2000 and beyond!

As many of you know, I have been keeping a pan-species list for a year and a half. A pan-species list (or PSL) is a list of all species that you have seen within either the UK or Britain and Ireland. My main target, that I set in the new year, was to get to 2000 species by year-end, which was always going to be a big challenge for me. I started the year on around 1300 species and retrospectively I am very pleased at the number of species I added during the course of the year.

Just a couple of weeks ago I was on the home straight. I needed just 29 species for me to reach the magical number however I was in the last, and generally toughest month due to the lack of many invertebrates. However, I had a field trip planned which would hopefully get me all the way.

On a cold Sunday morning I met several other bryologists (bryology is the study of bryophytes – mosses and liverworts)/naturalists in a car park in the Lewes district of Sussex. We were at Chailey Commons for a meeting of the South East group of the British Bryological Society.

Our first stop on our outing was the short acidic grassland immediately next to the car park. There were a few common grassland species here, including the very familiar Rhytidiadelphus squarrosusor Springy Turf-moss. This species is not only confined to acidic grassland like this but can also be found almost anywhere with short grass. For example it out-competes the grass in our lawn in some places! Once you have seen this species regularly it becomes quite distinctive, it is medium to large sized (for a moss!) with a red stem. It has very short, thin leaves on the stem as well as slightly larger pointed leaves on the short branches and at the apex.

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Springy Turf-moss (Rhytidiadelphus squarrosus)

Another species found in this short grassland was Kindbergia praelonga, or Common Feather-moss. This is another largish moss which, as its name suggests, resembles a feather. Unlike Rhytidiadelphus squarrosus is completely green, including the stem. It has opposite branches with leaves similar in size to those on the green stem. The branches become shorter, like the tip of a feather.

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What I believe to be a frond of Kindbergia praelonga

After examining the grassland, we moved to a small patch of woodland around a quite large but seasonal pond. This pond is one of the few sites outside of the New Forest for Fairy Shrimps, however I needed to have been visiting in summer for a chance to see one of these rare crustaceans.

In this small wood we found a number of common woodland species, including our first liverworts of the outing. The first liverwort I came across was the small but abundant Metzgeria furcata, also known as the Forked Veilwort. This liverwort is very thin and forms small patches on tree trunks with the thalli (the leaves) adpressed to the substrate. It is the most common thallose liverwort and away from the coast, the most frequently encountered Metzgeria species. It also occasionally grows on rocks, although more frequently in the west of Britain where it is generally damper.

Along with that species of Metzgeria we also came across another species of the same genus: Metzgeria fruticulosa, or Bluish Veilwort. This is much less common than M. furcata, and a new species for me. This species is separated from furcata by the gemmae, which is “a small cellular body or bud that can separate to form a new organism”. Metzgeria furcata only produces gemmae rarely in Britain however fruticulosa is almost always gemmiferous, with gemmae located at the tip of the thalli.

We also encountered several patches of the moss Fissidens taxifolius (Common Pocket-moss) on the soil on the steep bank leading down to the pond. The genus Fissidens is a tricky genus for beginners as specimens often need close examination, either in the field with a hand lens or with a microscope. Luckily I was with lots of people much more knowledgeable than myself, so the specimens we found were quickly identified as this species.

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A species of Fissidens from the Cotswolds last year

After recording everything that could be found in that small patch of woodland we headed to a habitat I have never explored before: a WW1 trench! There were a number of very interesting bryophyte species in this trench that was used for training in the Great War, including one of the least common bryophytes of the meeting: Aulacomnium androgynumThe common name of this species is Drumsticks, named after the very distinctive reproductive feature, which comprises of a long stalk with a ball of gemmae at the vertex.

A variety of different mosses and liverworts were not the only new species I found in the wartime trench. There were also a range of ferns growing on the muddy bank and luckily a member of the Sussex Botanical Recording Society, Helen Proctor, was on hand to help me identify a few. Most were common species that I had recorded before, however one was a common species that I hadn’t recorded before! This was the Broad Buckler-Fern, Dryopteris dilatata. Distinguishing this species confidently from other species is possible by looking at the brown, papery scales on the stem. If these scales have a dark centre, then they belong to the Broad Buckler-Fern.

