August Wildlife Watch with Cornwall Wildlife Trust

A monthly blog by the Cornwall Wildlife Trust on what wildlife to see and where: this month spot the Yellow Clouded Butterfly, the Leatherback Turtle and Heath Lobelia...

Clouded Yellow Butterfly
The clouded yellow butterfly (Colias croceus) is an annual, if irregular migrant species which visits Cornwall each year from southern Europe. The first migrants of this species usually reach Cornwall in May or June, and these will produce their first ‘British’ broods in August, swelling numbers in the county this month. These butterflies cannot survive the British winter, however, and so most will head back south at the end of the summer.

The clouded yellow can be found almost anywhere, in fields, gardens or waste ground. It is almost always associated, however, with fields of clover (Trifolium sp) or Lucerne (Medicago sativa) or other similar flower-rich habitats. They are best looked for in coastal areas later in the month when, if conditions allow, large numbers may be seen emigrating back towards the continent, perhaps somewhere like our Penlee Battery Nature Reserve.

Leatherback Turtle This month may also bring the leatherback turtle (Dermochelys coriacea) to our shores. Cornish sightings of the leatherback turtle are thought to be due to a deliberate seasonal migration, with most of sightings being recorded between August and October. These incredible creatures, often growing to over two metres in length, breed on tropical beaches but deliberately migrate thousands of miles to feed on the abundance of jellyfish supported by our colder waters - indeed, significant numbers of jellyfish have been sighted in Cornish waters recently.

Leatherback turtles are critically endangered and are threatened not only by accidental entanglement in fishing gear, but also by ingesting marine litter such as plastic carrier bags and balloons, probably mistaking them for jellyfish; as such, its vital that we learn more about the movements of these amazing animals. Best looked for on warm, calm days from along or above the coastline, maybe from somewhere like our nature reserve at Ropehaven Cliffs.

Heath Lobelia
The heath lobelia (Lobelia urens) is a very rare plant in Cornwall, and indeed more widely across the UK, where it is only found on a few sites across southern Britain. Heath lobelia is a fairly tall plant, growing up to 50cm in height, with beautiful blue flowers that open in open spikes during July and August. These delicate flowers are only about half an inch long.

The heath lobelia favours low-lying terrain, often along valley bottoms, especially where the soils are seasonally water-logged. A Red Data Book species, the wet heathland at our Redlake Cottage Meadows Nature Reserve is therefore managed with this plant specifically in mind. Redlake is in fact the only place in Cornwall where this plant is found.

Cornwall Wildlife Trust is the leading local charity working to protect Cornwall’s wildlife and wild places, on land and at sea. If you love Cornwall’s wildlife you can help them protect it by joining as a member, visit website