Dukes on the Edge

Like most butterfly and moth species the Duke of Burgundy can be quite common at certain sites in Hampshire and extremely rare at others. This is all dependant on weather and how the sites are managed for this species. Many of the sites in Hampshire face North or North East, and are on private land. This is a female Duke of Burgundy taken at Oxenbourne Down in 2020 at rest on grass. Notice the heavily marked wings which is a typical way of differentiating between the sexes, a keen eye will also see the female has six fully formed legs, where the male has only four. Also this female has a very fat abdomen which is full of eggs, hence the need for the six legs for support. This was a fresh one which probably has not mated yet.

Look for the mating behaviour of these butterflies, there is no standing on ceremony when a female comes into a male's territory he strikes very quickly , the female normally flies onto a flat leaf of a Bramble or or other plant close-by and they hook up quickly. They will mate for a few hours, and then the female and male will disengage, and the female will hanker down into a area of tall grasses well out of the way of prying eyes to take some rest. 

This a typical posture of a female Duke of Burgundy as she bends her abdomen around underneath the Primrose leaf. Here it is obvious that the six legs help to support her in this task and most of all for balance in this process which is quite time consuming and takes a lot of effort.

The Dukes on the edge project certainly saved the Duke of Burgundy at the eleventh hour at many sites, in many of its range in Wiltshire, Hampshire, Sussex, and Kent to name a few. A lot of sites were identified for major scrub clearance as many of the sites had nil or very little major conservation work which made the Duke of Burgundy practically extinct in some counties, one being Sussex where it was down to six individuals until this major conservation work started. 

There are a lot of areas in and around Butser Hill which are suitable for the Duke of Burgundy to 'expand' its range naturally, or with some help. This is an area opposite Ramsdean Down which was clear felled and now has scrubbed over naturally

Three Duke of Burgundy eggs laid on the underneath of a Primrose leaf in a woodland glade. They look like pearls in appearance, and sometimes the female will lay one egg on a leaf or several or a clutch of  a dozen or more.

West Wood close to Winchester is managed by the Forestry Commission, and this part of the wood was clear felled several years ago, and then re-planted with more 'natural' trees. The scrubby areas in between the lines of re-planted trees have good clumps of Primroses and have attracted the Duke of Burgundy into the area. Quite where it came from is unclear, but Stockbridge down or an unknown colony close by could be the answer.

This is a SSSI just outside of the Butser Hill NNR and has a small population of Duke of Burgundies

West Butser Hill is a over-spill from the main colony on Butser Hill, when the species has a good year. Females will tend to wander off and start to look for suitable egg-laying sites in a different area if it is suitable. Here it is quite scrubby in places and I have seen upwards of 30 odd individuals here in good seasons.

One of the biggest woodland colonies in the UK is on Porton Down, part of the MOD ranges and being an SSSI, it is known as Isle of Wight Hill which has survived in an area untouched by spraying or any other interference by mankind for many decades. The Duke can reach three figures on this site in good years, with carpets of Primroses never to be seen anywhere else I've been to.

Small isolated sites are very vulnerable and have to be well maintained to keep the Duke of Burgundy from becoming extinct. Here at this site close to West Meon the Duke of Burgundy has a very precarious existence but nevertheless, still survives in small pockets of scrubby downland interspersed with Beech woodland.

Oxenbourne Down 

The main arena on Oxenbourne Down. I've been visiting this site now for over thirty years and it has changed where Gorse has now become quite a problem, and much of the cowslip area has been swallow up by this. This area particularly has remained somewhat unchanged, but I fear it is shrinking but I do see the Duke now here where there is more areas for the cowslips to potentially spread.

For the first time in 2020 I noted an area of clear felled woodland on top of the downland where Cowslips have started to re-generate, and here I found several Cowslips eaten by the Duke of Burgundy caterpillars. The Cowslips are growing on top of a large area of mosses, so hopefully will not dry out in long hot summers.

Female Duke of Burgundy preparing to egg-lay on the cowslips shown above. She is a heavily patterned female a variant known as 'gracilans' which is not uncommon, at certain sites for this species.

Two caterpillars feeding on a cowslip leaf, just to the left of the darker of the two caterpillars is the head of the shed skin of one of them, going from instar to instar, it's now believed that the caterpillars eat their own shed skin.

Oxenbourne Down, Clanfield is a 84.8-hectare (210-acre) Local Nature Reserve north of Clanfield in Hampshire. It is owned and managed by Hampshire County Council. It is part of Butser Hill, which is a Special Area of Conservation and Site of Special Scientific Interest.

This is part of Queen Elizabeth Country Park. It has unimproved grassland on low fertility soils, which is controlled by grazing. There are also areas of ancient semi-natural woodland.

 Co-ordinators Notes on Oxenbourne Down 2020

April 2020 was the warmest April month ever recorded, and the 5th driest on record but unfortunaetly due to the Lock Down and very little recording going on, the Duke of Burgundy emerged probably just as early as 2019, but we shall never know. However Oxenbourne Down presented some very interesting notes in 2020.

 

As ever the Gorse is still a potential problem at the top of the downland, but it would seem the Duke of Burgundy is utilizing a break for freedom, now being recorded away from this core area, which by 27 April I hadnt recorded in the Gorse area, but the area shown in the photograph (top right) there would seem to be more activity here, especially females, and also males on territory in good scrubby areas facing South-East, which is something I hadn’t noted over many years why there hasn’t been more activity in this area. 

 

This is the area of clear felled downland which was covered in tall pine plantations in the latter part of the 20th Century, and now the Cowslips have started to germinate, and good clumps are now well established, and in 2020 was my first ever recording of female’s laying eggs on the leaves of the Cowslips.

