High Plain Drifter

Posted by Graeme Lyons , Tuesday 27 August 2019 12:06

I've just got back from another trip to Ken Hill. Along with the structured surveys I am doing there, building a site list is also a key task. That means that casual records of species made when you are doing different jobs, or moving between plots, are extremely important. Such as this emerging Humming-bird Hawk-moth recorded on a large area of acid-grassland with some heath known as the Plain. Now these are not all that scarce as a migrant but I have never seen this before, an adult that had clearly still not taken its maiden flight. Last summer I saw an adult ovipositing on Lady's Bedstraw at Heyshott Down but this was a first for me. Annoyingly, my memory card broke so I only had my phone camera for much of this trip. However I took this shot and posted it on Twitter not thinking that much of it, three days later it reached 1000 likes and over 150 retweets. I think even the Calosoma sycophanta event only got about 300. Anyway, not bad for a phone shot!

I've now recorded over 700 invertebrates there this year and the list is rising all the time. Highlights included a new location on the site for Breckland and Fallen's Leatherbugs, the impressive wasp Podalonia affinis (also on the Plain), the Scarab Shieldbug, the unpronounceable Sphragisticus nebulosus (a new species for me). Also on the Plain (and cathartic as I caught one last month but it flew off before I could pot it) were my first stiltflies. They turned out to be the notable Micropeza lateralis. Also on the Plain, quite a few Hedychrum nobile. A not very impressive camera photo of a very impressive jewel wasp.

To the north of the site this very late Agapanthia villosoviridescens. It's usually a late May to June species.

We ran a moth trap on the Plain which would have been more successful if the generator hadn't kept cutting out. We did add a few species to the list such as this Vestal.

Always a pleasure to see Antler Moths (below) and True Lover's Knots too.

However it was the by-catch that proved most interesting. There were lots of aquatic bugs and beetles that were all new to the site, hundreds of Water Veneer moths too. Quite a few carabids came to light  but the best was Harpalus froelichii which I have only seen in the Brecks so far. Talking to Steve Gale I was expecting to see this at Ken Hill but as yet I had not knowingly picked it up. It's Nationally Rare, Near Threatened and S41 and adds to the Breck-like nature of the site's flora and fauna.

The vegetation structure and composition plots are now complete. I added a couple more arable plants to the list including another good one which was also a lifer and a 7 point scorer. This is my new favourite grass, Rye Brome which was confirmed by vice county recorder Richard Carter when we met up in the field. It's Vulnerable and nationally scarce. Along with Corn Mint (scores 1) that gets the site index for arable plants up to a whopping 113!!!

A couple of veteran trees were really impressive. This 6.5 m+ (that doesn't even include the 2.3 m branch on the right) girth Pedunculate Oak is one of the biggest I have ever seen.

And this Common Lime Tilia x europea was 4.31 m girth!

And a few fungi were about too, such as this Dyer's Mazegill on pine. I've started the NVC map now, so I will be doing some series footfall (this last trip was 42 miles) for the last two visits. Whatever will we find next month?! A huge thanks to the Padwick's, Richard Carter and everyone else at the Estate for their support and time and making it such a fun project.

Weevil genius

Posted by Graeme Lyons , Friday 9 August 2019 18:30

Last Saturday I completed visit 5 of 6 of the invertebrate survey of East Head and it was a great day, I had to reschedule at short notice due to poor weather and was expecting to be doing the survey alone but I was wrong. Mark Gurney, Lee Walther and his family were all able to join in at short notice

Working in conservation, I have been lucky enough to work with so many of the great naturalists of our time and Mark Gurney has got to be up there. The last time we spent the day entomologising was about 2012, you can read about it here. Here is Mark with his legendary weevil fork.

Seven years later and Mark has levelled up becoming a national specialist on weevils. His weevil guides are making this unnecessarily difficult group much more accessible, even the apionids. In the field, Mark now uses multiple forks and has a new outfit. Seriously though it's great to still be working together all these years later after our RSPB days, even though we are both in different roles now.

The highlight for me was the weevil Protapion dissimile. I mentioned there was a big patch of Hare's-tail Clover over there. We got to it, turned the suction sampler on for 30 seconds and there was a male, complete with funny tarsi and swollen first antennal segments. It's great when it all fits together like that. This was a new beetle for me and only the 7th Sussex record. 

