World of Leatherbugs

Posted by Graeme Lyons , Wednesday, 22 May 2019 07:37

I've just got back from my monthly visit to the Ken Hill Estate where I am carrying out a series of baseline surveys before they restore some 400 ha to a more natural state. Wow, what a place. On Sunday I recorded the most invertebrates in a day's work I have ever recorded. Currently at least 275 species and with all the specimens collected it will be over 300. It was the bugs that stole the show though. Above is the nationally rare and Critically Endangered Breckland Leatherbug Arenocoris waltlii. I found two of these during the timed counts on a sandy arable field covered in Common Stork's-bill. You can see the 2nd segment of the antennae expands towards the tip and it lacks the white 'v' on the pronotum of the closely related Arenocoris fallenii. Tristan Bantock was telling me that this species is expanding its range but this record is likely to be the most northern record in the country.

After the count was finished I really felt like I needed to cover this area in some more detail so went back for an hour and it really paid off!

Here is the nationally scarce Slender-horned Leatherbug Ceraleptus lividus.

And the very hairy and fairly common Denticulate Leatherbug Coriomeris denticulatus.

I found a Rhombic Leatherbug Syromastus rhombeus too! As I was photographing this, I saw in the view finder that it ran in front of another bug. Which turned out to be the species closely related to the Breckland Leatherbug mentioned above... is the nationally scarce Fallen's Leatherbug Arenocoris fallenii. Both a pale/contrastingly marked one and a browner one closer to the Breckland Leatherbug above. In both individuals though you can see the second segment to the antennae is parallel sided towards the tip and there is a white 'v' of tubercles on the pronotum.

But it didn't stop there! This is what I assume is an early instar Alydus calcaratus nymph (also nationally scarce). An amazing ant mimic.

Other nationally scarce species associated with Common Stork's-bill were Megalonotus praetextus.

And Hypera dauci. It really is just like the Brecks. There was a Woodlark singing nearby too (that refused to show itself during the bird survey). Oh and another Heath Shieldbug Legnotus picipes was there which I picked up last month on a different part of the site!

And to show how sandy it is, the nationally scarce Zelotes electus was also present. This spider is usually found on sand dunes and also the Brecks (see the BAS page above). Oh and I also hit 250 spiders for the year!

Here is that amazing bank and associated fields. With extensive grazing, it's highly likely that this already rich habitat will greatly expand. The continued presence and expansion of these kind of swards in the south could therefore act as a measure of success of the restoration.

Elsewhere in the woods there was also some excitement, with Dendroxena quadrimaculata (nationally scarce b) just sitting on a bramble leaf. This silphid is unusual in that it specialises in hunting caterpillars. It's only about the fith record I have made of this species.

And the striking deadwood cranefly Ctenophora pectinicornis. This nationally scarce species was beaten from recently fallen deadwood.

And how is it that I have seen a third of the UK's beetles but not this before?! Despite seemingly spending half my life beating oak. It's clearly not common in Sussex. The Oak Leaf-roller.

Just looking through the list, it might be the most shieldbugs, squashbugs, leatherbugs and allies that I have ever recorded in one day. Here is the full list in no particular order, 19 in all.

Bishop's-mitre Shieldbug
Slender-horned Leatherbug (NS)
Heath Shieldbug (NS)
Dock Bug
Juniper Shieldbug
Birch Shieldbug
Sloe Bug
Cinnamon Bug
Breckland Leatherbug (NR)
Fallen's Leatherbug (NS)
Rhombic Leatherbug
Denticulate Leatherbug
Small Grass Shieldbug
Green Shieldbug
Rhopalus subrufus
Stictopleurus abutilon
Alydus calcaratus (NS)
Parent Bug
Gorse Shieldbug

Now for some plants. I found a few Wild Service Tree saplings in the woods.

The Vulnerable Prickly Poppy on the sandy field to the south.

And the Near Threatened Hoary Cinquefoil on the Plain.

