Costa Rica Butterflies November 2024 - Part 1

Where to start with our trip to Costa Rica last November? It wasn't exactly the holiday of a lifetime that we expected, but it was a fantastic experience nonetheless.

Maybe we should have realised when the pilot informed us that our flight would be landing a little later than expected because we would have to fly around Tropical Cyclone Sara. I never imagined that the deep depression over the Gulf of Mexico, which slowly moved west and north, would have such an impact on the weather in western Costa Rica. We didn't get much wind at all, but what we did get was rain! Lots of rain! The first few mornings were cloudy with occasional sunny spells turning to rain by about 11am which would continue for much of the day.

We visited Nicaragua on the fourth day of our holiday where the weather was reasonably dry, but on our drive back our guide informed us that it had rained all day in Costa Rica and that the road back to our hotel was flooded. Luckily the water had reduced enough by the time we passed to allow us to get back safely.

For the next three days the rain just didn't stop. We were told that in that time as much rain had fallen as would normally fall in a whole year in that area. There were mud slides and flooding causing great damage to the roads and airport. The weather slowly improved after that, but there wasn't a day without some rain and it was only on the last day of our two-week holiday that we had a sunny morning with cloudless skies!

I say two-week holiday, but the rain caused damage to the runway at the airport, so many flights in and out were cancelled. Luckily the airport opened the day after our flight was due, so we were only delayed by one day.

We were staying right up in the north west of Costa Rica, very close to the Nicaraguan border. This is a coastal area of "dry forest" - mostly deciduous trees. We were there right at the end of the rainy season and should have expected a heavy shower maybe every second afternoon.

Unfortunately, the weather also meant that the national parks were all closed, so we didn't have an opportunity to venture into the cloud forest or any other parts of Costa Rica. Therefore, butterfly viewings were restricted to what I saw in the mornings at the resort, or along a track opposite the entrance to the hotel.

However, the few sunny spells we had really showed the potential for butterflies. I was amazed that after a day or two of non-stop rain, as soon as the sun came out butterflies would take to the air. They must be expert at finding good sheltered spots. I also noticed that about ten minutes before the rain started all the butterflies would disappear, so they seemed to know when the rain was about to come.

In the mornings, when it wasn't raining there were almost always butterflies in view. The hotel had enormous grounds with meandering swimming pools surrounded by tropical gardens. It was mostly various shades of yellow, or white butterflies that were flying around there interspersed with all sorts of other shapes, colours and sizes. By the afternoon there were fewer butterflies around.

There was also an amazing variety of other wildlife that frequented the hotel grounds and surrounding forest. The air was always full of bird song and other strange noises, including the roar of Howler Monkeys. White-faced Capuchin Monkeys paid regular visits to the hotel and its grounds and I saw Spider Monkeys just outside the hotel. There were several other mammals and also various Iguanas, Lizards and Skinks all around.

Despite the weather and limited search area, I still managed to identify 68 different species of butterflies and I saw many more fly past that were impossible to identify. Given that over 1,800 species of butterflies have been recorded in Costa Rica along with over 12,000 moths, it is understandable that butterflies need to be clearly photographed in order to identify them. Further complication is added by the enormous number of mimic species of both butterflies and moths and that a number of species have wet and dry season forms and males and females that look completely different!

On that final sunny morning I couldn't believe the number of butterflies flying everywhere and I saw several species that I hadn't seen in the previous two weeks. And on the drive to the airport there were all sorts of amazing butterflies flying along the edges of the roads. I can hardly imagine how many more species I would have been able to see had the weather been better and we could have travelled to different areas of the country.

Over the next few posts I will show the butterflies I managed to photograph.

East Lothian Butterflies 2024 - Part 2

Continued from my previous post.

The number of Small Skippers recorded took a dip after they have been increasing since they were first recorded in East Lothian in 2011.

Large Skippers are now found all across East Lothian, but we only receive a few records. I think it is quite a difficult butterfly to spot and identify as it zips about between flowers.

Ringlet numbers were a little lower than average, but nothing significant. 

However, Meadow Brown numbers were down to about 75% of the average.

Holly Blue numbers crashed. After the odd sighting for many years their numbers have increased since 2019. They started off very well in the spring of 2024, but the summer generation was very much lower than expected. Across England the annual population fluctuates in response to a parasitic wasp. This wasp was discovered in 2024 by a local enthusiast who had reared some Holly Blues, only for some to fail with wasps appearing from the chrysalises.

There are a number of small, isolated colonies of Northern Brown Argus across East Lothian. They are found north of Traprain, east of Dunbar and in the Lammermuirs. Some of the known colonies may have died out and there are likely more undiscovered locations. Because of their remote locations we struggle to monitor how they are doing. In 20224 the Countryside Rangers received funding to plant Rockrose at a coastal site and they worked with Bear Scotland to plant up a south-facing road verge. Once these are established they will hopefully these will provide stepping stones between the existing colonies. 

Grayling butterflies continue to be found at three semi-urban sites. Sadly two of these locations are being developed, so I suspect we may lose those colonies. The exciting new was that there was a Grayling photographed on North Berwick Law last summer and they were also seen in the Lammermuirs.

The Small Pearl-bordered Fritillary is a rare butterfly in East Lothian, but they are found in a couple of locations in the Lammermuir Hills. They were seen in one of the Lammermuir valleys last summer.

