Quick update from Collard Hill – 24th June

May I first thank everyone who visits Collard Hill, Its fantastic to see and hear your stories from around the country – several of you have been to oxford and seen the Black hairstreaks the past few days.

Numbers of Large Blues are steady with about 6 being seen today – two were laying females this morning which is great news!

It was pretty hot on the hill today, the truck themometer was readiong 24 and that was in the shade…

This meant that the majority of Blues that were seen were sticking to the gorse areas down the gentle track, its a little cooler for them down here.

We were joined by three full time volunteers today from the Holnicote Estate today. Not having much limestone grassland where they work, it was a great chance for them too see a different site, learn about the project and see plenty of limestone grassland species – they certainly tested my knowledge today!

The weather for tomorrow is looking a little cooler with some rain coming mid afternoon and just another piece of information –  glastonbury festival is starting on Thursday so I can imagine there may be quite a bit of traffic on the roads tomorrow – you are still welcome to visit though!

Thank you to all who have been sending in photos of their visit to Collard, we hope to get them uploaded over the next couple of days.

Hayley – Ranger for the Mendip and Polden Hills

Marbled White - Hayley Dorrington

Marbled White – Hayley Dorrington

Large Blue Report – 22nd June – A Very Successful Open Day

Just a quick one today as I don’t have much time to do a proper post with bells, whistles and pictures :(

Today’s open day went really well, with over 100 visitors chancing their luck at seeing Collard’s star of the show. I am willing to say, with confidence, that almost everybody who came today managed to catch at least a glimpse of a Large Blue.

The general success rate of the day was largely down to this one highly immobile female, who really drew in the big crowds.
Sightings stayed around the same amount as usual today, around 10-12. Once again the vast majority of sightings were individuals who weren’t on the wing, a few laying females and very few males.

It’s still very much too early to tell which way the numbers are going, but my gut instincts tell me we might just see them rise yet, but don’t hold me to that!

Tuesday I’ll have time for a nice proper review of the trends over the next few days with pictures I’ve taken myself as well as those of all the kind folks have sent in :D

Stay tuned!
Thanks for reading!

Jono, The Large Blue Ranger.

Large Blue Report – 21st June

Collard’s run of perfect weather continued today with temperatures well into the 20’s and barely a cloud in sight.

General numbers across the site of all butterflies seemed to fare much better than yesterday. On our first transect, 50 Meadow Browns and over 20 Marbled Whites were counted. Across the site there are at least 17 species to see at the moment.
This trend was also (just about) seen in Large Blues, with around 8 visitor sightings. The majority of these were once again females laying on the slopes of the eastern glade. I spotted a female myself on the other side of the hedge at the top of the eastern glade, this area can be a nice little unexpected spot to see them.


The extremely hot weather meant that very few of these sightings were on the wing, and were mainly made by disturbing individuals or spotting them while resting.
If the majority of LBs on the site are inactive, this is a potentially positive sign in terms of population numbers. It may be that many individuals have just been extremely difficult to spot on many days. Inactivity unfortunately means that the chance for visitors to spot them is fairly low.

Vegetation quiz time!
Anyone who can ID this one gets a big pat on the back, it had myself and a few of our visitors scratching their heads today.


But anyway, back on topic. Second guessing the direction in which the populations are heading in the near future is a really difficult task, we’re still not sure whether or not populations could increase soon. We’ll just have to wait and see. Part of the beauty of butterflies is their ability to vary so much from year to year, ripping up the rulebook with reckless abandon.

Thanks for reading!
Stay tuned for more updates!

Jono, The Large Blue Ranger

Large Blue Report – 20th June

Hello all!

Today was once again fantastic weather for butterflies, unfortunately today they didn’t really fancy coming out to play.

Matthew Oates joined us up at Collard today, to give his expert opinion on how things are looking. Amazingly we didn’t see a single Large Blue today. Visitors reported only 4 individual sightings, 3 of which were on the upper slopes of the site.

It’s still very early to draw broad conclusions about the season, but essentially there’s some good news and some bad news.

