Thursday, June 2, 2016

Prospects for the 2016 Purple Emperor Season

My predictions for the forthcoming season -

1  They're unlikely to start before 1st July, as larvae came out of hibernation and commenced feeding late due to the cold April, and have since been further held up by periods of cold weather.  This timing could change if we get a very hot June, so there is a chance of the first males appearing at early sites in late June (e.g. in Sussex and Surrey).  

At present, larvae at Knepp in West Sussex are only in the early to mid stages of the final instar - they need another week of feeding, time to pupate, and then an average 18 days as pupae.  

2  Numbers may not be high because last year's egg lay was poor, larval mortality in the autumn was unusually high, there was another pulse of mortality in late winter, and spring was fairly inclement (with many cold evenings, which inhibited feeding).

But much depends on flight season weather and I predicted a poor emergence in 2013, only for the butterfly to emerge in remarkably good numbers.  Also, there's no such thing as a bad Purple Emperor season: other species have bad seasons, this one only deals in superlatives... 

Watch this space for updates...

Here's a mid-final instar larva I found at Knepp on Monday (named 'Sir Vauncey Harpur Crewe' after the most barking mad and OCD collector of all time...) -

1 comment:

Heiko W ittje said...

Here in Lower-Saxony (in a forest named Hasbruch) I followed 3 larvae through winter. Today I found one pupae.