We found some living specimens of Dicranocephalus agilis. This is the only known site for this bug in Sussex. So far I have only found a dead adult, so it was good to find these nymphs on the fixed dunes where more dead litter builds up beneath the plants.

The proportion of species with conservation status has dropped slightly but is still incredibly high at 16.2%. Here is one of Mark's photos, the Nb Anerastia lotella. A mainly coastal pyralid that feeds on grasses. I also found a dead Shore Wainscot which was cathartic as I thought I had the larva earlier in the year but couldn't confirm it. I also found another Hypocaccus dimidiatus in the mobile dunes.

And another one of Mark's, a plant tick for me. Lax-flowered Sea-lavender.

Who needs a moth trap when you have a pair of eyes?

Posted by Graeme Lyons , Thursday 1 August 2019 13:18

Or as I initially called this blog post: Passive sampling vs. active sampling.

I am a big fan of moth-trapping, don't get me wrong. It's a great way of racking up vast numbers of records for a site in a short space of time without leaving the comfort of your home but just how valuable are these records? The moth trap we run at Southerham picks up lots of moths off the chalk but it also gets lots of moths from the nearby Lewes Brooks wetland that are definitely not breeding on site. There was even a Pine Hawk-moth recently and there is very little pine nearby.

When I am doing surveys of invertebrates, I treat moths like any other taxa. You never catch a 100 species in a day, no way near that, but the moths that you get are almost always species that are breeding on a site. In the last month Glenn and I have been carrying out a vegetation survey of Malling Down and I have been constantly distracted by moths during these surveys. Although this site is extremely well recorded, we have added quite a few rare and scarce species.

First is Mecyna flavalis. This pRDB3 species is known really only from Deep Dean in Sussex, I went there with Michael Blencowe to look for it eight years ago and have not seen it since. It occasionally turns up in moth traps but this is the first record in the field of a specimen away from Deep Dean. Frustratingly I did only see one, which is a lot less significant than two, but the habitat was exactly the same. Extremely tightly grazed south facing chalk-grassland. This moth was not here by mistake and I would expect we will see this moth here again soon.

Yesterday we found the smart looking Moitrelia obductella (pRDB3). It would seem that this is the first record in Sussex that wasn't in a moth trap and it was also new to Malling Down.

Also yesterday were two Chalk Carpets (known from the site but I always get an eight-figure grid ref for these as they are on the real S41 list).

And the nationally scarce b Dingy White Plume which is common enough on the Downs where there is Marjoram, also new to the site.

Yet finding larvae in the field is even better. You're guaranteed it's breeding on site if you find larvae. Not rare but Glenn spotted this Small Elephant Hawk-moth in a plot last week, the first I have seen of this species. It really does look a bit like a Grass Snake! It lacks the spine at the back of Elephant Hawk-moth but also the eye spots are more detailed and a bit more like Peacock butterflies eye spots.

I would love to see more people finding larvae and adults in the field. And just so you know you don't need a trap to find rarities, here is a quick reminder of the Purple Marbled I found at Seaford Head a few weeks ago when I didn't even have my net to hand, just a tiny glass tube.

And out of county but last week I found a Vestal in a bog in the middle of nowhere.

And if you target a specific food plant for inverts that only eat that plant then you often turn up the goods. I beat a Crab Apple at asite in Surrey recently and this Argyresthia ivella came off it, the only time I have ever seen this Nb species. What was perhaps more unusual was the bare-footed man who appeared out of nowhere playing the theme tune to Lawrence of Arabia on a flute. I would like you to appear doing this whenever I get a lifer from now on please. It was magical.

And I got a lifer in my own house yesterday morning whilst brushing my teeth. I looked up next to my dried Hops to see a little pyralid I didn't recognise. I had the back door open the night before so it must have come in that way. Or so I thought. On closer inspection it was an Indian Meal Moth Plodia interpunctella (it was neither spicy or filling I should add. Om nom nom). An adventive species, I think I found it right next to its food plant. They must be eating my dried Hops! It's quite a smart little beast though.

So you don't need a moth trap to find rare and unusual moths, but they will probably be mainly micros!

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