The bird survey was wrapped up and the highlights included Turtle Doves, Cuckoos, Whimbrel, Woodlark and much more. Wow, if May was this good, I cannot wait until the June visit! The vegetation surveys will start then too rather than just casual observations of plants.

I love Uloborus

Posted by Graeme Lyons , Tuesday, 14 May 2019 13:45

A couple of years ago we found a new population of the rare heathland specialist spider Uloborus walckenaerius at Graffham Common. On Sunday evening I popped over to add it to my year list and do a bit of recording. I swept this big one in the first sweep net and then didn't see another. It really wouldn't keep still so the photos are not great. Here is a celebration of this unusual spider. I love the tufts on the abdomen.

Also there was an immature Philodromus margaritatus, also known from the site.

A female Araneus sturmi.

Also I finally got Evarcha falcata for the year. These making my spider year list up to 242 species. I swept three Ampedus elongantulus, really don't think this is all that scarce down here now. Also my first Spotted Flycatcher of the year. 

The Warbler Factory

Posted by Graeme Lyons , Thursday, 25 April 2019 08:07

Butcherlands. The most exciting, unpredictable and consantly changing Common Bird Census I have ever done. This is the eighth year I have carried out the four visit CBC there and it's amazing how much it's changed. Eighteen years ago this was all arable on Wealden Clay and was fenced and left to be restored to something more natural with pulse grazing by cattle currently pretty much the only management. No planting occurred and there are at least 30,000 oaks out there alone. Before looking at some of the detail though I am gonna cut right to the chase and tell you about what happened yesterday morning. First though a recap from my first visit on the 3rd April 2019. I had a Hawfinch fly over (my first since the previous winter's influx) and then surprisingly a male Dartford Warbler called repeatedly from a bramble bush. Not all that unusual to pick them up in bramble scrub away from the heaths outside of the breeding season (I've seen them in Sheepcote Valley on the edge of Brighton for example). 

Yesterday morning, the warblers were in full song. Whitethroats were EVERYWHERE. I recorded 44 singing males across the site. So when I got to the exact same area and heard Dartford Warbler calling again, I was pretty shocked. "It's holding territory!". I bungled the video last time so I got a quick video of it calling and you can see it fly from the bush to the left.

I thought I really should try and hear it singing, so I headed a few bushes away and crouched down out of view. It didn't work and the bird came towards me, scolding me from just a few metres away. I grabbed another video as it did so and it started singing a tiny bit. However what happened next was incredible. A female popped up out of the same bush! "THEY'RE HOLDING TERRITORY!". Some context here, there isn't any heather at Butcherlands, there is however hectares of low bramble scrub. This part of the site is on the edge of a sea of undulating bramble. It's also south west facing with a slightly sandy soil (more Common Bent/Cat's-ear than Heather). So it's hot, dry and with a structural component close to heather/low gorse. I never thought that this would be a thing at Butcherlands but these birds are much less fussy abroad. It may well be that this structural type and temperature envelope is rarely provided outside of the heaths in the UK.

Has anyone else encountered this in the UK before?

Yesterday morning my brain was totally fried from all the warblers. After this encounter I was doubting every Whitethroat that called, after all, if one pair of Darties could nest there, why not more? I really doubt I would have picked them up with so many Whitethroats there if I hadn't found the male three weeks ago. So many questions. So exciting!

I actually recorded over 75 singing warblers yesterday! My rule for difficult species pairs is this: if you're not sure, it's the commoner one. Think I'll call that 'Lyons' Razor'. It certainly came in handy with a few Blackcaps today. A Blackcap AND a Garden Warbler taking turns to sing from the same willow nearly made me lose my mind though.

Whitethroat - 44
Chiffchaff - 11
Garden Warbler - 8
Blackckap - 8
Lesser Whitethroat - 4
Dartford Warbler - 1

That's 76 warblers in all. Plus ten Nightingales and a Cuckoo. 

How has this changed over the last eight years though? With provisional data from yesterday's visit (this will change) the warblers look like this. A highly significant increase from linear regression. Only Chiffchaff and Blackcap came out as stable (as they are probably at capacity in the hedgerows and fields edges - for now).