This is the Gorse covered area, which has to be cut back quite significantly to promote the growth of cowslip 

April 27th 2020

 

The Males had occupied several of the scalloped areas in the Gorse strewn habitat at the far North-Western end of the down, and a female was seen looking and searching for suitable Cowslips, clumps in which (I assume) to lay her eggs. She was searching around a clump of leaves but was not interested in laying eggs, she then flew off, and started to imbibe on some Wild Strawberry flowers, of which this is the second time I’ve witnessed this.

 

Is this a precursor to laying eggs, or after?

 

A visit to the area where there is a substantial clump of Cowslips on the top of the down, at 12:00 produced no females or males in the area. In fact they were not seen in any great number at all along the scrubby area between this site and the Gorse area, except several males on territory which looked quite worn.

 

As we all know they can be very hard to detect if they are only on site in one’s and two’s, but this site probably harbours better numbers than I have managed to count over the years.

 

May 4th 2020

 

The Males had occupied several of the scalloped areas in the Gorse strewn habitat at the far North-Western end of the down, and a female was seen looking and searching for suitable Cowslips, clumps in which (I assume) to lay her eggs. She was searching around a clump of leaves but was not interested in laying eggs, she then flew off, and started to imbibe on some Wild Strawberry flowers, of which this is the second time I’ve witnessed this. Is this a pre-curser to laying eggs, or after?

 

A visit to the area where there is a substantial clump of Cowslips on the top of the down, at 12:00 produced no females or males in the area. In fact they were not seen in any great number at all along the scrubby area between this site and the Gorse area, except several males on territory which looked quite worn.

 

As we all know they can be very hard to detect if they are only on site in one’s and two’s, but this site probably harbours better numbers than I have managed to count over the years.

An area on top of Oxenbourne Down where there has clearly been some contractual work to keep the gorse back and to create large scallops, which the males like to have as a territory, and entice a female when passing into mating with him.

Looking for the tell tale signs of caterpillars feeding on the cowslip leaf is a time consuming job but well worth the effort to establish how the species is faring at certain sites

A female Duke of Burgundy starting to lay her eggs on the edges of Cowslip leaves, using her 6 legs for balance. This is the same specimen known as 'gracilans' shown in the other picture.

7th June 2020

 

Another visit to this site at the same spot where I had seen the females laying eggs on the 4th May and there were several areas where I could distinctly see that there was leaf damage by the caterpillars feeding on the Cowslip leaves. I looked and found two caterpillars on one leaf at the bottom of a Cowslip plant. These were into their second instar, and I noted there were the remains of a 1st Instar skin close-by. They were not feeding at the time, as it was probably not warm enough.

 

I looked at several other areas and also found leaf damage, but no caterpillars, but it does suggest that the clear felled area is now a good area for breeding. Also the Cowslips are situated amongst good areas of moss which was wet which could help aid and stop the Cowslips drying out, in drought conditions.

Scrub bashed area on a site east facing chalk downland in the Meon Valley, this is a an area covered in hazel and buckthorn bushes and would become quite impenetrable is not cut every three or four years. This encourages the rigorous growth of Cowslip. 

In some good years certain sites have a partial 2nd generation, these are quite rare but with global warming it could become commonplace. This is a male taken in August at Noar Hill where there has been several 2nd generations in the last several decades. In one year I saw the Duke of Burgundy in April, May, June, July and August.

A freshly emerged male Duke of Burgundy. This male was just resting on a dried grass stem after drying its wings, soon it will take up a territory and will mate with a female in its very short life span of 8-12 days.

The same site from a different angle, looking south, here you can quite clearly see the encroachment of buckthorn bushes and other bushes like hawthorn and hazel.

Here you can see the rigorous cowslip growth after a couple of years

 Tytherley Woods Project 

Project and brief description: Tytherley Woods Project. The South East Woodlands Project carried out by Butterfly Conservation was a five-year project to enhance woodlands for butterflies. Tytherley Woods, a large group of woods to the east of Salisbury and centred on Bentley Wood, was one area in this project where land owners, managers and conservation volunteers were involved in various tasks such as educating, monitoring, management, workshops, public events and generally raising the awareness of the importance of these woodlands for some of our rarest butterflies. Forestry Commission was involved in providing Woodland Improvement Grants to implement management for fritillary butterflies in Tytherley Woods Location of project and which BAP areas this includes: Tytherley Woods in Area 11.

 

Timescale of project: The project had a full-time officer and finished in 2011. Wiltshire branch is trying to maintain the momentum created by this project. We have a close relationship with David Lambert, Bentley Wood manager who coordinates the monitoring on six butterfly transects in the wood. Aims/Objectives of the project: To enhance woodlands for butterfly species through practical conservation tasks and application of Forestry Commission Woodland Improvement Grants. Target species/habitats of the project: A wide range of butterfly and moth species, particularly fritillary species, including Marsh Fritillary, Pearl-bordered fritillary, Small pearl-bordered fritillary, Duke of Burgundy, and the Argent and Sable Moth.

Woodlands like Bentley Wood on the Hampshire and Wiltshire border have benefitted from projects like the Tytherley Woods project, which helped species like the Duke of Burgundy and other species on the brink. This is the Eastern Clearing the small part of this woodland which is in Hampshire. Here the large areas of damp meadows have good numbers of Pearl-bordered Fritillaries and to a lesser degree the Small pearl-bordered Fritillary, which is in serious decline here, and could could quite easily become extinct here in the next few years..