After a thorough exploration of the trenches, we moved on to an area of damp heath. Here there were Sphagnums aplenty! Sphagnums are large mosses which love damp, boggy habitats on the edges of streams and other water bodies as well as in bogs and marshes. The genus is quite easy to identify from other mosses due to its size and elongated, upright shape with a thick capitulum, which is a compact head containing new branches. However, identifying Sphagnums to species level is much trickier! For a confident identification one will need good literature, such as the key in the British Bryological Society’s Mosses and Liverworts of Britain and Ireland: a field guide. Fortunately there was also a Sphagnum expert with us who was able to verify what we found. I was quite pleased at the number of Sphagnum species we recorded on the outing: compactum, fallax, capillifolium, papillosum, palustre and fimbriatum. However, this is only a small fraction of the species of Sphagnum in the UK!

While we were examining the Sphagnum one of the members of the field outing flushed a medium-sized, stocky bird from the leaf litter. It flew high in the direction of the road. I stared at it as it flew off with my mouth agape for a fraction of a second, before I exclaimed: Woodcock! These plump wading birds are related to the Snipes, however they are unusual in that they are nocturnal; they often feed away from water (on moist pastures for example) and they roost in woodlands. Woodcock was one of my bogey birds: species that I really should have seen but hadn’t. I have traipsed through many woods in my local area hoping to disturb one from its daytime rest, which is by far the easiest and most common way to spot a Woodcock, without any luck. Therefore I was exceedingly pleased to have finally come across one.

Soon after we flushed the Woodcock, it was time for me to head off. When I arrived back home I counted up the number of new species I had found and I was pleased that I had just made it to 2000, with Woodcock being species number 2000! Now it is time to think of a new target to keep me motivated to find more interesting wildlife. My next PSL target is to reach 3000 species by my 15th birthday in August 2018.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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The Emperor of Knepp

My Pan-species List is going along quite nicely and I think I will comfortably reach 2000 species by the end of the summer holidays, which is my target. However, I haven’t added another new butterfly species for a very long time. So on Tuesday, that is what I set out to do.

Knepp Estate near West Grinstead is one of the best places in Sussex to see the elusive Purple Emperor butterfly. Purple Emperors spend most of their time in the canopy of large Oak trees and there are many huge trees at Knepp, which also makes the estate good for saproxylic beetles. Saproxylic beetles are beetles that depend on dead or dying wood. Also, due to Knepp being part of a rewilding project, there is lots of dung about. Rewilding is where you take a location and try to restore it to the state that it was in many centuries ago. This involves using substitutes for wild boar (Tamworth pigs), aurochs (long-horn cattle) and other animals. Dung is good for Purple Emperor butterflies because they can harvest moisture and nutrition from it.

Apparently, to entice Purple Emperor butterflies down from the canopy, you need a banana and some fish paste. On Tuesday we chose fish paste, and we spread some on a slice of bread. After we had walked down a nice track to get to the Purple Emperor hotspot in the centre of the estate, we climbed up onto a tree platform and I unwrapped my fish paste bread. It wasn’t long before the flies began to arrive, but Purple Emperors were no where to be seen.

The weather conditions were far from ideal for the Purple Emperors. It was dull and very windy, there was no sun to warm them up and at the tops of the trees even these very large butterflies would have difficulty flying. However, we kept searching, walking along rides where we hoped the butterflies would show. We were just about to head home when the sun miraculously came out from behind the clouds. It immediately warmed up but we didn’t think it would last for long. We carried on walking down the ride when I nearly stepped on a long black thing. To my surprise it exploded from the ground just beneath my looming foot and flew towards the hedge on the side of the ride. I had nearly stood on a Purple Emperor! I hadn’t noticed it because its wings were closed making it look like a black twig from above. It wasn’t the best of views, but I had seen a Purple Emperor!

Sooner than I thought, it came back and landed on the track, where it probed the ground with its proboscis. It was picking up minerals from the dirt that it wouldn’t be able to get in the oak canopy. As it spends most of its time in the trees, it doesn’t feed on flowers which is very interesting. Instead, it most commonly feeds on the honeydew that is excreted by aphids and also sometimes on sap. Another interesting point about the Purple Emperor is that they are sexually dimorphic, which means that the males are different to the females. The males are much more beautiful and have a brilliant purple sheen when the wings are at a certain angle to the sun. However, the female is larger, dull brown and never has the purple sheen of the male.