The bad news:

  • There’s enough thyme out on the site now that we would expect the numbers of blue to be significantly higher. It’s not a good sign that we’re at least 5 days in with such poor numbers.
  • In all previous years, the populations would have exploded by now given the conditions across the site. It now seems unlikely that we’ll have a big explosion in their populations.
  • General butterfly populations seem fairly low across the site in comparison with previous years. This is a fairly good indicator that conditions on the site are generally poor (as a result of weather strangeness).

The good news:

  • There’s a big difference in thyme emergence across different areas of the site. Staggered stages are ideal for LBs as it means later individuals will still have a nectar source and place to lay.
  • There may be more individuals than we have yet realised, however their behavior may have made them hard to spot. For example, LBs may require that adult populations reach a certain density before they become truly active, a rule that holds true for many other species.
  • These conditions aren’t specific to Collard, other LB sites’ vegetation seems to be at roughly the same stage.
  • There may still be time for numbers to improve, however unlikely it seems.
  • Collard Hill is still a lovely place to visit!

So, there is still a little time for things to pick up at Collard but I really really have to emphasize that the likelihood of visitors seeing Large Blues at the present time seems to be fairly poor. There is absolutely no guarantee.
If you’re planning a trip specifically just to see the Large Blue, I’d hold off to see if things pick up. If you think you’ll enjoy everything else the site has to offer then I’d encourage you to come along!
Once again, this is still early days, and trying to predict the behavior of these little beasties is a very very imprecise science.

Speaking of all the other things the site has to offer, today we found a couple of mothy treasures.

The caterpillar of the now rare Small Eggar Moth:


And caterpillars of a moth species whose name completely escapes me. Matthew mentioned it but even he wasn’t 100% on it, so 10/10 for anyone who identifies these in the comments!



Thanks for reading everyone! Obviously I’m keeping the blog updated daily so remember to keep checking back for updates – if population levels drastically increase the blog will be updated as a matter of urgency!

Jono, The Large Blue Ranger


Large Blue Report – 19th June

Absolutely SCORCHING day up on the hill today – I don’t think I saw a single cloud in the sky until 5 o’clock. This weather made for a fairly unusual day at Collard. We had a generally active morning with everything going quiet from about 12 o’clock until gone 3 o’clock. Everything needed a good rest today.

We had a few sightings of LBs today, mainly in the upper slopes of the eastern glade (for females) and above the quarry (for males). Visitor sightings numbered at around 8-10.
The really interesting find came at around 1 o’clock. A visitor found a female laying eggs but it was behaving very strangely; extremely immobile, reluctant to fly, and accepting of people getting relatively close to it. This female stayed around the same area of the site from 1 o’clock onwards. Luckily this meant very very few visitors came to the site today who didn’t get to see a Large Blue!

Although her behavior seemed odd, (occasionally she would fall from flowers and take a long time to get comfortable) it is fairly normal for butterflies to react to exhaustion this way. Exhaustion is brought on by extremely hot weather with little cloud cover, in combination with the exertion of mating and laying eggs – extremely energy intensive activities.
It is however, very rare to find a butterfly in this condition, as when they are resting on grass stalks they are fairly well camouflaged.

This was probably the most obliging subject anyone will have at Collard for the foreseeable future (she still never opened her wings though!).


This beautiful obliging subject nectared on this Pyramidal orchid for in excess of 20 minutes.

In other news;

Good numbers of Marbled Whites are starting to emerge and they’re still really fresh and crisp – a beautiful sight. Photographing these is hilariously difficult.


I’ve spotted a few newly flowering vegetation species out on the site recently!



Restharrow – will soon be easily spotted along the lower slopes of the site where it’s quite abundant




Field Scabious – A wonderful flower with a really eye-catching ethereal colour to it.

The Lesser & Common Century are also really starting to come into their own – Lesser grows in much shorter denser patches, and is just a really nice little pink flower.

Thanks for reading everybody!

