The amazing spiders of Graffham Common

Posted by Graeme Lyons , Friday, 5 January 2018 15:42

I have just finished all the identifications from the invertebrate survey I carried out at Graffham Common this year (a total of 412 species recorded) and thought I would do a little review of the spiders. It came as quite a surprise to me that 16 of the 80 species of spider recorded during the six visits last year have conservation status! That's a remarkable 20%! I have never recording anything like this, especially as I always thought the conservation statuses for spiders were more stringent than for other taxa. Of these 16, 13 are considered nationally scarce while the remaining three are nationally rare! And when you think it was mostly conifer plantation five years ago with some tiny patches of heath you really start to see how special the site is.

Overall we have now recorded 141 spiders at Graffham. I carried out some pitfalls back in 2009 and in 2014 and we added some interesting species back then. Including Xysticus luctuosus (we had quite a few in 2009 but none in 2014). Interestingly it took me until 2017 to find a living one and only then was it one individual (the female above recorded on Fir Toat)! Back in 2009 and even earlier last year this spider wasn't classified as having any conservation status at all but now I'm please to see it's classified as nationally rare and IUCN Endangered! This spider is currently not known from anywhere else in Sussex!

But the biggest surprise for me was the gorgeous IUCN Vulnerable Uloborus walckenaerius. It's an odd looking beast and is also rare. In Sussex known from neighbouring Ambersham Common. It was well established  on Graffham West and on the last visit we even picked one up from Gallows Pond.

And also the BAP IUCN Near Threatened Lichen Running-spider Philodromus margaritatus. In Sussex known only from here and the adjacent Lavington Common. During this survey the spider was recorded on all three blocks.

We recorded for an hour on each of three blocks: Graffham West, Gallows Pond and Fir Toat. A site list was made for each of the sub-sites over the six visits. The full species list is shown below.

Species Fir Toat Gallows  West Cons status

Achaearanea riparia 1 NS
Agalenatea redii 1
Agelena labyrinthica 1 1
Amaurobius fenestralis 1
Anelosimus aulicus 1 NS
Anelosimus vittatus 1 1 1
Araneus angulatus 1 NS
Araneus diadematus 1 1 1
Araneus quadratus 1
Araniella cucurbitina 1 1 1
Araneus sturmi 1 1
Arctosa leopardus 1
Arctosa perita 1 1
Argyroneta aquatica 1
Ballus chalybeius 1 NS
Bianor aurocinctus 1 NS
Clubiona trivialis 1
Diaea dorsata 1
Dictyna arundinacea 1 1
Dictyna latens 1 1
Dipoena tristis 1 NS
Drassodes cupreus 1
Drassyllus pusillus 1
Enoplognatha latimana 1 1
Enoplognatha ovata 1 1 1
Ero tuberculata (above) 1 1 NS
Evarcha arcuata 1 1 NS
Evarcha falcata 1 1 1
Gibbaranea gibbosa 1 1 1
Harpactea hombergi 1
Heliophanus cupreus 1 1 1
Heliophanus flavipes 1
Larinioides cornutus 1
Lathys humilis 1
Linyphia triangularis 1 1 1
Mangora acalypha 1 1 1
Marpissa muscosa 1 1 1 NS
Metellina mengei 1 1 1
Metellina segmentata 1 1 1
Misumena vatia 1 1 1
Neon reticulatus 1 1
Neottiura bimaculatum 1
Nuctenea umbratica 1 1
Pachygnatha degeeri 1
Paidiscura pallens 1
Pardosa nigriceps 1
Pardosa palustris 1 1
Pardosa pullata 1 1
Pardosa saltans 1 1 1
Philodromus albidus 1 1
Philodromus aureolus 1 1
Philodromus cespitum 1
Philodromus dispar 1 1 1
Philodromus margaritatus 1 1 1 NR
Philodromus praedatus 1
Pirata latitans 1
Pisaura mirabilis 1 1 1
Rugathodes instabilis 1 NS
Salticus cingulatus 1
Salticus zebraneus 1 NS
Savignia frontata 1
Simitidion simile 1 1 1
Stemonyphantes lineatus 1
Tegenaria silvestris 1
Tetragnatha nigrita 1 1
Tetragnatha obtusa 1
Tetragnatha pinicola 1
Theridion impressum 1
Theridion sisyphium 1 1 1
Theridion tinctum 1
Tibellus oblongus 1 1
Trematocephalus cristatus 1 NS
Uloborus walckenaerius 1 1 NR
Xerolycosa nemoralis 1 1 1 NS
Xysticus cristatus 1 1 1
Xysticus erraticus 1
Xysticus kochi 1
Xysticus lanio 1
Xysticus luctuosus 1 NR
Zilla diodia 1 1 1
Zygiella atrica 1 1

Total 39 55 49
Cons status 5 10 9
Percentage 12.8 18.2 18.4

Iping & Stedham are on 204 species of spider and a whopping 25.0% of these having conservation status, Rye Harbour is very close to this with 201 species at 19.9% conservation status. Then we have Graffham Common with a grand total of 141 species (the 80 mentioned above was from the six visit standardised survey in 2017 alone) and a total of 17.0% of these have cons status. Old Lodge is next with 139 species with 11.3% conservation status. All these sites, except Graffham Common, are SSSIs (or with higher designations) with years of recording behind them.

And that's just the spiders. Other taxa are showing some similar exciting changes but that will have to wait for another day.

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