Holly Leaf Miner - Phytomyza ilicis

This week I have been collecting some data for the Agromyzidae recording scheme, run by a member of the Yorkshire Naturalists Union that I am becoming more involved with. As it is close to Christmas, the group put out a request for records of the holly leaf mining fly, Phytomyza ilicis.   This is one of few insects that can use tough holly leaves as a food source.

Females lays their eggs in the holly leaf in early Spring when leaves tend to be younger and softer. Larvae emerge from the eggs and tunnel along the leaf veins, creating a "mine". After a period of feeding, the larva turns into a pupa, then later an adult fly emerges from the pupa and leaf mine via a small hole, less than a millimetre in diameter, on the leaf surface.

The larva may not make it to the adulthood as it may be parasitised by the eggs of a wasp – which devour it - or it may be eaten by by a blue tit. If this happens, there may be evidence that the leaf mine has been pecked at/ripped open and the insect removed.

The holly leaf miner is common throughout Europe but appears under-recorded, so hopefully my efforts will help contribute some useful data.

I went for several walks around my neighbourhood and found signs of the leaf miner on many of the trees/bushes. They did seem more prevalent on the older, more mature holly trees. Young bushes or those that had been trimmed (eg. within hedgerows) seemed to be less affected by Phytomyza ilicis.

Sightings can be reported using iRecord (please submit a photograph and your location). 

The Great Glen

This week we are doing a bit of a road trip around the Great Glen. We have a number of sites to mop up that are spread quite widely, so are spending a night in each of three different hostels.

Our first night was in Fort Augustus. After a long drive from Blair Atholl, we picked up two sites on the road to Skye, stopping to check out the impressive commando memorial en route.

The surveys went well - we had two full sites to complete and saw plantiful butterflies. The habitat was relatively flat and scrub free so the host plant surveys were also fairly painless and quick to carry out. It was a hot day and the scenery was stunning, but I was quite pleased to be off the hill and out of the sun.

In the evening, we treated ourselves to an hours cruise down Loch Ness. We didn't see Nessie, or any other wildlife for that matter, but it was a pleasant way to spend the evening. 

Then it was back to the hostel, which had good facilities but seemed to be party capital of the world ...! 

Glen Affric

Our second day on our tour of the Great Glen took us to sites in Glen Affric. This is a small valley to the west of Drumnadrochit. The team that previously visited reported it as the "site from hell" and a "midge infested nightmare". To be fair they did survey in poor conditions. We returned on one of the hottest days of the year. My butterfly transect was a few miles on from Dog Falls. I didn't see our target butterfly, the Scotch Argus, along the road or in the bracken infested woodland, but near the end of the survey I found a nice patch of Molinia grassland by the loch side, with a pair of butterflies dancing along the beach. Success! It was beautiful down by the water with views over the loch and surrounding hills. I did have to do a solo plant transect though, up through said bracken infested woodland which wasn't so much fun.  Still, I felt lucky to have seen the site at its best, and it was a day that was good for the soul. 

Wester Ross

After our grand tour of Skye, we had a few sites to pick up in the north west of Scotland. We spent a night at the bunkhouse in Kinlochewe and used that as a base for our next two sites.

The first of these was a lovely site to the north east of Gairloch.  The area looked a great place to walk, and our site was part way along a path that linked the A832 (at NG8577) and Loch Maree, finishing at Slattadale - definitely a walk to add to my to do list.

Although the site was very beautiful, it wasn't kind to us!  The first time we visited we got caught in the rain. It was over one kilometer walk to our site, and just as we arrived it started to rain. We managed to complete one plant survey before returning to the car in torrential rain with midges swarming. I somehow even managed to get rain in the dry bag of my rucksack - pretty much everything I owned was wet. Luckily the car keys stayed dry, and everything dried out overnight in the drying room at the bunkhouse.

We returned the next day to complete the site. I had one plant survey to do by myself, and failed to navigate the best way to the start point of the survey, meaning that I climbed up a hill completely needlessly only to find I actually should be at the base of a steep rocky cliff!  I got there eventually, and my transect then took me down the valley crossing a stream several times. I was glad to get back to the car and leave the site behind!

We chased the weather all the way to our next site but unfortunately wasn't able to complete as the next weather front was coming in rapidly. There was time for a quick lunch stop at Rogie Falls though, and I saw my first salmon leaping upstream. 

