East Lothian Butterflies 2025 part 1

I collect the butterfly records from the East Lothian Countryside Rangers and about 40 volunteers. At the end of the season I put together an annual round-up that I send to the volunteers to let them see how their records fit into the big picture. Below is an edited version.

2025 was pretty dry and sunny in East Lothian, but there was often an easterly wind keeping the temperatures down. The general lack of rain and the wind caused the vegetation to dry up, particularly in coastal areas.

We had a couple of very early records. Firstly, a Speckled Wood that was seen on 15th January in Butterdean Wood. I can only assume that it had crawled into a nearby greenhouse as a caterpillar last autumn and was tricked into thinking that spring had arrived.

The next butterfly was a Small Tortoiseshell, which was seen on 28th February. Maybe this wasn't such a surprise as they spend the winter hibernating as adult butterflies, so can make an appearance on a mild day.

There was then a flurry of Small Tortoiseshells and Peacocks on 6th March. Both species had a fairly average year, but at least Small Tortoiseshells bounced back from last year's low numbers.

There were a few Red Admirals seen in March, indicating that they may have survived the winter here. They went on to have an amazing year, with us recording about three times the average number.

The first Comma was seen on 15th March. They went on to have a great year, particularly later in the season, and I received the highest number of records since I started collating them in 2008.

A few days later a Painted Lady was spotted in North Berwick. They also had a good year, with 220 records - a big improvement on last year's 14! Their numbers can be really variable. I would suggest the normal annual average is under 100 records, but the figures are skewed by the 2019 invasion when I received 5395 records!

All four white species had an amazing year. For Orange Tips, Green-veined Whites and Large Whites it was by far the best year since I started recording the butterflies. 

Small Whites also had a fantastic year, way above average, but not quite as high a number as was seen in 2018.

Speckled Wood numbers picked up in April and they also had a very good year. I received records of 1608 of them, which is the second highest number since they reappeared in East Lothian in 2009.

Small Coppers had a fairly average year.

The same could be said for Wall Brown. Their numbers look fairly average, but when you look at when they were seen, they were almost exactly two weeks early and there was a small third generation towards the end of September, with the last one being seen on 7th November.

I will continue this on my next post.

Of Caterpillars and Chrysalises Part 2

Continued from my previous post.

I can’t believe the number of eggs I have found this year of Large Whites, Small Whites and Green-veined Whites. There have been a lot of adults flying around and my Nasturtiums have been covered in eggs. 

The Large White lays its eggs in batches on the underside of the leaves.

The other two species lay their eggs individually anywhere on the plant. They have also been laying eggs on a Rocket plant growing in our patio and on Bittercress and Garlic Mustard.

I tried to photograph some Large White eggs and various stages of their development as caterpillars, but there were so many different batches of eggs I couldn’t keep track of which were which.

There were so many caterpillars that some of the Nasturtiums were completely stripped of leaves. I tried to pick leaves from other plants, but discovered that most of them had new batches of eggs on them. So, I resorted to buying bags of Curly Kale to try to keep the caterpillars alive! I have never seen so many caterpillars!

Once they were ready to form chrysalises they crawled up the wall of the house to find a sheltered spot.

Unfortunately, a few were parasitized by Braconid wasps. Presumably the adults had laid eggs inside the caterpillars at some point and the larvae burst out of the chrysalises to pupate.

And the Bluetits learned where to look for the caterpillars, flying up to the wall and picking off the chrysalises. Even the chrysalises that I had thought were safe were picked off by wasps, biting into the chrysalis and managing to prize them off the wall! I was feeling a bit despondent, seeing so many chrysalises perish after I had put the effort in to save the caterpillars. 

However, I needn't have worried. One day I noticed a Small White butterfly emerging from under the Alpine trough. I had a look underneath the trough and there were several more Small White chrysalises under there.

During the late summer/early autumn there have been loads of Large Whites, Small Whites and Green-veined Whites flying around.

