bug + + + Piezodorus lituratus Gorse Shieldbug + Eurydema oleracea Brassica Bug + +

Coreidae

Zone 1 2 3 4 5 6 Coreus marginatus Dock Bug + + +

Rhopalidae

Zone 1 2 3 4 5 6 Rhopalus subrufus +

11 Miridae (Mirid/Capsid/Grass Bugs)

Zone 1 2 3 4 5 6 Deraeocoris ruber + + Miris striatus + + Calocoris stysi + + Lysocoris pabulinus + Heterotoma planicornis +

Lepidoptera (Butterflies/Moths)

Pieridae

Zone 1 2 3 4 5 6 Pieris rapae Small White + + + + P. napi Green-veined White + + P. brassicae Large White + + + Anthocharis cardamines Orange Tip + Gonepteryx rhamni Brimstone + +

Nymphalidae

Zone 1 2 3 4 5 6 Vanessa atalanta Red Admiral + + + V. cadui Painted Lady + Aglais urticae Small Tortoiseshell + + Inachis io Peacock + + + + Polygonia c-album Comma + +

Satyridae

Zone 1 2 3 4 5 6 Parage aegeria Speckled Wood + + + + Pyronia tithonus Gatekeeper + Maniola jurtina Meadow Brown + + + + + + Coenonympha pamphilus ** Small Heath

Lycaenidae

Zone 1 2 3 4 5 6 Neozephyrus quercus Purple Hairstreak + Lycaena phlaeas Small Copper + Polyommatus icarus Common Blue + + Celastrina argiolus Holly Blue + + +

12 Hesperiidae

Zone 1 2 3 4 5 6 Thymelicus sylvestris Small Skipper + + + + T. lineola Essex Skipper + + Ochlodes venata Large Skipper + +

Hepialidae

Zone 1 2 3 4 5 6 Hepialus lupulinus Common Swift +

Zygaenidae

Zone 1 2 3 4 5 6 Zygaeana lonicerae Narrow-bordered + + 5-spot Burnet

Geometridae

Zone 1 2 3 4 5 6 Idaea aversata Riband Wave + Camptogramma bilineata Yellow Shell + +

Notodontidae

Zone 1 2 3 4 5 6 Orgyia antiqua Vapourer + +

Arctiidae

Zone 1 2 3 4 5 6 Tyria jacobaeae Cinnabar +

Noctuidae

Zone 1 2 3 4 5 6 Phlogophora meticulosa Angle Shades + Hypena proboscidalis Snout + Callistege mi Mother Shipton + Euclidia glyphica Burnet Companion + + +

Incurvariidae

Zone 1 2 3 4 5 6 Nemophora degeerella +

13 Pyralidae

Zone 1 2 3 4 5 6 Eurrhypara hortulata Small Magpie + Pleuroptya ruralis Mother of Pearl + + + Myelois circumvoluta +

Pterophoridae

Zone 1 2 3 4 5 6 Pterophorus pentadactyla + Emmelina monodactyla +

Gracillariidae

Zone 1 2 3 4 5 6 Cameraria ohridella Horse Chestnut Leaf-miner +

Diptera

Syrphidae (Hoverflies)

Zone 1 2 3 4 5 6 Syrphus ribesii + Epistrophe eligans + + Episyrphus balteatus Marmalade Fly + + + Dasysyrphus albostriatus + Sphaerophoria scripta + Volucella zonaria + + V. inanis + V. pellucens + Eristalis tenax + + E. interruptus + + + E. arbustorum + + Myathropa florea + +

Bombyliidae (Beeflies)

Zone 1 2 3 4 5 6 Bombylius major +

Hymenoptera (Bees, Ants, Wasps)

Formicidae (Ants)

Zone 1 2 3 4 5 6 Lasius niger + + + L. brunneus + L. flavus + + Myrmica ruginodis +

14 Vespidae (Social Wasps)

Zone 1 2 3 4 5 6 Vespula vulgaris Common Wasp + + + + +

Anthophoridae

Zone 1 2 3 4 5 6 Anthophora plumipes + +

Apidae

Zone 1 2 3 4 5 6 Apis mellifera Honey Bee + + + + + + Bombus terrestris Buff-tailed Bumble Bee + + + + + + B. lucorum White-tailed Bumble Bee + B. hortorum Garden Bumble Bee + + B. pascuorum Common Carder Bee + + + + + +