And then like this if you break them down to species.

It's not all winners though. Nightingales have dipped a bit (although this trend is not significant) and Skylarks have nearly disappeared completely (a significant decline), they are still holding on this year though.

But look at the overall number of territories for all species (no suggested data here for 2019) shows a significant increase.
If you break the data down to Red & Amber listed Birds of Conservation Concern and compared to the Green listed, there is no significant trend with the scarcer birds but a highly significant one with the green birds. Showing that the generalists are doing better/quicker than the specialists. You would expect this though. This graph would look very different if Whitethroat was still amber listed but that is not something to wish for!

Species-richness of birds holding territory looks like this from 2012 to 2018 and shows no trend being about as level as it could be.

Linnet and Dunnock are two of the other species that have colonised the centre of the fields and have rocketed up significantly over the period. However the star of the show is yet to arrive. Last year FOUR Turtle Dove territories were noted and this chart shows how they have fared over the period. Wow, wasn't expecting to analyse the whole data set. Got a bit carried away there with linear regression.

I think the success of a project like this is when the site can sustain all of the species that the site has the potential to carry. So losing the red-listed Skylarks to the red-listed Linnets completely doesn't seem right to me just because we don't have an easy way of controlling the scrub. It's always early successional habitats that lose out without a constant effort to keep them open, that's why the associated species are rare. But I am also a fan of not trying to have everything everywhere all of the time. Additionally, scale is a factor here and it may not be possible to have all the successional states in 80 ha in a functional way. It shouldn't stop us trying though. How far back do you go though? After all, soon after the project started some 18 years ago (way before monitoring began) there were breeding Lapwing out there. The site would have to look very different to support them again, not something I would propose at all. You can go round and round with this. One thing is certain though, succession goes in one direction and never stops.

Over the last eight years I have recorded 73 species in the survey but this morning added another one to the list in the form of a pair of Egyptian Geese flying over. Whatever next?!

Endangered spider best birthday gift ever!

Posted by Graeme Lyons , Tuesday, 23 April 2019 19:33

So last Tuesday I went hunting spiders at Levin Down and Iping Common on my birthday. I did pretty well but didn't really find anything I hadn't seen before. Until a few days later when I found a little thing in the bottom of my utility belt (it's not a bum bag) which I assumed was an immature in the field but clearly looked different enough for me to put it in its own tube. It took a while to figure out it was an adult female Scotina. Now I have seen Scotina gracilipes and celans only very occasionally and find them quite generic looking but this was found by sieving moss in chalk-grassland, so there was a chance it was the Nationally Rare and Endangered Scotina palliardii. I wasn't sure, so sent it off to Peter Harvey who confirmed it was today. There is one record for Shoreham with a vague date, which is the only other Sussex record. It's the 392nd spider recorded on a Sussex Wildlife Trust reserve and seems to be a genuinely scarce beast. It's the first larger spider I have added to the reserve list since year listing spiders became a thing this year (the only other species so far was Sintula corniger). Can we get to 400 spiders for the reserve network? Levin has some really good spiders, with 18.8% of the 64 spiders recorded there having conservation status.

A few nights later, I went over to see my mate Simon who has recently moved to Shoreham. Last year I did an invertebrate survey there for the Friends of Shoreham Beach that involved extensive suction sampling on vegetated shingle. I had another go for 10 minutes and found a spider genus (in good numbers - six at least) that I had never seen before. Zodarion. I also didn't have any genitalia diagrams of this genus so wasn't able to identify them, so I sent them to Peter along with the Scotina and he confirmed them as the most likely candidate, the Nationally Scarce Zodarion italicum which is a new species for West Sussex. They looked like very fast money spiders in the tray, also not far off a reddish Phrurolithus festivus in the way they moved (which I found them with). What's really strange is that I found so many of them so easily but didn't pick them up last time. The one big difference was it was at 7.30 pm at the end of a very warm day, so maybe they are more active at this time of day.