On 12th July I noticed a hutchisonii form of Comma laying eggs on the nettles behind my garage. I wasn’t able to look for the eggs for fear of being stung, but on the 7th August, I was walking past the garage when I spied a little face peeking out from below a nettle leaf. It was a Comma caterpillar.

I watched it for a few days and on the 10th August it formed a chrysalis.

Unfortunately, it is now the end of September and nothing has emerged from the chrysalis, so I fear it may have failed.

I was down in my meadow one day in August, when I noticed a nettle bouncing around. I couldn't understand why it was moving like that on a still day. On closer inspection I noticed that the top leaves were stitched together and on top of the leaves was a parasitic Ichneumonid wasp.

I chased the wasp away and investigated further and found a Red Admiral chrysalis inside the nettle leaves. A little later when I walked back the nettle was bouncing around again and the wasp was back. So I decided to pick the nettle and put it in a mesh cage. I thought that in a few weeks I would either have a Red Admiral or a number of wasps! Luckily it was a Red Admiral that emerged from the chrysalis about three weeks later.

I don't think I have ever known such a good year for finding caterpillars and chrysalises!

Small White Chrysalis, Parasitic Wasp

Last year I notice a number of green caterpillars on some Rocket that was growing between the slabs in our patio.

I assumed they were Small White, Pieris rapae, because I had seen adults laying eggs although I couldn't be sure they weren't the caterpillars of Green-veined Whites, Pieris napi.

Later, once I saw the caterpillars were gone, I looked all over the walls of the house for chrysalises, but could only find one Small White chrysalis.

At the beginning of April this year I was sorting out the garden furniture in anticipation of a family visit when I notice a Small White chrysalis on the arm of a garden chair.

Knowing that it wouldn't be safe I carefully removed it and placed it in a jar lined with paper towel inside one of my rearing cages.

About three weeks later I was checking the chrysalises and noticed a number of small insects climbing around on the walls of the cage. I realised that these were parasitic wasps and I found about 15 of them.

When I checked the Small White chrysalis I noticed a neat round hole in it.

I haven't been able to identify the wasps, but I am interested to know more about their life-cycle. I presume that they either lay their eggs into caterpillars or chrysalises and they must develop inside the chrysalis early in the spring. It was the 24th April when I found the wasps, a time of year when the Small White would be either still be chrysalises or would have emerged into adults. Any eggs the butterflies lay would only hatch in early June, about six weeks ahead. I wonder if there is another host that the wasp uses at that time of year.

Happily there have been a lot of Small White butterflies flying around this year, so a good number made it through without being parasitised.

Scottish Borders garden butterflies 2024

We are lucky enough to live in 17 acres of woodland which we have been managing to improve for butterflies and other wildlife. I am developing a wild flower meadow, planted an area of native broadleaves that produce flowers and berries, put in hedges, taken out loads of invasive Rhododendron and planted up various areas with Rockrose and other wild flowers. Our triangle of land is quite a wildlife haven, which in itself causes more challenges. Everything needs to eat, either other creatures or precious plants that I have been nurturing!

It has generally been accepted that 2024 was a lousy year for butterflies in the UK. The Big Butterfly Count confirmed low numbers for most species with record-breaking reductions from 2023 for many species. I have yet to receive all of the record for East Lothian, but my own experience at home here in the Scottish Borders concurs with the national picture.

Although this is only the fifth year that we have been living here I had noticed a pattern developing and numbers of butterflies had been increasing year on year. I can't be sure why that was, but I would like to think it was partially because of the work I have done to manage the habitats here.

In previous years the first butterfly to appear has been the Small Tortoiseshell, which would venture out on a mild spring day to feed on whatever it could find flowering that early in the year. This year, however, I didn’t see any until August and I only saw a total of four all year. I didn’t find any caterpillars either this year, which is unusual. Often I find big clusters of caterpillars on nettles.

Peacocks and Commas are the other two butterflies that over-winter here. At least they both made an appearance this spring, but in surprisingly low numbers. This was particularly disappointing for Commas after I had such a bumper year for them last year. Towards the end of last summer I had been finding caterpillars and chrysalises everywhere, so I expected them to do well. However, this year I only recorded 26 compared to 122 last year.