Isle of Skye

This week I was lucky enough to be chosen to survey some sites on Skye. With it now being summer holidays it seemed everywhere on the island was fully booked so we spent our first night camping at Sligachan in the heart of the Cuillins, and actually had a transect to do right next to the campsite.

The weather was not kind to us - putting up a strange tent in the rain was not fun. We spent the evening in the bar sheltering from the worst of the weather. It didn't seem to rain much during the night and I stayed remarkable warm and dry, though the campsite was a sodden mud bath. We got up early and struck camp before the rain started again in earnest.  We managed to get two sets of host plant surveys done in between the rain showers, though did mis-time one and watched as the rain came in a band towards us from the Atlantic and gave us a thorough drenching as we tried to do the quickest survey ever!

Luckily we managed to get a cancellation in a bunkhouse, though it was nearly an hours drive away on the mainland. It was nice to be able to try out and not worry about the tent leaking though - and a lot easier to cook dinner with proper facilities rather than a wobbly camping stove in the rain. 

Our final day on Skye was much kinder to us. After driving back onto the island we managed to finish off the outstanding host plant surveys and do a butterfly transect in good weather. We stopped at a great little place for lunch (the Blue Shed Cafe in the Elgol peninsula) and had a delicious bowl of butternut squash soup. 

The weather allowed us to appreciate some of the magnificent scenery a bit more, though there were still clouds in the top of the Cuillins. The colours were amazing too - purple heather, green hills, brown seaweed, blue sky and aquamarine sea - very beautiful. It is a shame that the weather only perked up as we were leaving the island!

Then it was back to the mainland for our final site of the day, a National Trust for Scotland reserve near Kyle of Lochalsh (Loch Sgalpaidh). The landscape was beautiful with scenic views over the loch, though it was hard going underfoot with slopes of Molinia tussocks. 

The day finished with the classic tourist attraction of Eilean Dolan castle - probably the most photographed castle in Scotland so we had to do it too.

Plant Transects

Today we had a day of doing host plant V surveys, which involves following a 200m long inverted 'V' shaped transect within a 100m grid square.  This is most easily done by a pair of people (but can be done alone).  Starting in the bottom left hand (south west) corner of the square, the first person rolls out a tape measure on a bearing of 30 degrees.  The second person then measures the height of the vegetation every five metres, and also records any butterfly host plants that are present along the transect. 

After the first 100m, the top (northern) edge of the square should have been reached and should be around half way across the square.  The bearing is then changed to 150 degrees to aim for the bottom right hand (south east corner) of the square.

The host plants we were looking for today were for the Large Heath butterfly, and so were Common and Hare's Tail Cottongrass. 

One of the sites we visited was a heathland site a few miles to the north of Doune near Stirling. Our transects were along the edge of Loch Mahaick.  Much of the area was covered in dense coniferous forest, though there were some more open areas closer to the loch.  The area was still semi-wooded though, with evidence of replanting of native deciduous trees.  There was lots of rotting wood under-foot which, along with the Molinia tussocks and boggy pools, made it hard to walk the transect. This was made harder still trying to see through a midge net, as the little bugs were in abundance.

The Large Heath butterfly was not found here on a previous butterfly survey, but we needed to do the vegetation survey to assess whether this might be due to habitat change/suitability. Despite the re-wooding, there was still a large amount of hare's tail cotton grass on the site, with lesser amounts of common cotton grass. We kept our eyes peeled and didn't see the butterfly on this occasion either, though I did get a close encounter with a Common Hawker dragonfly.

Unusual Sightings

Spending so much time wandering around the countryside, I come across things I have never seen before and it is interesting trying to find out what they are. For this I turn to the miracle of the internet - Facebook, Twitter, iSpot, etc - and usually get an answer fairly quickly.

Two of this weeks finds include:

• A group of black objects found on thistle leaves - possibly insect larvae.  They were quite small - maybe 5-6mm long - and seemed to have barbs around the edges.

• A hard, orange object on stinging nettle, making the stem bend back on itself. This was about the size of a caterpillar, but did not seem to be alive and must have been in place for some weeks for the plant to grow like that.  It is possibly a gall or an extreme case of Nettle Rust (a fungus).

Hopefully someone will be able to help me out soon.

Ullapool

I visited Ullapool some years ago and enjoyed this area in the far north west of Scotland. It was great to be able to visit again. We spent a week in a small cottage a few miles outside of town on Ardmair Bay.

