I thought I should resurrect my personal diary. It has been over two years since I posted anything and it has been a particularly busy two years. I thought I should start off by summarising how butterflies did in East Lothian in 2018. I collate the records from the Countryside Rangers and a number of volunteers and it is interesting to see how each species has fared over the years.
2018 was a fantastic year for butterflies. The long, warm summer was a great help, although the poor previous summer probably impacted on some species. It was a bit of a slow start to the year, with cold weather continuing throughout March, including the "Beast from the East" and then a cold start to April. The warm weather arrived in mid-April, resulting a sudden explosion of butterflies! Spring populations were about average, but the later summer populations were considerably larger than we have seen for a number of years.
We had the same number of people contributing records in 2018 as we had in 2017, so it is interesting to compare the number of butterflies seen. In 2017 I received 2,119 ad hoc records, totalling 7,527 butterflies. The 2017 transects recorded 2,008 butterflies. In 2018 I received 2,608 ad hoc records, totalling 12,646 butterflies and the transects added another 4,229. A considerable increase in the number of butterflies seen, which we can be pretty confident was a result of the great weather we had in 2018.
Small Tortoiseshell, Aglais urticae
The first butterfly to be seen in 2018 was a Small Tortoiseshell, which was seen on 22nd February at Torness. I didn't receive any more Small Tortoiseshell records until April. After that they were seen regularly, but not in any great numbers. The number seen in 2018 wasn't far below the average over the last few years, but they are certainly declining in numbers. When so many other species did so well in 2018, we would have expected them to do better. Interestingly, despite the good weather some Small Tortoiseshells were found to be hibernating as early as the 4th August.
Peacock, Aglais io
The first Peacock to be seen was on 8th March. There were very high numbers seen towards the end of April once the weather warmed up. These were the butterflies that had overwintered from 2017. After the usual lull in numbers the 2018 generation was seen in enormous numbers from the end of July with Peacocks being seen right through into November.
Green-veined White, Pieris napi
The first Green-veined White was seen on 17th April. I had thought that there didn't appear to be very many about in 2018, but other people saw plenty. There was an enormous spike in population in late July and they were recorded in higher numbers than in any of the previous five years. I suspect that a lot of Green-veined Whites go unrecorded because of their similarity to Small Whites, often being noted as fly-by whites.
Small White, Pieris rapae
Small Whites had an amazing year. The first one recorded in East Lothian was on 18th April and the spring population was as we would normally expect. However, in late July there was a mass emergence. I remember driving from Haddington to Macmerry and seeing hundreds of Small Whites drifting across the road. I received several other similar reports that day. We ended up with records of almost 3,500 Small Whites in 2018, nearly five times the number of the previous best year.
Red Admiral, Vanessa atalanta
The 18th April was also the day the first Red Admiral was recorded in East Lothian. They had done fantastically well in 2017 and hopes were high that they would manage to survive the winter and be seen early in the year. However, very few were recorded until July, which is when we often get an influx of migrants. Those migrants clearly enjoyed the sunny summer and went on to produce a good summer generation. Nothing like the previous year, but still a lot more than we would normally see.
Large White, Pieris brassicae
As with the previous two white species, the Large White had a fairly average spring generation, but then an enormous summer generation. The first record I received was on the 19th April and towards the end of July there was a huge spike in numbers. We ended up with about three times the number of records that we would normally receive.
Comma, Polygonia c-album
The Comma has gradually been building up in numbers since it was first recorded in East Lothian in 2001. However, the poor summers of 2016 and 2017 did them no favours and their numbers were very low for a couple of years. It was encouraging to see numbers pick up again in 2018 and with a bit of luck they will continue to do well. The first Comma was seen on 19th April, they peaked in numbers in the middle of August and were seen through until 15th November.
Orange Tip, Anthocharis cardamines
The Orange Tip is usually seen in reasonably consistent numbers. However, in 2018 we had more than double the usual number of records. The first record was on 20th April and they were seen until the middle of June. However, there was one very late record on 22nd July. It is interesting to speculate why that individual emerged at that time. Presumably it was a late emerger, rather than a second generation.
Speckled Wood, Pararge aegeria
2018 marked the tenth year of the Speckled Wood being recorded in East Lothian. During that time it has expanded its range to almost the entire county. 2018 was its best year yet and interestingly it was the spring population that did particularly well. The first record was on 24th April and they were seen right through until 25th October.
Green Hairstreak, Callophrys rubi
Green Hairstreaks live in a few scattered colonies around East Lothian. It is difficult to know how well they did overall in East Lothian in 2018, as many of the colonies are in remote locations in the Lammermuir Hills which were not checked. The regularly recorded site at Saltoun Wood had suffered a fire sometime in the preceding months, which impacted considerably on that colony. The exciting news, though, was that Green Hairstreaks were rediscovered at Hopes. This is the first time they have been recorded there since the 1980s.