Coleoptera (Beetles)

Carabidae (Ground Beetles)

Zone 1 2 3 4 5 6 Paranchus albipes + Demetrias atricapillus + + Nebria brevicollis + Pterostichus madidus +

Staphylinidae (Rove Beetles)

Zone 1 2 3 4 5 6 Tachyporus hypnorum + + +

Cantharidae (Soldier Beetles)

Zone 1 2 3 4 5 6 Cantharis rustica + C. fusca + + + Rhagonycha fulva + + + +

Melyridae

Zone 1 2 3 4 5 6 Malachius bipustulatus + +

15 Coccinellidae (Ladybirds)

Zone 1 2 3 4 5 6 Subcoccinella 24-punctata 24-spot Ladybird + + + + + Exochomus quadripustulatus Pine Ladybird + + Tytthaspis 16-guttata 16-spot Ladybird + Adalia bipunctata 2-spot Ladybird + + + + + A. 10-punctata 10-spot Ladybird + + + Coccinella 7-punctata 7-spot Ladybird + + + + + + Harmonia axyridis Harlequin Ladybird + + + + + + Propylea 14-punctata 14-spot Ladybird + + + + Halyzia 16-guttata Orange Ladybird + + + Psyllobora 22-punctata 22-spot Ladybird + + + + +

Oedemeridae

Zone 1 2 3 4 5 6 Oedemera nobilis + + + + + O. lurida + + + +

Tenebrionidae (Darkling Beetles)

Zone 1 2 3 4 5 6 Isomira murina +

Scarabaeidae (Scarabs/Chafers)

Zone 1 2 3 4 5 6 Cetonia aurata Rose Chafer +

Lucanidae

Zone 1 2 3 4 5 6 Dorcus parallelipipedus Lesser Stag Beetle +

Cerambycidae (Longhorns)

Zone 1 2 3 4 5 6 Grammoptera ruficornis + + cylindrica + + Strangalia melanura + Pseudovadonia livida + +

16 Chrysomelidae (Leaf Beetles)

Zone 1 2 3 4 5 6 Chrysolina oricalcia + Crepidodera aurea + + Cassida vibex + C. rustica + Podagrica fuscicornis +

Curculionidae (Weevils)

Zone 1 2 3 4 5 6 Rhynchites aequalis + Phyllobius argentatus + + P. pomaceus + Dorytoma longimanus + Curculio glandium + Hypera rumicis + Sitona striatella + S. lineatus + Cutorhynchus pollinarius +

Apionidae (Weevils)

Zone 1 2 3 4 5 6 Exapion ulicis + + Apion frumentarium + +

SPIDERS

Dictynidae

Zone 1 2 3 4 5 6 Dictyna arundinacea +

Dysderidae

Zone 1 2 3 4 5 6 Dysdera crocata Woodlouse-eating Spider +

Clubionidae

Zone 1 2 3 4 5 6 Clubiona reclusa + + + C. terrestris +

17 Thomisidae (Crab Spiders)

Zone 1 2 3 4 5 6 Xysticus cristatus + + + + Misumena vatia + +

Philodromidae

Zone 1 2 3 4 5 6 Philodromus cespitum + + + + P. dispar + Tibellus oblongus + +

Salticidae (Jumping Spiders)

Zone 1 2 3 4 5 6 Salticus scenicus Zebra Spider +

Lycosidae (Wolf Spiders)

Zone 1 2 3 4 5 6 Trochosa ruricola + Pardosa amentata + + + P. pullata + + +

Pisauridae

Zone 1 2 3 4 5 6 Pisaura mirabilis Nursery Web Spider + + + +

Theridiidae

Zone 1 2 3 4 5 6 Theridion sisyphium + T. varians + T. pictum + + Enoplognatha ovata + +

Tetragnathidae

Zone 1 2 3 4 5 6 Metallina segmentata + + Tetragnatha extensa + + + + T. montana + +

18 Araneidae (Orb-web Spiders)

Zone 1 2 3 4 5 6 Larinioides cornutus + Araniella cucurbitina agg. † + + + + Gibbaranea gibbosa Agalenatea redii + [Mangora acalypha TO BE CONFIRMED + ] Araneus diadematus Garden Orb-web Spider + + + + + Argiope bruennichi Wasp Spider +