Most of our surveys were 1+ hour drive to the north, on the Assynt peninsula, where we were looking for the Large Heath butterfly.

In sunshine, the area is amazing and the views over the coast are superb. However, in the rain the area is decidedly more bleak!

We spent several long days trudging in wellies through the heathland, counting cotton grasses and looking for the butterflies. Most of our surveys were successful, and we got to visit some amazing places including surveying in view of the mighty Suilven.

In Scotland, the colours of the Large Heath butterfly are a bit more subdued and the eyespots on the underside are indistinct if not absent.

http://www.ukbutterflies.co.uk/species.php?species=tullia

We also saw some other amazing wildlife including common lizards and the wonderful great sundew (Drosera anglica), a carniverous plant that was abundant in some of the heathlands. One site had hundreds of colourful Magpie moths, but sadly that's not the species we were looking for!

Muir of Dinnet

Last week we spent a day in the Loch Kinord area.

Our first transect was to the north of the loch, in the Old Kinord area. Parking on a small lane, we searched for the Northern Brown Argus in the fields and woodland clearings round and about. We followed a old grassy track through the site, where there were various old hut circles and derelict farm buildings to explore. There were lots of butterflies flying, but not the ones we were looking for.

In the afternoon, it was a short drive around to the Muir of Dinnet / Burn o' Vat visitors centre where we parked up and had a late lunch. This was a popular place, with lots of families making us of the various marked walking trails around the loch and through the surrounding woodland up to Burn o' Vat, a huge pothole in the hillside. 

Our next survey transect took us through the birch scrub and woodland to the west of the loch.

http://www.walkhighlands.co.uk/cairngorms/loch-kinord.shtml

We were rewarded with a sighting of our target species laying eggs of its host plant, Rock Rose. The small white circular eggs can be seen on the leaf surface in the photo.

Loch an Eilein

Another great little walk is around Loch an Eilein just outside of Aviemore. There is a small charge for parking, but there is a visitor's centre selling gifts and refreshments as well as toilets, so I don't begrudge a few pounds for the facilities.  There is a lovely walk around the loch which is around 7km long.

http://www.walkhighlands.co.uk/cairngorms/loch-an-eilein.shtml

Our survey route took us all around the loch, through some areas of remnant caledonian pine forest.

We also climbed up to the nearby peak of Ord Ban where there were great views of the surrounding Cairngorm hills.

Craigellachie NNR

I have been a little re-miss in updating my blog as the days have been very busy and the Wifi signal patchy, so I will try and keep posts to a short summary of where we have visited and what I have seen. 

Craigellachie NNR is a place that made a positive impression on me. We were fortunate enough to have a Mountain Ringlet transect at the top of the hill, so had to walk through the reserve to get there. Although we weren't successful in our butterfly hunt that day, the site was lovely.

http://www.walkhighlands.co.uk/cairngorms/craigellachie.shtml

Parking is easy at the Youth Hostel in Aviemore, where there is also a display board just inside the building providing information about the reserve. There are various well-marking trails through the lower wood, extending up to a view point with great views of the Cairngorms. 

Although its a reasonable climb up the hill, it is worth the effort.

Butterflies and Climate Change

At the start of June I started a three month summer job as a Field Assistant with the University of York. I am helping to collect field data for a research project investigating the impact of climate change on butterflies, specifically if the range of certain butterflies is changing.

Our target species are the Northern Brown Argus, Large Heath, Scotch Argus and Mountain Ringlet. Each of these has specific host plants that are needed in their habitats, so as well as carrying out a butterfly transect we also have to do plant surveys for species such as rock rose and cotton grasses. Split into small teams, we each survey several sites a day. These are 1km squares where the butterflies have been previously seen, and a similar project surveyed for them ten years ago.  Overall there are nearly 500 sites to be covered over two survey seasons, across the north of England and Scotland.

So far we have spent two weeks based in Cumbria where we visited sites mainly around the Arnside & Silverdale areas, but also commuted down to the Forest of Bowland.  I then spent a week based from home, travelling out to survey sites on the North Yorkshire Moors, Derbyshire Dales and South Yorkshire peat moors.

We are currently in Scotland where we will be for the next two months. This weeks I have been based near Ullapool, and we have surveyed sites in north west Scotland. The area is remote and the scenery is amazing. Of course, butterfly surveys are weather dependent and this week has been a little challenging, but we have managed to survey all nine sites and found butterflies on all of them. We did get rather wet today though!

