Clouded Yellow
Colias croceus
National Status
True migrant and regular visitor to the UK and West Midlands. Population trend 10 years to 2016 -57%; since 1976 +734%
West Midlands Status
Widely distributed throughout the area. Population trend 10 years to 2016 - decreasing.
Clouded Yellow was recorded in 576 squares in 2026
10 Year Trend Analysis
Habitat
Lucerne and clover fields including improved grasslands.
Caterpillar Food Plant
Clovers (Trifolium spp.), Lucerne (Medicago sativa) and occasionally Common Bird's-foot-trefoil (Lotus corniculatus).
Life Cycle
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |||||||||||||||||||||||||||||||||||||
| Egg | ||||||||||||||||||||||||||||||||||||||||||||||||
| Larva | ||||||||||||||||||||||||||||||||||||||||||||||||
| Pupa | ||||||||||||||||||||||||||||||||||||||||||||||||
| Adult | ||||||||||||||||||||||||||||||||||||||||||||||||
Flight Period
Migrants from North Africa and Southern Europe can arrive as early as April although May is more typical. The first offspring emerge in June and July and in exceptional years there is a further brood
First/Last Sightings 2026
| First Sighting | Recorded by | Last Sighting | Recorded by |
| 7 April | Hasenauer, Mary | 19 October | B Daniels |
Distribution Map
Key
Total number of sightings per tetrad
Hotspots
Anywhere food plants are present.