East Lothian Butterflies 2021 Part 1

The number of East Lothian butterfly records was quite a bit lower in 2021 than in previous years. This was partially due to the additional work load that Covid 19 placed on the Countryside Rangers and, to some extent, because I am no longer living in East Lothian. I didn't receive so many records from volunteers this year, maybe because they were making the most of the reduced lockdown restrictions. However, it turned out to be a very interesting and exciting year for butterflies in East Lothian, possibly a record year!

It is a little odd reporting on East Lothian butterflies now that I am living in the Borders. I usually get an impression on how things are doing when I am out and about, but things can be very different here compared to East Lothian. I did keep a note of butterflies that I saw when I was in East Lothian on site visits, but frustratingly those dates often didn't coincide with decent weather!

So, in 2021 we received a total of 1,546 records totaling 7,996 butterflies. This is a higher number of butterflies than were recorded in 2020, but about half the number of previous years.

2021 started off very cold and frosty. Despite a warm spell at the beginning of April frosts continued into May. Thereafter the weather wasn't too bad, but the earlier cold spell appeared to impact on some butterfly species.

Despite the weather, the first butterfly to be recorded in 2021 was a Small Tortoiseshell seen at Aberlady on 17th February. This species did very well during the spring, but there weren't as many as usual later in the summer. This year I didn't find any Small Tortoiseshell caterpillars, despite looking in likely spots, which is unusual. I suspect that the late cold spells must have limited breeding opportunities for them.

The first Peacock was seen on 26th February sunning itself in a skip in Dunbar! Like the Tortoiseshells, they appeared to have a poor year, even taking account of the limited number of records received. This corresponded with how few I saw at home on my Buddleia later in the summer.

It wasn't until the 16th of March that we saw the first Comma of the year. Unfortunately, 2021 was one of the worst years I have known for them. They are not normally seen in large numbers, but this year we only recorded 24 individuals. On average over the last 8 years we have seen over 75 Commas each year.

The first Small White was recorded on 3rd April. They had a reasonably good year, but like the species above the summer generation wasn't as big as normal. It is interesting that the Green-veined White, that has a similar life cycle, did much better later in the year. The Green-vein is a species that I associate with damper areas, so possibly they are better able to cope with poor weather. The first Green-veined White was recorded on 17th April and they were seen through to 7th September.

It was exciting to see the Holly Blue doing well again in 2021. The first record was on 10th April and over the season I received records of 101 Holly Blues. They were seen in all of the locations where they were seen the previous year and don't appear to have expanded their range further. However, this is encouraging, given that many other species struggled in 2021.

The first Speckled Wood was seen on 11th April. Their numbers were lower than normal in the spring, but they more than made up for it with very high numbers seen in late August and September. It was good to see their numbers bounce back after a poor year in 2020.

Orange Tips first appeared on 12th April. Unfortunately, they had a very poor year, probably because their flight period coincided with the cold weather. Of course the cold weather may also have meant that fewer people were out looking for butterflies, so hopefully things weren't as bad as they appeared and we will see them back in good numbers again this spring.

Large Whites made an appearance from 21st April. They didn't do very well in the spring, but unlike its smaller cousin, the summer population was relatively high. It isn't a butterfly that is ever seen in large numbers, but 2021 was one of the best years we have had.

Red Admirals had a particularly poor year. The first record of was on 22nd April and only one more was seen in May. June was better, but we didn't see the usual big influx of migrant butterflies. As a result the summer population was lower than we have seen for the last few years.

The first Wall Brown was recorded on 30 April and they went on to have a fantastic year. Over the last ten years, since they first arrived in East Lothian, they have increased in number year after year. 2021 was by far the best year yet with records of 663 butterflies reported.

Small Heaths had a very good year. In fact I received more records of them in 2021 than in any previous year. They had a short season, first being recorded on the 17th May and being seen until 5th September. It is said that in Scotland there is only one generation a year, but further south in England there are two generations a year. It is difficult to understand what is happening here with them being seen over such a long period and it is tempting to think we get two generations.

Common Blue had a bit of a slow start to the season, with the first record being received on 30th May. However, their numbers soon picked up and they ended up having a very good year.

2021 wasn't a good year for Painted Ladies. The first record wasn't until 5th June, which is a lot later than usual and I only received records of 38 individuals. I suppose that when you think that these butterflies start off in Northern Africa and migrate over two or three generations before they arrive here that it isn't surprising that some years very few make it. They will need good weather and food sources throughout their journey to be successful.

I will continue this on the next post...