As well as looking for butterflies, it has been a chance to see some amazing wildlife and improve my botany skills, and I'm looking forwards to exploring some more areas in the coming months.

Bat Activity Transects

On Friday evening I accompanied the West Yorkshire Bat Group on a trip to Rodley. We were joined by some staff from the Canal and Rivers Trust, and the aim was to identify the species of bat in the area, and get an idea of abundance/activity levels, to inform conservation in the area.

We met at Rodley Nature Reserve and split into two groups. I joined the 'grassland' transect group and we walked the transect route in daylight to ensure we knew where we were going. This proved a good idea, as the route was steep and tussocky in places, and it was difficult to navigate through the scrub and overgrown vegetation down by the river. It was almost dusk when we reached the far end of our transect, so we decided to start there and work backwards, concentrating on the tow path and making incursions into the grassland/scrub rather than risk injury navigating through the undergrowth in the dark.

Rather than the emergence surveys I have helped with in the past, this was a chance to experience another survey method. We walked a set transect, and at key 'listening points' we stopped for 3 minutes and made a note of the species seen and/or heard. Recordings were also made for later analysis. (We did also note down anything encountered whilst walking between the listening points). 

Our first bat of the evening was a noctule - a large, bird-like shape flying high in the sky. Noctules made several appearances through the evening, though the most common species encountered were common pipistrelles with a few soprano pipistrelles also heard.

After the survey, I put my new found QGIS skills into practice and prepared a map of the route and listening points. A most enjoyable evening with good company, and hopefully producing some useful and informative results.

Awesome Ecology

Yesterday was rather hectic and tiring but I got chance to practice several different aspects of ecology culminating with an amazingly batty experience!

The morning started early as I had to go and retrieve bottle traps set out the night before around a local pond. 32 traps had been set up in an area where we had previously seen great-crested newts and evidence of their egg laying.  Given the number of newts we had seen on site whilst torching, the numbers trapped were disappointingly low (just two plus a male smooth newt) but we did get chance to examine a lovely mature pair of great-crested newts that were caught.

In the afternoon I went for a walk around Askham Bog nature reserve in York to practice my botany skills. I met up with another member of the Yorkshire Naturalists Union, and it was good to bounce ideas off each other, especially so early in the season when leaves and flowers are just starting to appear.  We saw many common species and a few less common ones, including Wild Angelica and Gypsywort.

There were also some common species that caught me out. A shrubby tree that I assumed was elder was, on closer inspection, Guelder Rose (Viburnum opulus). I have only ever seen this in a hedgerow so wasn't aware of what the wood looks like, and the budding leaves form a similar 'pineapple' shape. Those that were a bit more developed though were clearly forming into a maple-shaped leaf, with very early flowers also developing.

We also stared at an emergent aquatic plant for ages, trying to convince ourselves it was something unusual. I then went back to my first thought which was that it was a type of bitter-cress, which led to the revelation that it might be Cuckooflower (Cardamine pratensis). Indeed we found another version that was a bit more developed and the pink flower buds were more obvious. I am sure things will all be a bit easier to identify in a few more weeks time!

We saw lots of birds on the site including Great Tit, Blue Tit, Coal Tit, Dunnock, Robin and a Grey Heron, with a roe deer also putting in an appearance across the marsh.

The day finished with an amazing evening of bat watching at Nostell Priory near Wakefield with the West Yorkshire Bat Group.  All nine species of bat found in West Yorkshire are believed to be present on the site, so I hoped to get some experience of other species. We arrived in early evening to allow time to walk around the site and look for visual signs, before getting into position for the dusk emergence surveys at three locations: 

1. A large amount of droppings were found below a large tree with several hollows in the trunk; these were thought to be noctule droppings as they were quite large and angular, and like all bat droppings were very dry and crumbly. The tree was the first of the allocated viewing points.  
2. We then moved onto a stone archway which had numerous cracks in the stonework, and indeed a small bat, believed to be a crevice-dwelling pipistrelle, was found in a cavity during a torch inspection. A few people stayed behind to watch this area.
3. The third survey point was an old building within the gardens. There were numerous possible access points around the shuttered doors and windows, and potentially underneath roof tiles and lead flashing, though the walls themselves were robust.  This was considered to be a potential brown long-eared roost due to the void spaces in the building.

