Garden Butterfly Survey sheets for 2021

Peacock butterfly as seen in Westbury flying on 2nd February 2021.  Another was seen on 8th January and was barely able to fly!  They hibernate as adults in sheds and wood piles and can come out at any time during the winter if there is a sunny warm spell.  They will have returned to hibernation quite quickly at the moment.

Butterfly Recording in Westbury Gardens:  a number of people have been recording the butterflies they see in their gardens each week from Week 1 starting on the 1st April to week 26 starting on 23rd September.   The scheme started in 2006, so there is an increasingly long run of data.  If you want to join in download the attached two forms – April to June, and July to September.  At any suitable day in the week count the largest number of each species of butterfly that you see in your garden at any one time.  This means that you cannot count the same one twice.  For example you might see 4 meadow browns and one small tortoiseshells on the lavender one afternoon and the next day 3 small tortoiseshells and a meadow brown on the same lavender. You would put 4 for meadow browns and 3 for small tortoiseshells in the week of the observations onto your sheet.  Return the sheet to Peter Bright at the end of September either in digital form or as a piece of paper.

2021 April to June Blank recording form      2021 July to September Blank recording form

Westbury Butterfly of the Week 29th April 2020


Green-veined white: It looks like a cabbage white but isn’t. They over winter as pupae which emerge in April and lay their eggs on wild relatives of cabbages – garlic mustard, charlock, lady’s smock and other wild brassicas. In gardens they may use nasturtiums and Alyssums. The offspring of the butterflies flying now emerge in July or August and their offspring, in turn, will become the overwintering pupae. The butterfly is the size of a small white but on the upper side of the forewings the black on the wing tip goes round the point of the wing. In the small white it is only on the front edge. The underside of the hind wing has veins heavily dusted with black and yellow scales giving the ‘green veins’ in its name. Compared to the ‘cabbage whites’ both large and small, they are much more commonly seen out in the wider countryside though they do pass through gardens on their wanderings. The whites seen on the top of Mendip are more LIKELY to be green-veined whites whereas in your garden cabbage patch, it is the other way round. See Butterflies of the Week for 6th May.

Photos John Ball   Peter Bright

Butterfly of the Week 22nd April 2020


Holly blue: This little piece of flying sky is a butterfly of woods, hedgerows and gardens. The female has broad black borders to the wings, while those of the male are clear blue and resemble the common blue. It can be distinguished by the silver with small black spots undersides of the wings whereas the common blue has the underside brown with black and orange spotting. More useful is that the holly blue, being a butterfly of trees and bushes, flies much higher than the common blue that is a butterfly of meadows and stays close to the ground – usually!    The holly blue is unusual in having two generations a year where the caterpillars of each generation have different food plants. The adults flying now, in the Spring, have emerged from pupae that have overwintered. After mating the females lay eggs on the flower buds of holly. The caterpillars will eat the flower buds and such damage can be seen. After two or three weeks as a pupa hidden in leaf litter the adults emerge. This generation emerges in July and lays eggs in the flower buds of ivy. It is the pupae from these caterpillars that will over winter. This butterfly should, really, be called the holly and the ivy blue!

Photos  Robert Maxwell Wood

Butterfly of the Week 15th April 2020




Orange tip: This butterfly is a delightful harbinger of spring. It over winters as a pupa on dead low growing vegetation near its favoured food plants. These are Lady’s smock – a pale pink flower of damp meadows and roadside verges or the white flowered weed, Garlic mustard, found in all sorts of disturbed ground. The males with their orange tips are conspicuous and travel long distances seeking out the females which do not have the orange tips but do have the same green-seeming network on the underside of the hind wings. When the butterflies roost, this green netted underwing provides excellent camouflage.   Females will often be found near suitable egg laying sites where the food plants are relatively large, and in unshaded, isolated but sheltered sites. It has only one generation each year so the pupa formed in June will hibernate until the following spring.

John Ball   Sean Pritchard   Peter Bright

Butterfly of the Week 1st April 2020


Peacock:  The adults that are seen in this week went into hibernation last August/September/October in our garages, woodsheds, log piles. Last autumn they fed avidly on the nectar of flowers like Buddleia and Michaelmas daisy to build up the fat stores they need to see them through to the spring. They can be seen on the wing at anytime through the winter if there is a warm spell after which they return to hibernation. They come out of hibernation at the end of March or beginning of April. The males currently are seeking out suitable territories perhaps near suitable large clumps of nettle that are sheltered but in full sunshine that are favoured egg laying sites. Passing females are pursued and mated with.   Eggs will be laid from late April through into May.

Peter Bright photo