Jono – The Large Blue Ranger

Large Blue Report – 18th June


Today turned out to actually be a pretty great day for searching out Large Blues. The weather was a nice mix of cloudy/sunny spells. Any photographers out there probably already know that a bit of cloud is essential for good butterfly weather if you want to do anything other than see them whizz past you at a distance. Under cloud, you can follow them until they roost, at which point you can snap away to your heart’s content or just get a bit of time to really study them in detail.

I was joined on-site today by the extremely knowledgeable and experienced butterfly enthusiast Niel Hulme (link to his excellent UK Butterflies diary). We spent a lot of the day together searching out the best spots on the site to find Large Blues.

Although difficult to estimate the precise numbers of individual Large Blues present at the sight right now, we couldn’t find proof that there are any more than two individuals. Our first sighting was of a male, in the sheltered area above the main track, at around 10 o’clock.
I later saw a male at the very top of the track, set down on the ground to roost as a cloud came over, allowing me to line up my first proper shot of the season! It’s far from spectacular, but catching these guys with their wings open is nigh on impossible.


Neil and I compared photographs and decided that this was the same individual as the original sighting. I later sighted an LB flying out of the South entrance to the quarry – unfortunately it moved too quickly for me to get a proper look at it and it was straight over the scrub.

Much much later in the day Niel spotted a female, on a very different part of the site, laying her eggs on budding thyme. This is a really encouraging sign that things are moving in the right direction and that numbers should start to increase soon.

For the rest of the day there were few sightings until after the butterflies had had their usual siesta (they rest from around 1 – 3 if they’ve been active). We then saw what may well be the same male from before racing around the Eastern Glade at breakneck speed. Trying to keep up with it was both extremely good fun and extremely tiring.

It’s still early days here at Collard, but we’re starting to get a hold on their preferred flight areas so if there’s good weather and you’re in town there’s a pretty good chance you might just catch one while they’re still in their fresh pristine condition!

Thanks for reading!
Jono, The Large Blue Ranger

Large Blue Prospects (morning report) – 18th June

Large Blue Collard Hill

Photo by David Simcox

Good morning all!
First I’d just like to quickly apologise for the lack of recent updates to the blog, I unfortunately had to leave the county Sunday and have only just returned.

The good news is that sightings of the Large Blue have continued at Collard, although still in generally low numbers.We’re already receiving plenty of great pictures from visitors.

Taken by Thalia Brown

Currently the best place to see them seems to be along the slopes above the quarry (pines) or below the gorse adjacent to the main tractor track which runs down the hill. (If you find me in person I’ll be able to show you exactly where I mean!).

Taken by Rrobert Godden

Today’s weather is looking fairly poor for butterflying, cloudy until very late in the day (6 o’clock onwards) when the sun might begin to poke through the clouds. Temperatures are forecast for 20°+ from around 1 o’clock onwards. It’s likely few individuals will be on the wing today, but the eagle eyed amongst you might be able to spot them resting.

David Habbershaw

Taken by David Habbershaw – one of the first sightings of the year!

But yes, it is certainly looking like flight season is now underway, although it will be a little while until the site really hits its peak.

Thanks for reading!
Jono, The Large Blue Ranger

First sighting today!

The day we’ve all been waiting for is finally here! Had our first unconfirmed visitor sightings today at around 2:30. It seems they may have emerged on exactly the same day as last year!

It’s very likely that these individuals are early and it’s probably going to be a little while before the population really starts to get going as the thyme across the site is still mostly in its very early stages.

A word of warning; plenty of visitors today went home without seeing any LB’s at all, and these few sightings are by no means a guarantee that visitors in the near future will be certain (or even likely) to see this amazing butterfly.

This is excellent news though and a really good sign that more are likely to follow.

From Collard Hill, Jono, The Large Blue Ranger.


So just where are these Large Blues? – 13th June Large Blue Report

Still no Large Blues on Collard. Today was another perfect day of flight weather – clear blue skies and very slight breezes.

So why aren’t they here yet?
It’s a bit of a mystery. Since their introduction, their flight period would traditionally begin around mid-June. Over the years, this flight period has become earlier and earlier. 2012 saw Large Blues beginning to emerge as early as the 1st of June.
This adjusted flight time is very much what everyone has been accustomed to.

