This post is like so meta. Cubed. I went to an undisclosed site in East Sussex a few weeks ago and was shown a small natural cave in a sandrock outcrop. I was in there like a shot! There was the ubiquitous
Metellina merianae (or as I call it the Cave-entrance Spider) which I see in any tunnel or cave. There were also dozens of
Meta menardi, the true cave spider. This is only the second time I have seen this large and impressive spider in Sussex. Well, that's probably because you don't spend enough time in caves I here you say. Wrong I say. I suddenly thought about it and I have looked at loads of caves and tunnels in Sussex with bat specialists such as Tony Hutson and moth-ers like Steve Teale. In fact, I've looked at plenty of (what I assume are) suitable sites and I just don't see this spider.
So why is it so restricted? I have no idea, so I will pull out the records and have a look at the metadata. First off this record is in a natural cave. It was very wet with flowing water, there were perhaps 40 in there that I could see. Lots of mosquitoes and a Herald moth. Mammal droppings too, so plenty to eat. Secondly is the previous record in Sussex which was found in the workshop at Woods Mill by Michael Blencowe, I confirmed it as Meta menardi. It was the first record for West Sussex. The far end of the workshop is a bit musty but mostly quite dry. It's pitch black until you open the door or turn the lights on. No real opening and very little food. We only ever saw one there and I've not noticed it since.
Prior to that there are three East Sussex records (all bar one are of single female records). Two from the soft-rock sandy cliffs to the east of Hastings in 2006 (this record is of three females) and 2003 have no metadata so I can't comment on these, so lets assume they are natural caves. The only other record was made, would you believe it, from Beachy Head! This record states that it was "found in a fissure on cliff top".
So most of the records are from relatively small natural caves with permanent openings. This also tallies with where I have seen them up north. The Woods Mill record is the anomaly. So, maybe it's worth looking at smaller more natural caves than the bat tunnels I have spent more time in (where you are more likely to see a Bloxworth Snout moth than a cave spider!). There is also the scarce
Meta bourneti to look out for, that hasn't been recorded in Sussex yet.
On the 9th January I met up with Sharon Pilkington and Tom Ottley to look at some of the rare bryophytes growing on the sandrocks at Eridge Rocks. It was an interesting day, I managed to see seven species I hadn't seen before (4156) including some quite scarce ones for this region. It was good to talk about the management of these often over-looked plants and to see that we are mostly getting it right too. Tom thought that the rocks were probably looking the best they had done in the last 50 years for this rare assemblage of tiny plants. A few tweaks that we could make include clearing brambles from some of the boulders and removing some of the lower branches from evergreen shrubs to let the dappled sunlight that these plants demand (direct sunlight or complete shade are a sure way to eradicate most of the species).
Here are a few of the species we saw. This first was perhaps the rarest of the mosses,
Dicranum scottianum (we only saw three tiny plants) but I was particularly pleased with this shot. It is taken with the lens looking directly up the side of the sandrocks. It was an incredibly dull, overcast day which I think the Coolpix 4500 does well in.
This TINY liverwort is known
Scapania umbrosa and was yet another species the bryologists were quite excited by. Nearby, this boulder, with a birch growing from it, was also a hot spot for a few scarce bryophytes.
Including this endearing little acrocarp (did I just say that). Tiny luminous-green sea urchins spring to mind. It's yet another species that can thrive on the sandrock,
Campylopus fragilis.
A phrase that kept popping up in the species accounts in the literature for these scarce species was 'hyper oceanic', essentially meaning of a far north-westerly distribution close to the Atlantic. In the Weald, we have many of these species, particularly on the sandrocks, but they are often very rare in the region (where they might be common in the north-west). It must be a specific set of climatic and substrate conditions that are provided here but it is something well worth holding on to. Without the appropriate management at Eridge we would certainly lose these plants to succession as Holly, Yew and Rhododendron cast their dense winter shade over the rocks. This is a great example of monitoring and management working hand in hand with the specialists feeding their knowledge and advice straight to us at the Trust in the field. If we want to hold on to rare and scarce species that have such specific requirements, we cannot rely on a 'one-size fits all' approach to their management and natural processes here would be damaging. Species-assemblage focused management is therefore vital if we are to maintain the more unusual plants and animals at Eridge. Small scale management like this is often referred to as 'gardening' by some conservationists these days. Call it what you like, I see it as
exactly what is required to maintain a rare and precious assemblage and that's exactly why I have conservation written through me like a stick of rock!
Wow what a day, I just tallied up all the firsts and I added 13 species to my list today (with a LOT of help from Howard Matcham). We went to Wakehurst Place to look at the vegetation that grows on sandrock cliffs. There are some pretty rare liverworts (I saw five new ones day) that show a relict distribution in the Weald where their main stronghold is the north west. This includes this rather fancy (it's glaucous!) liverwort, Calypogeia integristipula. Here it is again with gemmae.
This is also a real rarity, we saw what is most likely to be the vast majority of this liverwort that exists in south east England, Harpanthus scutatus.
Perhaps the most abundant moss on the rocks after the common Mnium hornum is Tetraphis pellucida.
Here is Howard investigating a tiny patch of green on a huge rock. It's amazing how someone elses expertise appears so effortless to them, I'm lucky to be able to spend time in the field at a leisurely pace (I wasn't working today) with such a great botanist!
Not far from there we noticed this HUGE patch of Tunbridge Filmy-fern riding out the hot weather unscathed.
If you think I wasn't keeping an eye on the invertebrates today, you'd be wrong! I caught up with this smart little harvestman Megabunus diadema. Check out his eye-spikes, like a cowboy's stirrups. However, the thing that got me really excited was an amazing black and red bug called Corizus hyoscyami but I didn't get a photo!
So, all in all I have added 5 liverworts, 2 fungi, an algae, a moss, a moth, a bug, a fly and a harvestman leaving me on 3264! Watch out Martin Harvey I am closing in on you!
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