Linyphiidae (Money Spiders)

Zone 1 2 3 4 5 6 Linyphia hortensis + L. triangularis + + + Neriene peltata + Gongylidium rufipes + +

MOLLUSCS

Arionidae (Round-backed Slugs)

Zone 1 2 3 4 5 6 Arion ater Large Black/Red Slug + + A. hortensis Garden Slug + A. subrufus Dusky Slug +

Agriolimacidae

Zone 1 2 3 4 5 6 Deroceras reticulatum Field Slug + +

Milacidae

Zone 1 2 3 4 5 6 Tandonia budapestensis Budapest Slug +

Zonitidae

Zone 1 2 3 4 5 6 Vitrea crystallina + Aegopinella nitidula +

19 Helicidae (Snails)

Zone 1 2 3 4 5 6 Monacha cantiana Kentish Snail + + + + + + Cepaea nemoralis Brown-lipped Snail + + + + C. hortensis White-lipped Snail + Helix aspersa Garden Snail + +

ISOPODS (Woodlice)

Trichoniscidae

Zone 1 2 3 4 5 6 Trichoniscus pusillus Common Pygmy Woodlouse +

Oniscidae

Zone 1 2 3 4 5 6 Oniscus asellus Common Shiny Woodlouse +

Philoscidae

Zone 1 2 3 4 5 6 Philoscia muscorum Common Striped Woodlouse + +

Porcellionidae

Zone 1 2 3 4 5 6 Porcellio scaber Common Rough Woodlouse +

Armadillidiidae

Zone 1 2 3 4 5 6 Armidillidium vulgare Common Pill Woodlouse + +

AMPHIPODA (Sandhoppers)

Talitridae

Zone 1 2 3 4 5 6 Arcitalitrus dorrieni +

† agg. = aggregate microspecies * Red-eyed Damselfly – small numbers recorded on adjacent Lea Navigation channel ** Small Heath recorded flying low from grass of Friends’ Wood to the sports turf and briefly settling.

20 GENERAL COMMENTS

A total of seven species of Odonata was recorded and these were widespread species. Probably the most important species is the Banded Demoiselle, Calopteryx splendens, which breeds in the Old River Lea and is found in good numbers in adjacent areas. This species mainly breeds in slow moving rivers.

The meadow areas with adjacent scrub provide a good feeding area and shelter for the darter and hawker species recorded, which may have originated locally but, being very mobile, may have come from farther afield.

Meadow Grasshopper was the only widespread grasshopper on site and was numerous in the meadows. The other two species were found only in low numbers but, given the wet Summer, may prove to be more numerous in better seasons, as Orthoptera are generally sun-loving insects.

Two formerly-rare bush-crickets – both Notable species: Roesel’s Bush-cricket and Long- winged Conehead – have undergone a dynamic expansion in the last 15 years or so and are present in good numbers in the grassland areas. Both are now widespread in the London area in suitable habitat.

Probably the most surprising discovery of this survey was a large, previously-unrecorded, colony of the recently-naturalised Southern Oak Bush-cricket, Meconema meridionale, on Hackney Marshes. This species was first recorded in the UK in the early Autumn of 2001 at Thames Ditton, Surrey and also nearby in Carshalton. Since the initial sightings, further colonies of this species have been found in the London area. Last year Roger Hawkins and I identified a colony on Wandsworth Common during a London Natural History Society field trip.

This species has been expanding its range on the near continent but, being flightless, will not have arrived here without assistance. It is likely that this species has hitched on vehicles from the continent and has since successfully colonised. From July onwards, I regularly caught circa 50 from beating the foliage of a wide range of deciduous trees and shrubs; no species specificity was shown and it occurred on tiny saplings as well as mature trees/shrubs. Given the number found from a relatively small number of beatings, I would extrapolate that the population must have been in thousands at the site, so must have been present for at least a few years. It is probably the largest known colony in the UK. It is not Southern Oak Bush-crickets: thought that this species poses a threat to native species, but it female (top) and male (above) will be fascinating to follow its status over the coming years. Click on a photo to enlarge it.