While the butterfly on the ground was picking up minerals, I spotted a second butterfly flying around at head height. However, it was too wary to come down and retreated back to the canopy. The male on the ground was also flighty, but I did manage to get a few photos from a distance:

So, that is my 33rd butterfly species. Which butterfly will be next on my list?

A Quick Walk down Mill Lane

 

This morning I walked along Mill Lane which runs along the east side of Hedgecourt Lake. What struck me first was the height that the Water Dock had grown to compared to the last time I visited the lake. It was at least the height of me if not taller. This is not unusual though, some plants can grow to more than 2 metres. This plant can grow in very tough conditions, these ones grow on the concrete wall of the lake against the hard wind and the severe waves that sometimes form. Equally large were the leaf mines that covered almost half of each leaf. Some leaf-mined leaves were about 75 centimetres long, so the leaf mines were huge! Whose larvae are growing up inside those leaf mines?

To identify the culprit, I visited a site I use regularly: http://www.ukflymines.co.uk
I went to the Rumex (Dock) section of the site and I saw that luckily there are not that many leaf mines on Dock in Britain. From the photos on that page I think that my species is Pegomya solennis. Pegomya solennis is a species of fly, unfortunately not new for my list although very impressive. This species is not a large fly, but the key to its very big mines lies in teamwork. In each mine there are two or more larvae that at first work together making a wide corridor. They then separate and each form a large blotch which all fuse together making one large blotch from which they feed. Sometimes the blotch size is increased even further when the blotch joins the blotch from a different leaf mine.

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The larvae feed on the leaf from inside these blotches.

Along the grassy verge between the lane and the lake there are several large patches of Bird’s-foot Trefoil, Ribwort Plantain and Black Medick. I thought these large patches might hold some specialist species but alas not much was swept from them using my net. The only species of interest was a single Platycheirus peltatus, a species of hoverfly and my 94th fly species on my Pan-species List.

Moving on, it was still windy and not too warm so most of the wildlife was hiding away. I stepped down onto one of the fishing jetties to get a closer view of the lake wall without the risk of falling in to the nippy water. On top of the concrete wall was a hole, which was occupied…

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The white spherical object in the centre of the hole is an egg sac, which belongs to a very large spider. I tried to coax it out from the hole, but it wouldn’t come. I’m not certain what it is, but one possibility is the mouse spider, Scotophaeus blackwalli. However it is usually found in sheltered places indoors so I’m not sure what it is doing on this exposed wall if I am correct.

On some more Water Dock further along I noticed a colony of aphids. It is often not hard to identify aphids when you see a colony on a particular species of plant. For this one I just searched with Google ‘aphids on dock’ and I was presented with two options: Aphis rumicis and Aphis fabae. Aphis rumicis is more plant-specific, being found on mainly dock and sometimes on rhubarb. Aphis fabae (the Black Bean Aphid), is much less so being found on a wide range of vegetables. Unfortunately the two are quite similar, although I am leaning towards A. fabae due to the paler legs shown in many of the photos I have seen on this species. My 50th hemipteroid (bug) for my Pan-species List! In my (not great) photo, the colony appears to be being attended by a Lasius ant.

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Suddenly the sun emerged from behind the clouds and everything seemed to suddenly wake up. There were loads of umbellifers on the lake shore which were great for invertebrates although I had little time to examine them closely. What I did find, however, is a mini-miner. These are very tiny bees in the genus Andrena, which I don’t come across too often. Their larger relatives in the same genus I more often come across. There are 10 mini-miner species compared to 57 other Andrena species, although I find them much harder to identify. Also, many of them have very restricted distributions.

I potted this tiny bee and when I arrived back home I took a few hasty shots though the gap between the lid and the pot. The long, very white hair caught my eye and helped me when I attempted to identify it using Steven Falk’s Field Guide to the Bees of Great Britain and Ireland. Currently I think the most likely species is Andrena niveata, the Long-fringed Mini-miner. Modern records are restricted to South-east England and it is not very common, therefore I am tentative with my identification and I will hopefully get it checked under the microscope or with an expert. In the book it says: ‘the body hairs are much whiter than in other mini-miners…the overall effect is thus of a very silvery, strongly marked mini-miner’. This definitely fits my bee.

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I was very pleased with the number of interesting and new species that I found this morning, given the short amount of time and the unfavourable weather conditions. I can’t wait until the summer holidays when there will be more time to explore!