Small Copper, Lycaena phlaeas
The Small Copper isn't a butterfly that is normally seen in large numbers, most often being seen individually, as males aggressively defend their territory or chase after females. In 2018 there were regular records of more than ten being seen. It was certainly the best year I can remember for Small Coppers. The first record was on 8th May and they were seen through to 2nd November. The most exciting news is that that we had a very obvious third generation in 2018, which we haven't previously seen here.
Wall Brown, Lasiommata megera
The first record of a Wall Brown in 2018 was on 11th May. The Wall Brown has continued to increase in numbers year on year since it was first recorded here in 2010. As with many other species, the spring population did pretty well, but it was the second generation that did particularly well. In previous years we have found the odd pioneering individual exploring further afield, but this year there did appear to be an expansion of the range of this butterfly with it being found in numbers at various sites where it hasn't previously been recorded.

- Distribution of Wall Browns in 2018 compared to previous years.
Small Heath, Coenonympha pamphilus
The Small Heath seems to have two overlapping generations a year, although it is not really possible to separate the two generations. There also seems to be quite marked differences between different sites, and in my experience those in John Muir Country Park appear to finish quite a few weeks before those found in Aberlady and Yellowcraig. Most years there are also a few quite fresh-looking individuals later in the season making us question if there could be a partial third generation. 2018 wasn't particularly different from previous years, with the first record being on the 18th May and the last hanger-on being seen on 23rd September.
Common Blue, Polyommatus icarus
As with most other species, the Common Blue did very well in 2018. Numbers weren't dramatically higher than normal and it is interesting to speculate why some species did so much better than others. Possibly it may be to do with how their food plants coped with the hot, dry summer. The first Common Blue was seen on the 29th May and the last one was seen on the 7th September.
Painted Lady, Vanessa cardui
Painted Ladies were quite late to arrive in East Lothian in 2018. There were a couple of records in early June, but it wasn't until later in July that they were seen in any numbers. 2018 turned out to be one of the best years we have had recently for Painted Ladies.
Meadow Brown, Maniola jurtina
Meadow Browns were the only butterflies that didn’t do particularly well in 2018. I think that they suffered from the poor weather the previous summer. Although numbers were higher than last year, they were lower than we would normally see. The first record in 2018 was on the 12th June and they were seen through until the 29th August.
Ringlet, Aphantpopus hyperantus
Ringlets did reasonably well in 2018, but not as well as many other species. I think they may also have been a victim of the previous poor summer. The first Ringlet was recorded on the 18th June and their short flight period lasted until the 5th August. It will be interesting to see if the great weather of 2018 will allow numbers to bounce back in 2019.
Dark Green Fritillary, Argynnis aglaja
We don't tend to see a lot of Dark Green Fritillaries and they are generally limited to coastal sites and one or two valleys in the Lammermuir Hills. Numbers in 2018 were about average, but they had a terrible year the previous year, so it was good to see them bouncing back.
Northern Brown Argus, Aricia artaxeres
I am only aware of four places in East Lothian where Northern Brown Argus occur. Three of those sites are very small and vulnerable. Because of this I don't receive many records of Northern Brown Argus, so it is difficult to assess how they are doing. However, at one site near Dunbar, despite several visits only one Northern Brown Argus was recorded. Maybe this is a butterfly that we need to look at a bit more closely in the future.
Small Skipper, Thymelicus sylvestris
The Small Skipper has been increasing in number year on year, since it was first discovered in East Lothian in 2011. Unsurprisingly, 2018 was its best year yet. They were initially found along the coast in the Aberlady and Gullane area, but in more recent years have been found in the Lammermuir Hills, lowland woodlands and various areas of rough grassland across the county. The first record in East Lothian was on 21st June and they were seen through to 27th August.
Grayling, Hypparchia semele
I am only aware of three sites where Grayling are found in East Lothian. One of these is very remote and I didn't receive any records from there this year. The other two sites are close to Prestonpans and one of these colonies is about to be lost to a housing development. There is an exciting project currently underway to create a new habitat to try to relocate one of these colonies. The first Grayling was recorded on 27th June and they were seen through to 21st August.
I didn't receive any records for
Large Skippers in 2018, but I suspect they will be out there somewhere, unlike
Holly Blues, which I fear have died out in East Lothian, having not been recorded here in the last two years. I didn't receive any records of
Small Pearl Bordered Fritillaries from East Lothian, either, but I am sure they would have been out and about somewhere in the Lammermuir Hills. Given the prolonged period of great weather I was surprised that we didn't receive any records of
Clouded Yellows or any other unusual migrants.
Many species were late to appear because of the cold weather, which lasted into April. It was interesting to note that the hot weather didn't result in prolonged emergence and may have shortened the time that each generation was around because they all emerged quite close together. In contrast, poor weather can extend the flight period, because butterflies have to spend time sitting out the rain, rather than flying around, potentially damaging their wings.
I would like to extend a big than you to everyone who sent in records last year. We have a great mix of recorders in East Lothian, some of whom record butterflies while they are out walking or going about their work, and others who go out specifically to look for butterflies. It all adds up to a great lot of records and there was hardly a day between April and October when I didn't receive a record.