The first Purple Emperors

GH, LN and BG walked transect 15 choosing a morning just before the third heatwave of the summer rolled in. Even then, our walk-around certainly felt warm in the constant sun with barely a breeze.

The butterflies, however, were loving it. We recorded another very busy count with an exceptional 728 individuals, our third highest since 2019. The sudden drop-off in Marbled Whites was more than compensated by the dramatic surge in Gatekeeper numbers, leaping from 88 last week to a remarkable 305. The Meadow Browns have held at a roughly constant high level for the past three weeks, and we saw increased levels of Small Whites, Common Blues and Silver-washed Fritillaries.
A special highlight came while observing the Purple Hairstreaks flitting about Hill Wood Field’s trees.  Liz was suddenly distracted by spotting a large high-flying butterfly that she identified as a Purple Emperor, and moments later Graham H confirmed a second one as it flew over our heads. These two sightings were the first Purple Emperors ever recorded on our transects since we started back in 2016.

Count details:
​ 305 Gatekeeper
174 Meadow Brown
  47 Common Blue
  38 Ringlet
  34 Large White
  30 Marbled White
  26 Small White
  14 Silver-washed Fritillary
  12 Purple Hairstreak
  11 Small/Essex Skipper
  (inc. 1 Small and 2 Essex Skippers)
    9 Brimstone
    7 Dark Green Fritillary
    6 Comma
    5 Speckled Wood
    3 Small Copper
    2 Peacock
    2 Purple Emperor
    2 Purple Hairstreak
    1 Brown Argus
Count summary:
728 butterflies from 18 species.
​For more info on these species visit
​ butterfly-conservation.org

Couples of the week

Common Blues  (Polyommatus icarus)
Caught in a quiet moment, this pair of Common Blues is doing what summer butterflies do best – ensuring the next generation.

• When their wings are open, males are bright sky-blue, while females are often brown with a dusting of blue – making them trickier to identify.
• Mating can last up to an hour, and the female stores sperm to fertilise eggs over several days.
• Their caterpillars have a surprising ally: ants often ‘farm' them, protecting them in exchange for sugary secretions.

Love, protection, and ant partnerships – all in the life of a Common Blue!

Common Blues - Liz North

Large Whites (Pieris brassicae)
This elegant duo of Large Whites, often called ‘cabbage whites’, is doing more than dancing – they're continuing a legacy of garden notoriety.

• Female Large Whites can lay over 600 eggs in their lifetime, often on brassicas like cabbage, kale, and broccoli – hence their fame (or infamy) with gardeners.
• Mating takes place soon after emergence, with males transferring a waxy plug to prevent the female from mating again.
• Their caterpillars are gregarious and toxic to predators, thanks to the mustard oils in their host plants.

Romance, strategy, and a touch of chemical warfare – this couple is anything but ordinary.

Large Whites - Liz North

Gatekeepers (Pyronia tithonus)
This affectionate pair of Gatekeepers isn’t guarding anything – except perhaps the summer hedgerows they call home.

• Males are often seen basking in sunny spots along paths and field edges, defending small territories with surprising zeal.
• Courtship is brief: males patrol and pounce quickly, and if the female is receptive, mating may last several hours.
• Unlike many other butterflies, Gatekeepers have two small eyespots on each forewing, possibly helping to deter predators by mimicking larger animals.
• A familiar sight in high summer, these fluttering ‘gates' to the countryside are as romantic as they are territorial.

Gatekeepers - Liz North

Survey by Brian G, Graham Harris and  Liz North submitted to Butterfly Conservation (UKBMS).
​ ​Report by GK, BG & AI.