Last year was a bit of an upset to this pattern. The Blues didn’t first emerge until the 14th of June, this was predominantly down to a run of seriously negligible weather; extreme wet followed by drought conditions meant the majority of the thyme across the site was in a real bad way, and the general trend of increasing LB numbers was reversed, falling to equal the totals of 2010.

This year’s weather has been comparably perfect. We’ve had a mild winter which has brought out many of our flowers and insects out earlier than we’re used to. We’ve also had clear skies and ideal flight weather since the 6th of June, plenty of time for them to emerge.

The interesting thing about the delay in their emergence on Collard is that it seems to be intrinsically linked to the flowering of the thyme.The thyme across the site is clearly still in its early stages, as anyone who’s visited the site will have seen for themselves. It is clearly a good thing that the LBs didn’t emerge before their larval food-plant is at its appropriate stage.

Strictly speaking we’re not sure exactly of the mechanism which means the phenology of the LB and thyme are so tied together, but it’s extremely unlikely that the pupa of the LB can ‘tell’ (for example from scent) that the thyme is in flower. It seems more likely that the thyme flowering and pupa emerging are driven by the same external factors.
Specifically, I’d speculate that a possible external factor is ground temperature.
If ground temperature is a key factor in thyme flowering and LB emergence, it might make sense that everything is a bit behind at Collard. England saw record amounts of rainfall in January, and throughout the year Collard has seen its fair share of rainfall. It’s possible that the clay-heavy soils of Collard have retained a huge amount of this water, keeping the ground temperature lower than comparable sites.

It’s also very possible that we may be seeing some kind of knock-on from last year’s bad year. With the LBs complex life cycle it is tricky to pinpoint exact impacts.

This is mostly speculation, and we won’t have a full picture of what might be going on at Collard until after they’re out, we’ve monitored their numbers and fully assessed climatic effects. Until then this is pretty much my line of thinking though!

Today’s report turned out to be more of an essay, I’ll try to get back to form tomorrow!

Thanks for reading! We’d be glad to hear anyone else’s thoughts on the matter in the comments.

Jono, The Large Blue Ranger


Large Blue Report & Picture Submissions! – 12th June

Still no Large Blues!


Today once again looked like it might be the day, a gorgeously misty and dewy morning gave way to the sunniest day I’ve seen yet at Collard, there was barely a cloud in the sky and hardly any wind at all.


Perfect flight weather brought out all number of invertebrates in addition to our wealth of butterflies. In particular, Mayflies were out in huge numbers today. A mating pair flew into my face at one point which was uhh… an experience.


Butterfly species seen today included: Red Admiral, Small Tortoiseshell, Speckled Wood, Small Heath, Meadow Brown, Marbled White, Painted Lady, Clouded Yellow, Common Blue and Large White. Unfortunately I’ve not seen the Small Copper since it’s first appearance, which makes me sad as it’s one of the most striking species of butterfly I’ve had the pleasure of seeing.


Today’s other points of interest:
I spotted some cool fungi growing on our spectacular Oak near the viewpoint & bench.


Whilst I was resting in the shade of said Oak, I was visited by a pleasant little Chaffinch.


I also spent a hilarious 15 minutes chasing around after the ridiculously mobile Hummingbird Hawk-Moth we’ve got on site:


… It didn’t go too well.


Seriously these things are fast.

This is pretty much the best I could do.

I’m so sorry everyone.


Other than that there’s really very little to report from today, we’re still waiting with baited breath for the first Large Blue to emerge.

Thanks for reading!

Jono, The Large Blue Ranger


Today’s excellent picture submissions are from John Aldridge, you too can get your best pictures featured on the Blog if you submit them to Collard.hill@gmail.com. Unfortunately it seems that wordpress’ library feature seems to ruin the image quality so we’ll try to work on this!

John Aldridge


Chrysoteuchia culmella


John Aldridgemeadowbrown