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Dukes Spreading

Over the last few days I've spent some time looking at some of the smaller Duke of Burgundy colonies in the Arundel area, where natural colonisations are at the stage of (hopefully) becoming firmly established - one of these is at the Fairmile Bottom LNR. Things are looking promising. At one site I had a Duchess land on my rucksack; she must have emerged that morning, as ten minutes later she took to the air and was chased by three males, the fastest of which grabbed his prize.

Albomaculata

I spent a very enjoyable day (12 May) monitoring Duke of Burgundy numbers at Kithurst Hill and on private land in the area, seeing a total of 75 individuals in all. The pick of the bunch was an aberrant female (ab. albomaculata) at Kithurst, where numbers have increased significantly since yesterday. I even found Dukes in the hollows of the chalk grassland restoration area, before entering the meadow (the Cowslips here are better than they've ever been).

Thanks for the update, Neil. With all the excitement regarding the PBFs, the poor Dukes are in danger of being sidelined somewhat.

Encouraging to hear those numbers, and that last female is indeed a striking specimen, although I actually prefer the one on your rucksack; makes a change from your trousers!

Hi David

Fortunately, the Pearl-bordered Fritillary and Duke of Burgundy flight seasons have been eased apart by the cool period of spring weather this year, at least in Sussex. PBF is on the wane at all but one site in the county, with Dukes only having really got going over the last few days. This is a huge relief to me, with so much monitoring to do.

I'm pleased to say that the numbers of both are excellent this year; records (for this century) will undoubtedly be broken. The only Sussex site bucking the trend is Heyshott Escarpment, which is rapidly dropping down the league table for Dukes.

Recent highlights include a lovely dark PBF ab. transversa and numerous mating pairs of Duke of Burgundy.

BWs, Neil

That is a cracking aberrant Neil Any predictions for the start of the Small Pearls over your way (we're a few days behind - that's if there any this year ) ?

Have a goodun

Wurzel

Neil,

The ab. transversa is a stunner, what a find. That is by far my favourite photo of the season so far.

Regards Kev

Hi Neil,
have you any idea why the Dukes are struggling at Heyshott, compared to other Sussex sites?

Thanks, Wurzel and Kev. SPBF started yesterday on the Sussex BC reserves.

Hi Mike. The scrub-cutting regime at Heyshott is currently far too aggressive in my opinion, being annually too extensive and of an insufficiently rotational nature. A very large area of the reserve now lacks Dogwood regeneration in the 1 and 2 year class, which renders the Cowslips too exposed to UV and prone to drought - they are reverting to the undesirable growth-form (small, flat rosettes). This also reduces the suitable habitat for other species, such as Tree Pipit, which has failed to breed on the slope for the first time in many years.

BWs, Neil

Dukes Aplenty

Yesterday (16 May) I covered many (but not all) of the scattered Duke of Burgundy colonies on the Downs near Storrington, some of which are on private land. My final tally of 104 individuals sounds very good, but the cold wind blowing directly onto the escarpment (Dukes hate northerly and easterly winds) undoubtedly kept the numbers down, particularly under increasing cloud cover. However, I saw enough to know that there is much better to come, and that this species is having a very good year in Sussex. Even under these adverse conditions I found half-a-dozen mating pairs.

During a previous visit, on a much warmer day, I had my highest ever count of Dukes at Kithurst Hill, where they are far more widespread than in previous years. My thanks go to all those who are doing their best to keep to the existing pathways across the meadow, as this helps reduce the trampling of foodplants.

As always, I'm struggling to monitor all Sussex Duke sites, so any records from Harting Down, Washington chalk pits and Fairmile Bottom (searches required along the scrub-line at the base of the slope) would be most welcome.

In the evening I visited my local site for Field Cricket, where the air was filled with the exotic sound of their chirruping.

Hi Neil .
What do you reckon the chances of the field Crickets singing and showing their selves ,3rd week in June ??
Great pictures by the way ! Regards Allan.W.

Great news, Neil....and that's a beautiful aberrant PBF in your previous post.

Thanks, both.
Allan: The be honest I never search for Field Crickets that late in the year - I always visit in mid May. Finding them in the open (usually on their 'arena' - the bare patch of ground outside their burrow) takes a great deal of patient searching and stealth. They come out of their burrows to sing (attract mates), clear vegetation to keep the arena clear, and to forage, and the necessity to perform certain tasks may change with the season, once the majority of mating is done with. I don't know sufficient about them to rate your chances, but it must be worth a go. But be aware - one heavy footfall and they're gone in a flash.
BWs, Neil

More Dukes

Another good (but not huge) count of Duke of Burgundy (82) on the Downs near Storrington today, but I didn't have time to visit all of the known colonies, and never made it to Kithurst Hill. A larger count was precluded by long periods of cool cloudy weather, so I'm still yet to fully assess the emergence this year. Male butterflies are still hatching, so I think we're still a day or two before peak season.

That’s great news, Neil. When you think of the dire situation with Sussex Dukes ten years ago. Storrington was yet to get going when I was there a couple of weeks ago, but things change so quickly this time of year, given a bit of sunshine.

Thanks for that Neil ,I,m down that way anyway in June (for Club-tailed Dragonfly) so may well still have a look ,we,re
hopefully going to try Knepp and maybe have a look for Black Hairstreak at Ditchling as well ,thanks for the information Neil !
Regards Allan.W.

Great to hear that the Dukes are doing so well with you. You have taken some stunning photos.

Neil Hulme wrote:...Male butterflies are still hatching, so I think we're still a day or two before peak season.

That's quite something given that the first ones emerged in early April. I guess that cool spell between Easter and the second week in May has retarded them somewhat?

Hi Mark and Nick. The recovery of the Duke of Burgundy in Sussex is a real conservation success story - these days I occasionally count more adults sitting in a metre square than were seen in the entire county during 2003. The great news is that the species is now spreading and its future looks secure in Sussex.

Hi Allan. Good luck with the Clubtails. I sometimes see one or two on the Downs in May, before they return to the rivers; there were three in Kithurst meadow last year! Here's one I found in the upper reaches of Rewell Wood a few years back.
Hi David. Although the Duke of Burgundy season appears very long on a national basis, there is a strong local effect involved. Noar Hill has a southwesterly aspect and is far inland, which means that the very warm microclimate (and strong population) triggers the very early appearance of 'early bird' individuals. Aside from a handful of males, the species didn't really get going in Sussex until May, so we can expect the last adults to be flying in early/mid June.

BWs, Neil

Thanks Neil ,i'll settle just to see one or two on the wing! that'll do me ! …………………. a picture would be a real bonus !!
and that's an excellent one ! Regards Allan.W.

Neil Hulme wrote:...Although the Duke of Burgundy season appears very long on a national basis, there is a strong local effect involved. Noar Hill has a southwesterly aspect and is far inland, which means that the very warm microclimate (and strong population) triggers the very early appearance of 'early bird' individuals. Aside from a handful of males, the species didn't really get going in Sussex until May, so we can expect the last adults to be flying in early/mid June.

Thanks for the explanation, Neil. Good to know they'll be around for a couple of weeks yet.