Friday 31 July 2009

Butterflies rule - OK!

My late Dad would have enjoyed the last month. Despite living in Lancashire he had a “like to see” list of plants in his head that he had developed from books such as Highland Flora by Derek Ratcliffe and Wild Flowers by John Gilmour and Max Walters. When Janet and I moved to the Isle of Rum and then to Loch Garten the chance to fulfil his wish started to become a reality because some of his wish plant list could only be found in the Highlands. Many of the important Rum plants were really out of Dad’s reach, involving long walks and mountain tops, but our move to Loch Garten opened up the world of the rarer pinewood plants, creeping lady’s tresses, lesser twayblade, perhaps twinflower but probably not one-flowered wintergreen. Over time Abernethy almost provided them all but we had to travel to Culbin Forest and Golspie to search for and find one flowered wintergreen. In 1910 the wintergreen had been recorded in several places “in pinewoods at Loch Mallachie” (The Flora of Moray, Nairn & East Inverness-shire by Mary McCallum Webster), but despite many searches I have failed to re-find it there. In 1990 a survey worker stumbled on a single patch of about 30 plants at the end of a day's mapping and two years later a few more plants were found nearby – never to be re-found. Plants reported by a visiting Dipterist in the 1990s have never been re-found, and the fortunes of the original plants have ranged from a few rosettes of leaves some years to 50+ plants and a few flowers in others. 2009 has been one of the latter type years with 40+ plants producing about 25 flowering spikes, and a site near Grantown on Spey that I have been monitoring produced a few flowering spikes despite a heavy predation event during February by marauding sheep. Checking these sites this year reminded me just how small the basal rosette leaves seem to be in this area, individual leaves in the range 5-10mm and the whole rosette being no more than 15-20mm wide in many cases. The evening of the 12 June therefore turned out to be quite memorable as I made my way back to the vehicle after a botanising session along the River Nethy. Making my way up a damp runnel something white caught my eye and as I leaned on my Leki poles for a better look I realised that I was looking down at a flowering spike of one flowered wintergreen (Moneses uniflora). In the gathering evening gloom out came the GPS to record the spot along with the camera to try and get a photo, and so as not to “loose” the spot, a short piece of red and white tape was tied to the vegetation. A wider search found another flower and a couple of metres away, 8 flowerless rosettes. Without the two flowers it would have been impossible to have found the plants. Let’s hope the next find isn’t another twenty years away!

BTO Atlas surveys are also good for providing plant records! Yet again, wandering along recording birds something else of note was found. On the same day that my BTO survey took me close to the 5-spot ladybird site, I also popped my head in to a young patch of Scots pine woodland that had become established on a section of old river shingle. A couple of lesser twayblade leaves caught my eye and then another with a huge flower spike, and another, and another………… the wood seemed to be full of twayblade leaves and flowers. There were so many that it wasn’t possible to walk in sections of the woodland for fear of trampling the plants, but a quick estimate from checking from the edge of the trees was that there was more than 1000 plants and possibly as many as 2000. An amazing sight particularly when the small patch of trees didn’t look like anything special from the “outside”. Elsewhere in Abernethy this wee orchid seems to be having a very good year with many more flowering spikes being seen in areas of the forest where it has been known for many years. And it happened again, in a similar patch of young pines, also on ex River Nethy shingle, another gathering of 1000+ twayblade plants. Amazing.

I hadn’t realised just how diverse plants and insects can be on river shingle, and the River Nethy has had a few visits when the sun has shone. Two more sites have been found for the 5 spot ladybird, two bees were new to Abernethy and a very striking small moth, flitting around on the freshly emerging thyme flowers evaded two attempts to catch it in a tube, so as a last resort I had to rely on the camera, and though the picture was taken from a distance, it did allow a record to be made and the enlarged picture to be sent to Tom our local expert for identification. The moth turned out to be one of the bigger “micro” moths, hence the reason I couldn’t find it in my own moth book, and it goes by the name of Pyrauta cingulata. It hasn’t been recorded in this area before and was quite an amazing find. For more information see http://ukmoths.org.uk/show.php?id=970 where the information suggests the moth is found on the coast! Well there was water, sand and its food plant wild thyme.

This wasn’t the only species I found this month that really belongs to the coast. Towards the end of one of the weekly butterfly transects in late June I saw what looked like a 6 spot burnet moth. Unlike my river Lepidoptera encounter, this time I was well equipped complete with butterfly net and with a quick waft of my arm, the moth was in my net and then in a tube for a better look. Sure enough, I was looking at a 6 spot burnet, Tulloch Moor is some way from the coast but not that far from the orchid field site where I had recorded it in 2008. I let the vice County recorder know of my find and he visited a few days later to find there was a well established colony on that bit of the moor, linked to the bird’s foot trefoil flowers on the burnt heather patches, numbering over 100 individuals. He also located cocoons from 2008 showing that the moth had been around for more than a year.

