Thursday, March 18, 2010
Thursday, March 4, 2010
Incidentally, the majority of iris sites are not SSSI (Alice Holt isn't for a start) - I looked into that a while back and think I came up with a figure of less than 40% SSSI. But like Piers - and this is the really important bit - I naturally want to see the best in all people who are captivated by this most enigmatic insect and am tired of the divisions that exist within our passion, although they emanate largely from untoward incidents like this.
Tuesday, March 2, 2010
I must also report that a maximum of five larvae have been removed from my subsidiary study site – the secateurs cut marks are all too obvious. I was following only a few larvae here, though the survival rate was higher, providing a useful comparison with the main study locality.
Whoever did this must have spent a lot of time searching, as a planned operation rather than a piece of opportunism. Many of the markers were far from obvious, and most were on branches from where larvae had long been lost. Several marked feeding locations of 2nd generation Poplar Hawk Moth larvae which I followed in order to see whether they made it through to pupation (some did). For what it is worth, this removal of larvae is illegal, as the site is an SSSI, and the activity is also against the owning organisation’s bylaws. But the law is often an ass, and is even more regularly made into an ass.
Obviously, it is bitterly disappointing that some people interested in Purple Emperors are prepared to take advantage of work that will assist our understanding of this butterfly, especially when the work is being carried out in an open, giving manner, with regular reporting via this website. They must consider personal possession far more important than effort aimed at assisting the insect’s conservation, and people’s understanding of the butterfly. The ruthlessness here is astounding, as is the utter selfishness. But some people seem to live outside of shame and without conscience or integrity.
It might not be right to assume that the collected larvae will end up as set specimens – assuming they produce imagines. They might have been collected for sale as pupae, or to provide photographs of pristine specimens (the females hang around for photo calls but the males tend to ascend instantly). It would be marvellous if they had been collected by someone incensed at Oates’ apparent intransigence in not protecting these larvae from predators! In which case, rest assured that I wanted to place little pieces of netting round every one, and have lost sleep through not having done so in the interests of science.
The truth is that this butterfly does attract some odd – and at times downright nasty - people, and generates some most bizarre behaviour (as this website wondrously illustrates). Also, more than anyone else I know how addictive Apatura iris can be - but such is humanity’s relationship with the heady combination of elusiveness and beauty. Furthermore, I understand the appeal of butterfly collecting better than a great many butterfly enthusiasts do, and am decidedly neutral over the collecting of aberrations, partly because I rather miss meeting old boys out on the downs in search of syngrapha or whatever. It is, though, sad that what integrity there was has all but gone out of butterfly collecting, leaving only rottenness. But of course, the collecting of specimens can now be done in a benign way, through photography. It has moved on wondrously.
I have of course removed, albeit belatedly, markers from all locations that have held or still support Purple Emperor larvae at both my study localities. The study will continue, and I look forward to reporting on it further, to the benefit of everyone who loves this butterfly, irrespective. One of the aspirations behind the setting up of the Purple Empire Website was the, perhaps naïve or vain, hope of bringing all people interested in this butterfly closer together, whatever their perspective. The incident described above rather makes that aspiration unrealistic, which saddens me deeply. We can do better.
February started with 32 larvae in hibernation at my main study site. None had been lost during the first 17 days of January but then four went missing during the last 14 days of that month (to assumed predation) and another desiccated and perished.
I can report that eight were lost to assumed bird predation during February and one more to ‘desiccation’. 24 are now extant.
So far this winter, 16 larvae have been lost to apparent predation. It is highly unlikely that any of these have moved position, given the cold weather.
Since mid January the (apparent) predation rate has been running at circa two per week, and may well be increasing. There is a distinct predation hot spot in a central area of the site, from where nine out of 12 hibernating larvae have vanished to assumed predation. This area is alive with flocks of tits, more so than the rest of the wood.
So far this winter 16 larvae have succumbed to apparent bird predation, of which 14 were on buds and two on scars on stems. We have no idea how normal this is as there is no base line data – this is the base line. I need to do comparable studies over several winters. Two have died due to ‘desiccation’, a phenomenon well known to those of us who breed iris.