I photographed the species and sent the evidence to Dr Peter Sutton at the Orthoptera Recording Scheme, and the record was duly published in British Wildlife (2007) Vol 19 (1) p 55.

Hackney Marshes supports a diverse array of shieldbugs, including the aforementioned Gorse Shieldbug, in good numbers in NUFU Wood. The declining Pied Shieldbug, Tritomegas bicolor, was a nice find on White Dead-nettle, Lamium album. Perhaps the most notable find was a final instar Tortoise Bug, Eurygaster testudinaria, in a meadow area. This is another species that has been spreading northwards in recent years and a new arrival in Middlesex.

21 A total of 21 butterfly species using the site was impressive. 2007 wasn’t a classic year for insect migration, but Red Admirals, Vanessa atalanta, and small numbers of Painted Lady, V. cardui, were still recorded. I suspect in a “good” year, Clouded Yellows, Colias croceus, would also occur – possibly breeding.

I was pleased to find a couple of Purple Hairstreaks, Neozephyrus quercus, around the Oaks in NUFU wood, which suggests a small colony that was unrecorded in the 2004 survey, although it could easily have been overlooked.

It was rewarding to find singletons of two declining London species, the Small Heath, Ceonympha pamphilus, and Small Copper, Lycaena phlaeas. Hopefully this indicates that a small population of both these species is surviving at the site. Future monitoring will assess the status of these species. Both species are partial to nectaring at Ragwort, Senecio jacobaea, a plant useful to many invertebrates. Small Copper on Ragwort. Given that there is no stock grazing the site, Click on the photo to enlarge it. some of this plant should be left.

Brimstones, Gonepteryx rhamni, were seen in small numbers during the Spring, but these butterflies can travel some distance away from breeding areas, so it was satisfying to find proof of breeding on Hackney Marshes when a late instar larva was discovered on a leaf of Alder Buckthorn, Frangula alnus.

A reasonable number of day-flying moths were recorded, but some dedicated moth trapping would be required to get a real idea of the moth fauna of the site, of which I barely scratched the surface with casual observations.

The number and variety of hoverflies seen was disappointing, but this was not a reflection of the site, as it has generally been a poor year for them in London due to the effects of the weather. It was good to see a small number of our largest hoverfly – a Notable species, Volucella zonaria – which particularly liked the flowers of Giant Hogweed, Heracleum mantegazzianum. A Rose Chafer, Cetonia aurata, was also observed on this notorious, exotic umbellifer. Interestingly, the authors of the previous invertebrate survey (2004) commented that it was the first time they had seen this attractive beetle in the UK, though it isn’t supposed to be that rare; yet this specimen seen during my survey was also the first I had seen in the country!

As mentioned before, two Notable beetle species were discovered – Phytoecia cylindrica and Chrysolina oricalcia – that are dependent on Cow Parsley, which is abundant in the woods. Lesser Stag Beetle, Dorcus parallelipipedus, is a beneficiary of the policy to leave log piles on site, as the larvae of this beetle feed on the decaying timber.

Ten species of ladybird were recorded. A relatively new arrival to the UK is the Harlequin Ladybird, Harmonia axyridis, which was first discovered in Essex in 2004. This is a Central Asian species that was introduced into Europe and the US as a biological control for aphids. In the US, at least, it has gone on to be a pest in causing a decline in native species of ladybird and invading homes in large numbers in the Autumn.

22 Harmonia axyridis has multiplied at a dramatic rate since its initial arrival in the UK and was the most numerous ladybird recorded during the survey and recorded on every visit. It remains to be seen whether this aggressive competitor will have an adverse effect on our native species.

Good numbers of two grassland species – the 16-spot Ladybird, Tytthaspis 16-punctata, and 24-spot Ladybird, Subcoccinella 24-punctata – were located within the grass sward. With a wet Summer, both mildew-feeding species – the 22-spot Ladybird, Thea 22-punctata, and the increasing Orange Ladybird, Halyzia 16-guttata – seem to be prospering too.

Whilst observing bumble bees, I was surprised not to find any Red-tailed Bumble Bees, Bombus lapidarius, during the survey. This is a widespread species which is supposed to be one of the “common” six species; though I did note that I generally saw few of this species this season – perhaps a victim of the extreme weather?

