Transect 17 tops 1,000 butterflies

On Transect 17, walked on Saturday 25th July, GH, LZ and BG were joined for the second time by Luka Mehew, who proved very useful for the day's busy counting. 
The weather was hot and quite humid, just right for a further surge in butterfly numbers to our second-highest ever transect count of 1,153 butterflies from 22 species (beaten only by our remarkable Week 14 total of 1,207 butterflies in 2019).
Once again, it was the prolific Meadow Browns who, with a count of 659, more than doubled their previous (2019) high of 299. Equally impressive were the 193 Common Blues, which in other years have struggled to reach 3-figure totals.
The ‘specials' continued: there were 6 Clouded Yellows (our first sightings for 4 years), a rare sighting of a Small Tortoiseshell, and our first Silver-spotted Skipper of the year.
Record numbers and notable rarities made Transect 17 one of the highlights of our outstanding 2026 butterfly season.

Count details:
​659 Meadow Brown
193 Common Blue
136 Gatekeeper
56 Small Heath
39 Chalkhill Blue
12 Small Copper
11 Small White
10 Purple Hairstreak
9 Brown Argus
6 Clouded Yellow
5 Silver-washed Fritillary
3 Red Admiral
3 Small Blue
2 Comma
2 Large White
1 Brimstone
1 Dingy Skipper
1 Holly Blue
1 Painted Lady
1 Silver-spotted Skipper
1 Small Tortoiseshell
1 Speckled Wood
Count summary:
1,153 butterflies from 22 species.

Small Tortoiseshell (Aglais urticae) – pictured above.

• Once one of Britain's commonest butterflies, the Small Tortoiseshell has declined sharply in many parts of the UK, making each sighting increasingly special.
• Females lay their eggs in large batches on stinging nettles, where the caterpillars live together in protective silken webs before dispersing.
• Adults are long-lived and can hibernate through the winter in sheds, garages, hollow trees and other sheltered places, emerging on the first warm days of spring.
• When to see them in the UK: Typically March-October. Overwintered adults appear from March-May, followed by a new generation from July-October.

Others on the wing

Mating Chalkhill Blues - Liz North

Silver-spotted Skipper - Liz North

Clouded Yellow - Liz North

Click on photos to enlarge. If you would like to know more about any of the butterfly species mentioned, visit ​butterfly-conservation.org

This week's survey by Graham Harris, Liz North, Brian Gardner and Luka Mehew submitted to 
​Butterfly Conservation (UKBMS).
​Report by GK, BG & AI. Header photo of Small Tortoiseshell by Liz North.