Holly Blues in East Lothian, Celastrina argiolus

This beautiful little butterfly is found extensively across England and Wales but there is only the odd record in Scotland. Most of those are from East Lothian, although they have been recorded in Fife and the Scottish Borders.

I was always aware of a colony on the western edge of East Lothian, but when I checked out Butterfly Conservation’s records for the area, I only found one record from 2013, although I know they had been seen there for many years before that. It just shows the importance of making sure that sightings of any butterflies are sent to the local recorder. Sadly, following a series of cold winters that colony appeared to die out.

For the last ten years, though, there have been single sightings each year from an area around three villages in the north of East Lothian. These have all been from Dirleton, North Berwick and Gullane and I suspect that there is a large private garden somewhere in that area containing Holly and Ivy where a colony of Holly Blues has secretly been living. Those individuals that were seen could all have flown from that one colony.

Despite the efforts of a few of us, we have never found where that colony may have been.

In 2011 there was great excitement, as three Holly Blues were seen on the outskirts of Aberlady. However, despite careful checking of the area since, they were not seen there again.

Then in 2019 some Holly Blues were seen feeding on Snowberry flowers on the outskirts of Gullane, right next to a popular path. I am sure that they would have been spotted in previous years if they had been there. I think the maximum count seen then was 7 butterflies.

A little later in the year a second colony was found a few hundred yards away and a couple of individuals were spotted on the outskirts of the village.

In 2020 we anticipated their return, but we were disappointed that no one saw any in these two locations during the spring. We wondered if these were yet more failed colonies that couldn’t cope with our winter weather. However, I started to receive records from other areas of East Lothian, up to 12 kilometres away. I think we had records of 38 Holly Blues that spring and later in the summer, when the second generation was flying, we had a further 52 records come in, including several from the two colonies in Gullane and from the site in Aberlady where they were seen in 2011.

I would love to find out more about Holly Blues. I get the impression that females must fly from the original colony for up to about 10 kilometres in search of somewhere to lay eggs. This would explain the individual sightings over the last few years and the new colonies that have sprung up around East Lothian. Many of these are in areas that have been regularly surveyed by enthusiasts, so any Holly Blues would have been spotted there in previous years.

Already this spring there have been quite a few records sent in from the areas we found them last year. It will be interesting to see if they expand their range further when the next generation appears in August.

I guess I will never know where the original colony was, but it is great that Holly Blues are now becoming a regular site in East Lothian.