As it was still some time until dusk, some of us wandered back to the tree to see if there was any action. There was lots of 'chattering' from the bats within the tree but nothing to see.  After a few minutes of watching and waiting in silence, bats started to pop out of the holes in the cavity. It was still light and we got a good sight of them flying out. We counted 14, coming out of different holes, that seemed to fly straight out over our heads towards the lake.

We decided to go back to our assigned positions at the building, which needed more pairs of eyes on it. Around dusk we started to get pipistrelle readings (common and soprano) which were frequent as they foraged in the trees around the building. Unfortunately this made it difficult to focus on the task in hand, which was the possible emergence of brown long-eared bats from the building. As they have a fainter call and emerge later, this tests the senses of sight and sound to the limit. We waited for some time as it got darker and colder.  Nothing appeared to come from the building, so we headed back to the tree.

During the walk back past the lack I picked up really strong signals at 26 kHz which would be consistent with noctule bats. By the time we arrived, 150+ bats had now emerged from the tree, and were swarming in the area. It was almost fully dark, though with strong full moonlight, so you could just see the numerous black shadows flitting by. It was an amazing experience to just stand there so close to the bats and they swooped silently in and out of their roost. Definitely a night to remember!

Urban Botany #2

I did the same walk to the shops today but picked up some different flowers to examine. My research was somewhat hampered by the fact that I seem to have misplaced my copy of Francis Rose :(

The first specimen is an Early Dog Violet (Viola reichenbachiana). This is distinguished from the sample I found yesterday (Common Dog Violet) as the 'early' version has a darker purple spur rather than it being pale/cream coloured.  The veins within the flower are also shorter and straighter. Like the 'common' version, this plant has pointed sepals and hairless heart-shaped leaves. I found a good comparison of the species on this website.

The second plant found today is a forget-me-not. I believe it is a Wood Forget-me-not (Myosotis sylvatica) though this is very hard to tell apart from the Field Forget-me-not. Both are quite hairy with pretty pale blue flowers with a yellow centre.

I also found a speedwell (Veronica sp) with its distinctive four purple petals and two anthers [not pictured]. I think the version I found is Ivy-leaved Speedwell (Veronica hederifolia sub species hederifolia).  Although it does not seem as hairy as some of the photographs I have seen, it does have distinctive blue anthers.

Finally, I picked a very common plant but the first I have seen in flower this year - Cow Parsley (Anthriscus sylvestris). This has umbels of tiny white flowers, each with five petals. It is distinguished from the very similar Fool's Parsley as Cow Parsley is slighly hairy, particularly on the back of the leaves, and the bracteoles are much longer and more obvious in Fool's Parsley.

Urban Botany

As Spring starts to appear, so too do the flowering plants. I have been starting to notice these around my estate and on the walk to my local shops I plucked a few specimens to take home and identify. I was fairly sure I knew what they were, but wanted to make sure - it's good to keep botanical knowledge up-to-date, especially after winter when it inevitably fades slightly with lack of practice.

The violet is likely to be Common Dog Violet (Viola riviniana). The leaves and flowers do not all come from the same location at the root; heart shaped leaves are sparsely hairy; flowers have mid-purple petals with a cream spur and darker purple branched veins; sepals are pointed and the flower has no obvious scent. The leaves are stem are tinged red/purple though so this may be a garden variety.

Shown in the pot is Variegated Yellow Archangel (Lamiastrum galeobdolon ssp argentatum). This is a non-native varient of Yellow Archangel. It differs as the leaf edges are more regularly toothed, and the colouring is variegated with silver which turns a chocolate brown colour over winter. The native plants is very similar but has just a few flecks of silver and never has the chocolate colouring.

The trefoil plant with the yellow flower is Black Medick (Medicago lupulina). This has the three leaves typical of the trefoil family. The leaves are hairy and have a distinctive point at the tip, as shown opposite. Once the flowers die off, distinctive black seed heads are left.

Also common at this time of the year is a weed common in my garden, Wavy Bittercress (Cardamine flexuosa). This is the straggly plants (second from left in bottom photograph) with narrow leaves and small, white four petalled flowers. It has long seed pods and is one that I will be digging up before it can spread to my mini allotment patch!

The last once shown is, I think, Wall Lettuce (Mycelis muralis) a dandelion type plant that has tiny yellow flowers later in the year, with the leaves heavily clasping the stem.