Amongst the spiders recorded, the most notable – and one of the most distinctive – was the Wasp Spider, which was found in the tussocky grassland in NUFU Wood. This species is basically of Mediterranean origin and was first found on the south coast around 1940. During the last decade, it has been making leaps in its distribution as it spreads North, probably due to warming temperatures. It has been established in the London area for around five years now and is becoming widespread in suitable grassland.

MANAGEMENT SUGGESTIONS

In the woods, to continue leaving dead timber – log piles are best situated in partial shade. Where possible, this is best left in situ; but, where this is not feasible, it can be left in piles to support a diverse fauna. Standing dead trees should be allowed where there are not public safety concern,s as these can support a separate suite of dead-wood fauna to that on the ground.

A number of small scalloped grasslands are present to the football-pitch side of the eastern woods, some of which contain new saplings. It would be beneficial to maintain some areas as grass/herb communities, as a good variety of grassland invertebrates were discovered in them. Perhaps a narrow strip of unmown grassland can be left on the sports-field side of the wood. Sheltered, sunny, edge habitats often support a greater diversity of invertebrates than deeper in the wood. The central ride (either side of the tarmac path) should be kept fairly open, with grass/herb communities leading to brambles, and other low bushes leading into mature trees.

The North Meadow has a diverse flora, but there are a few problems arising. One or two plants of flowering Greek Dock, Rumex cristatus, were seen here and need to be removed (hand wipe with glyphosate) or they will seed through this area and form extensive stands, which is undesirable here.

In parts there is a dominance of the coarse False Oat Grass, Arrhenatherum elatius, responding to excess nutrients, which will out-compete more desirable herbs and grasses. Perhaps areas dominated by this species can be annually cut in late Spring at a height of 15cm and all cuttings removed.

For the remainder of the meadow, I would suggest cutting about 50% of the area in Year 1 and then cutting the other 50% in Year 2, so that there is always an area of long grass and seedheads, which provides a refuge for invertebrates to complete life cycles – as well as shelter for small

23 mammals and feeding opportunities for birds. It is important that all cuttings are removed from the area, to reduce fertility and prevent certain nutrient-hungry, aggressive species from dominating the meadow – which will result in a loss of floral diversity, which in turn will result in a poorer invertebrate community.

The scrub area behind North Meadow will need to be controlled to maintain a more open area of coarse grass/herbs at the front, which is a refuge for species from the meadow as well as supporting a few other species. Brambles are very useful but must not be allowed to totally dominate this area, so some periodic control will be necessary.

NUFU Wood is a superb mosaic habitat that will lose its diversity if a closed canopy develops. As saplings mature, I would recommend selective thinning to maintain an open character and allow plenty of sunshine to this area. The Gorse bushes should be managed by selective pruning to maintain a varied age structure and prevent bushes becoming overmature. At present, these are supporting some interesting insects. Again, the tussocky nature of this site along with ant-hills, dead seed-heads etc, all contribute to the diversity of this area.

The old car park has some productive scrub to the back which should be retained. The manicured area below the London Planes is fairly sterile for wildlife. This could be left unstrimmed to allow a ruderal community to develop and more invertebrates to colonise. If possible, it would be good to get some tarmac loosely drilled and allow it to revert to a potentially interesting brownfield community.

Regular monitoring of species will allow changes in status to be evaluated. We are living in rapidly changing times, when new insects are arriving – either naturally or indirectly through human activity – and some are colonising rapidly. Conversely, some familiar species are becoming much scarcer, so our fauna and flora are in a dynamic phase, some of which is fuelled by subtle climatic changes.

Contact Details To comment on this report or to add further records: Visit: www.hackneyenvironment.org.uk/HM and follow the link “Submitting Records” Email: [email protected] Phone: 07758 326530

Neil Anderson, BSc (Hons) Plant Biology 52 Beechwood Avenue, Greenford, Middlesex, UB6 9UB [email protected]

Footnote It is hoped to rediscover two spider species of the genus Xysticus, for which field identification was not sufficient for the records to be accepted, and to carry out microscopic identification. If confirmed, the records will be added to the list under Thomisidae (Crab Spiders). 29/01/2008

HMUG wish to thank Team Hackney and Hackney Parks Department for funding this survey.

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