I end the day on 194 spiders for the year! Can I find another six spiders in seven days?

Bugs, borders and bugs with borders

Posted by Graeme Lyons , Saturday, 20 April 2019 13:54

Bob Foreman and the SxBRC have updated the excellent Sussex Shield Bug Atlas with all our records. I have done a wee bit of analysis to show how much things have changed in the last year. It surprised me just how much better recorded shield bugs (and allies) are now we have the atlas. It's already out of date though, as yesterday I recorded Bordered Shieldbug Legnotus limbosus new to my home 1 km square as I was walking to the shops. Here is a rubbish phone shot.

Oh and here (and the top photo) are shots I took of one I collected in the suction sampler from Levin Down this week, first record there since 1997. You can see the detail on the clypeus here that separates it from the scarcer Lengotus picipes.

Anyways, back to the analysis.

Here is the overview before

And after the update

First off, the total number of species per 10 km square rose by over 10% from 15.7 to 17.3, That's pretty cool. Around 63% of 10 km squares showed increased species-richness of shield bugs.

The total number of records per 10 km square rose by nearly 22% from 80.8 to 98.3. That's really impressive. Around 90% of 10 km squares showed some level of shield bug recording in the last year. The biggest jump was in the most recorded square which went from from 676 to 777 records over the last year.

The most species-rich 10 km squares now contain 31 species, these being around Hastings and immediately north of Hastings. I wonder if this is mainly due to Derek Binns? Can we beat 31 species I wonder? The biggest jump is the square in the far north west of West Sussex where the partial square bordering Hampshire went from two species to 13 species in the last year. Who is recording in this part of the world I wonder?

Have a look at the rise of the Western Conifer Seedbug. It's now been recorded in nearly as many squares as Green Shieldbug and Dock Bug and has already been recorded in two more squares than Hairy Shieldbug?! Partly this is down to its striking appearance, people love to record it on iRecord!

I leave you with one of my favourites, the Rhombic Leatherbug which I have added new to the square containing East Head already this year. Happy shieldbug recording! By the way I am thinking of year listing Heteroptera next year as I have had so much fun doing the spiders if anyone is up for it.

I've seen more than a quarter of the UK's spiders already this year!

Posted by Graeme Lyons , Wednesday, 17 April 2019 07:11

As it was my birthday I decided to have the day off. What this ended up being was me going to Levin Down and Iping Common to look for spiders. One thing I have learned though is if it FEELS like a day off, then that's OK. I had a few targets in mind and Xysticus bifasciatus was soon on the list. I love this photo as you can identify it from the palps. This area is always really good for this massive crab spider. Ozyptila nigrita evaded me though.

I have a confession to make. I really hate the genus Theridion. Well, I mean all the new names they have been split up to too. Not big enough to be real spiders, they have boring palps and also, no novelty heads like money spiders either. They are also only adult for about 30 seconds each year. Theridion mystaceum or whatever it is called now...

The real rarity was Phaeocedus braccatus though. I found these spiders at Levin in an area of moss a few years back and the young females were abundant yesterday. You can only just make out the six spots but they are there.

A novelty headed spider in the form of Hybocoptus decollatus which is abundant on the Juniper there. The highlight for me though was finding a beetle new to the reserve network, the tiny weevil Tychius squamulatus in the suction sampler. Violet Weevil was also new to the site.

Then I dashed off to Iping. It was cooler there sadly so my target species of a certain chevron-headed jumping spider was not to be found. I did add Hypomma cornutum, Evracha arcuata and Xerolycosa nemoralis though. It was however a male Araniella displicata that stole the show. What a beauty!

Another one I recorded months ago this year but a real beauty was Philodromus histrio. Here a pair were swept from the place I usually see them.

I recorded a total of eight new species for the year, making my spider list 172 species or 25.2% of the list. Collectively, the UK Spiders Facebook page has now recorded over a third of all the spiders too. Is it possible that I can get to 200 species in the first four months of the year?! Right, now I am off to set up a new survey in Surrey...

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