The 6 spot burnet moth was also seen at the orchid field site again this year but that wasn’t the reason for my visit. With the permission of the fields owners I had made a count of the orchids in 2008, and with their permission I was back to repeat the count again this year. This small field, right next to the B970 (right), is considered the best site in Scotland (and possibly Britain) for the number of flowering spikes of lesser butterfly orchids. Past estimates put the population at several hundred and my hurried count, after the frost, last year give a total of around 700 plants. This year I was determined to do a more logical count, line transects right across the field with red and white tapes for accuracy/guidance, and with a hand-held tally counter to take care of the running total rather than remembering 101, 102, 103 etc in my head. It turned out to be a full afternoon of a task, particularly when there was also a small population of small white orchids also to count. Looking into the field from the road there seemed to be a lot of flowering spikes and at the end of the count I wasn’t too surprised to find the total to be over 1200 plants. Throw in a couple of hundred small whites and a few thousand fragrant orchids and there can’t be many sites in the UK that can boast something similar. My hat goes off to the Fletchers for managing the grazing of the field so sympathetically as to maintain this amazing annual botanical extravaganza. A bonus for the day was finding a nice colony of flowering common wintergreen plants (Pyrola minor), many of which were in flower. Usually, there are lots of basal rosettes of leaves with just a few flowers, but this patch was just about the opposite with lots of mini-towers of white waxy flowers popping out of the vegetation.

What about the real butterflies? The weather during June and into July hasn’t been the best for butterflies and in common with other parts of the country blinks of sun have been followed by drinks of rain. I would say that numbers of butterflies in the Firwood garden are down on previous years, probably due to the poor weather during the last couple of summers. Red admiral, painted lady, common blue, large white, small tortoiseshell and ringlet have been seen in amongst Janet’s amazing floral displays, but mainly as singles rather than regulars. The weekly butterfly transect has been good when the sun has been out for the whole of the one and a half hour visit, but for most it has been a mix of sun and cloud and quite a bit of wind. Not ideal. However, the requirement is one transect walk per week so TV weather maps have been studied to try and aim for the best day for the walk. Chronologically the season has so far produced the following butterflies:
Small tortoiseshell
Peacock
Green-veined white
Green hairstreak
Orange tip
Small pearl-bordered fritillary (right)
Ringlet
Small heath
Large heath
Meadow brown
Common blue
Red admiral
Painted lady
Dark green fritillary
Scotch argus.
The real eye-opener has been the high numbers of ringlets, from a first record in 2006, 44 were counted during one visit in July and to date, this has to have been the most numerous butterfly. For details of all previous surveys see http://www.ukbms.org/site51/description.htm and click on Species count. In addition, Butterfly Conservation have teamed up with the BTO to ask those recorders involved in carrying out the Breeding Bird Survey (one kilometre squares surveyed annually - see earlier diaries) if they would visit the recording squares again, monthly, between June and August to record butterflies. Great if your breeding bird square covers nice flowery meadows but not so great when your square rises to over 500 metre asl (left). However, nil or low counts are just as valuable as massive counts, but I do feel my square will be lucky to locate more than a couple of species. Watch this space. A bonus from the first visit was a male hen harrier and a family of jays, a rare bird in this part of the world, good records for the breeding bird atlas.

A bit late for breeding but there have been a few unusual bird records over the last few weeks. A singing whitethroat was found on the butterfly transect, but had gone a few days later, two wrynecks obviously heading for somewhere else as they were only heard once each, and a couple of quails one locally, where one has been heard in other years so a possible breeder and one near Blair Atholl during an interesting visit in late June. The weather map had shown full sun throughout Britain for the day of the Blair Atholl visit so I headed south for the day to look for the small solitary bee Osmia inermis, the one we built a few rock nesting sites last September. The more local weather forecast hinted at early morning mist in the Atholl area first thing, burning off by late morning. As I left the house the coolness of a clear night was giving way to a hot sunny day. As Dalwhinnie passed by on the starboard side and Drumochter Pass beckoned mistily in front I was hoping the weather folk had got their calculations correct! No sun and these small bees don’t fly and that would be a waste of 120 miles. As I left the A9 by the House of Bruar, the mist had gone but the clouds remained low, but it was only 10am. Boots on and off up the hill when the “whit, whit, whit” of the quail stopped me in my tracks. As I climbed the track I was amazed at the richness of what, from a distance, looked just like plain old heather moorland. But this wasn’t any old moorland, this was lime rich moorland and famous and designated as an SSSI for a land snail, round-mouth whorl snail (Vertigo genesii) I think. Orchids, bird’s-foot trefoil, clovers and then large round yellow flowers on long stalks appeared, globe flowers, masses of them running up the hillside, an amazing sight (left). The first area of rock bee nest sites was reached and the cloud overhead remained stubbornly solid. A few bumblebees were on the go visiting the trefoil and clover flowers, but with the temperature quite low there was no chance of seeing the solitary bee. The next hour was spent checking the rock nest sites, none of which had been used. Just beyond the last site was a small burn and I could see lots of yellow flowers along its sides so I went to investigate. Starry saxifrage, yellow mountain saxifrage, the insectivorous butterwort in full flower and a small white flower growing in amongst the bog asphodel leaves (right) turned out to be its close but much rarer relative, Scottish asphodel, a nice find to brighten my sunless day. I followed the burn up the hillside towards a natural rock outcrop which could hold out future potential nest sites for the Osmia bee, and close by was a natural stone wall, with again many potential nest sites, something not found by earlier surveyors. It was 4pm and time to retrace steps and head back to the car and I noticed the first break in the cloud cover. By the time I had reached the globe flowers the sun was beating down but all a bit late to start standing by the patches of bird’s-foot trefoil waiting to see if the wee bees would visit to feed. Next year……
Enjoy.

With best wishes
Stewart & Janet

A recent visitor to the Osprey Centre - watch Countryfile



The joys of late evening botanising, Ryvoan Pass & Cairngorms

All photos © Stewart Taylor