Despite a poor spring showing the later summer generation of Peacocks did a lot better. The number I saw was only a little lower than average, which is encouraging. Again, I didn’t find any caterpillars, which is unusual.

Orange Tips had a fantastic year here. I recorded 101 of them this year, which is way up on the previous best number of 62. I also saw an unusually high proportion of female Orange Tips.

Despite finding so many caterpillars and chrysalises last year, the number of Small Whites this spring was lower than expected. I did see them throughout the year, though, and ended up seeing 26. This seems a low number compared with the 90s I have seen in previous years, but their numbers do seem to fluctuate considerably from year to year.

I saw seven Large Whites this year, which is about average for this species.

Although I had the impression that there were not many Green-veined Whites around this year, my records show that numbers were only slightly down on previous years. They were more numerous in the spring and the summer generation wasn't so good.

Red Admirals had the worst year by far here. I only recorded 38 in total compared to last year's 474!

Ringlets were here in about average numbers. Not as good as the previous two years, but better than the numbers I had seen before then. There is more suitable ground for them now that we have taken down a large area of Spruce woodland, which has now grassed over and thinned out the trees elsewhere. With the additional habitat it is a bit disappointing that the numbers weren't higher. Certainly higher up the valley where I often walk numbers were well down on previous years.

Last year was really good here for Meadow Browns. This year their numbers dropped back to what I had previously seen here. This was disappointing, as I had thought that Meadow Browns  were appreciating the new areas of grassland. However, numbers up the valley were also considerably down on previous years.

The first Speckled Wood I saw here this year was on 2nd July. Having seen them for the first time here last year I was delighted to see them return, although I had been hoping to see some in the spring indicating that they had bred here. I continued to see them for the rest of the year and ended up seeing 18 - 4 more than last year!

Small Skippers had the worst year since I first saw them here in 2021. They had been increasing in numbers since then, so it was disappointing that I only saw seven here this year. Similarly, in the valley above the house the numbers were lower than normal.

I often chance across a butterfly and think to myself if I had been there five minutes before, or five minutes after I would have missed it. I suppose, though, that there will be hundreds of butterflies I miss because I am not in the right place at the right time. So, this year's lucky spots included one Large Skipper in my meadow. I don't know why I only saw one, as there were a lot in the valley above our house.

As I do most years, I just saw one Small Heath in our meadow. It isn't best suited for these butterflies, so it is odd that most years I see one, just one!!

This year, again, I was delighted to see a Scotch Argus. I just happened to go out to check the Buddleia on a sunny afternoon and spotted a small, dark butterfly. I am still intrigued why I have seen one five out of the last six years here. I am sure there must be a colony close by, which I am yet to find.

Last year I saw my first Wall Brown here in the meadow. This year, I was sitting having lunch outside when a Wall Brown landed on some Marjoram in our patio. They have been slowly working their way in this direction over the last few years.

Disappointingly I only saw one Small Copper here this year. I don't understand why I don't see more as there are plenty of sorrel and dockens growing here for their caterpillars to feed on.

Sadly I didn't see any Northern Brown Argus, Dark Green Fritillaries, Small Pearl-bordered Fritillaries, or Painted Ladies here this year. I saw the first three species in the valley above the house, but in much smaller numbers than normal. This is the second year in a row that I haven't seen a Painted Lady anywhere in the UK!

It is difficult to know exactly why butterfly numbers were so low this year. I am sure it is a combination of factors. There has been much in the news recently about herbicides and loss of habitat impacting on insect populations. I am sure this is true, but I can't see that would explain this year's sudden reduction in butterfly numbers. Last year was really dry throughout spring and summer and I am sure this must have resulted in a reduction of food plants for caterpillars. I noticed how the wild flowers I had planted struggled. Then from September last year more or less until September this year we had so much rain. A damp winter and then limited sunshine later in the year must have had an impact.

It will be really interesting to see what next year brings. I really hope that butterfly numbers bounce back