And finally, hairstreaks! We have long been aware of a few small colonies of Green Hairstreaks around East Lothian. They are mostly in quite remote locations in the Lammermuirs, so I don't often receive records of them. There was a colony in Saltoun Big Wood, but there have been no Green Hairstreaks recorded there in the last few years, since there was a fire in the small area of woodland where they were found.

Having found adult Purple Hairstreaks in 2022 at Woodhall and Dunglass, two enthusiasts returned to East Lothian to search for eggs last winter. They did a very thorough job collecting carrier bags full of terminal buds from fallen Oak twigs and branches and searching them with a magnifying glass to look for eggs. Amazingly they were successful in finding eggs in six woodland across East Lothian. The adult butterfly rarely leave the top of mature Oak trees, where they can be seen flying in the late afternoon and early evening. Despite a lot of effort searching these woods in the past Purple Hairstreaks haven't previously been recorded in these locations.

Probably the most exciting news of 2024 was the sighting of a White-letter Hairstreak in a garden in Haddington. This is the first sighting of this species in East Lothian. They have made their way out of Northumberland and into the Scottish Borders over the last few years, mostly along the Tweed Valley. So, this is a big jump for the species. However, one was also recorded in Edinburgh and another in Dundee. It is fascinating to consider how these butterflies have spread so far, or if they have been there for a while. It will be interesting to see how they do over the next few years.

It certainly wasn't a great year for butterflies, but I think East Lothian probably did better than the UK as a whole, with one or two species actually appearing in good numbers. Some of the species such as Meadow Brown, Comma and Red Admiral did amazingly well in 2023, so the lower numbers in 2024 are almost to be expected.

Certainly I noticed that numbers where I live in the Borders were pretty similar to East Lothian. Given the wet summer that we had it isn't really surprising that numbers were a bit down. The next few years will give a better idea of how things are going. Let's hope for some decent weather!!

As always, thank you very much to everyone who took part in a transect or who sent in records. I am always delighted to receive them.

East Lothian Butterflies 2024 - Part 1

There has been a lot in the national press about how badly butterflies have done in 2024. Certainly the weather wasn't ideal for them, but looking through the records I have received, I am surprised that things in East Lothian weren't as bad as I was expecting. Some species did well while others were seen in very low numbers. It is difficult to know why this should be.

The year started off with quite a mild, but stormy winter. Much of the spring and summer was cooler, with a lot more cloud and showers than normal. Of course, there were a few sunny days, but the weather really didn't improve until September, which was a little late for the butterflies!!

There is no perfect way of recording butterflies. Transects are great for comparing year on year for the same location, but in East Lothian they are mostly coastal, with two along the River Tyne. The ad hoc records are from all over the county and can pick up all sorts of interesting records. However, there is a lot of luck involved with being in the right place at the right time. They can also result in big spikes because a lot of enthusiasts, including myself, may be out on the same sunny day looking for butterflies!

Poor weather not only means that butterflies may not be flying, but also enthusiasts may not be out looking for them! However, it is amazing how quickly butterflies will appear when the sun does come out but they may go unnoticed if recorders aren’t out and about!

The records I have gathered are from ten transects that are currently walked in East Lothian along with ad hoc records from the East Lothian Countryside Rangers and about 20 volunteers. This gives a pretty good indication of butterfly numbers and can be compared with the previous 11 years when about the same number of people have been submitting records.

The first butterfly record I received from East Lothian was a Peacock on 16th February. This was quite early, possibly reflecting the mild winter. Peacocks did quite well in East Lothian with high numbers been seen later in the year.

In contrast the Small Tortoiseshell had a very poor year. Their numbers have been declining in recent years, with 2024 returning half the average number in East Lothian and it was the worst year for them since I started these comparisons in 2013. This is a worrying trend that has been seen across the UK.

The Red Admiral also had a very poor year. We had a few early records, which may have been butterflies that had survived the winter here. The arrival of migrants was a couple of weeks later than normal and then we had lower numbers later in the year when normally we would expect to see the next generation.

The figures for Commas in 2024 would suggest it was a fairly average year for them. However, a good proportion of the records were from three counts of over 20 Commas that were recorded in one particular woodland in September.

2024 was the worst year since I started collating the records for Painted Ladies. I only received 14 records of them and I haven't seen one in the UK for the last two years. The numbers that make it to our shores depend on how their relatives have done earlier in the year on their multi-generational journey from Northern Africa. In good years, such as 2019 their numbers can be spectacular.

Orange Tips had a very good year. They appeared a little later than normal, but were seen in good numbers.

Interestingly the spring population of the Green-veined White and Large White were lower than normal, but their numbers picked up for the summer generation. So, both species ended up being recorded in fairly normal numbers.

Small White numbers can vary enormously from year to year. 2024 numbers ended up being just a little less than average.

One of our more recent arrivals (2009), the Speckled Wood, had a fairly normal year.

The Wall Brown, which arrived about the same time, peaked in numbers in 2021, but has since been declining. 2024 saw about a quarter of the number recorded in 2021. There has been a dramatic reduction in numbers of this species in England and although it appeared to be moving north in response to climate change it will be interesting to see what happens to the East Lothian population in the coming years.

The Small Copper had a very poor year, with the lowest number since I started collating butterfly records. 2024 saw about a third of the average number.

Two species that appeared to have a very good year were Common Blues and Dark Green Fritillaries. They both tend to live in similar habitats and fly in June till August.

However, another species that inhabits similar landscapes is the Small Heath. Sadly they had a poor year, which is a little difficult to understand.

I will continue this on the next post.

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