A collaboration of coast and countryside organisations on The Lizard Peninsula

Butterflies on The Lizard

Red Admiral
As ever with butterfly spotting the likelihood of finding a good diversity and number on the wing depends on the weather on the day, and the weather in preceeding weeks, months and years. There is plenty of protected wide open flower filled space on The Lizard, so given the right conditions numbers of some species should be good.

Marsh Fritillary Survey - Spring 2015

Earlier in the year, researchers from the University of Exeter’s Environmental & Sustainability Institute (ESI) conducted surveys and research on the Marsh Fritillary butterfly on the Lizard (see  http://www.the-lizard.org/index.php/article-archives/butterflies-moths/513-butterfly-surveys-in-march-your-help-pleas).
The larvae were found on 5 sites, but because this butterfly is so rare nationally, the Lizard populations are now very important at both the county and country level. However, they were not found on one small site which they were known to frequent until very recently.

A small cluster of larvae in early springA small cluster of larvae in early spring. ©Chloe Lumsden

Butterflies at Windmill Farm Nature Reserve

My main interest is birding; however I enjoy all the diverse flora and fauna that can be found on the Lizard. Summer is a relatively quiet time for bird rarities, but there is still plenty to see on the wing. This article highlights some of the fantastic butterflies that can be found on the Lizard. I am not a butterfly expert! All the pictures were taken at Windmill Farm National Nature Reserve; however, most of the species can be found all over the Lizard.

The first species contradicts my last statement as it is only found in a couple of places on the Lizard – Windmill Farm being one of them. This is the nationally rare and beautiful Marsh Fritillary, which can be seen in June and early July  they always lay their eggs on Devil’s-bit Scabious.


Marsh Fritillary 

Marsh Fritillary

Clouded Yellow 

Clouded Yellow

Butterfly conservation reaches new heights

A larval web in March 2016As spring came around this year, researchers from the University of Exeter’s Environment and Sustainability Institute were once again busy conducting surveys across the Lizard for one of our nationally rare butterflies, the marsh fritillary Euphydryas aurinia. The mission? To better understand the habitat requirements of this declining butterfly, with the ultimate goal of developing meaningful management practices to conserve these important populations for the future.

In March the black caterpillars can be seen basking and feeding together within silken webs near to their hostplant Devil’s-bit scabious Succisa pratensis. Extensive surveys for these conspicuous webs revealed populations at 8 sites (see here for last year’s survey). Although this is good news, populations can fluctuate largely from year to year and remain very sensitive to changes in climate and habitat. So we must obtain a sound understanding of their habitat requirements in order to give them the best possible chance...

Butterfly season begins!

It was with eager anticipation that I awaited the beginning of April this year – the start of the butterfly recording season for those of us who walk a set route regularly, noting down the butterflies we see. The route I walk (called a transect), once a week from April to the end of September, is on the south-western fringe of Goonhilly Downs in the centre of The Lizard peninsula. My enthusiasm was slightly dampened by the weather conditions – cold and wet, not conducive to butterflies taking to the wing!
During the first four weeks of walking the transect I have only seen three species of butterfly: a rather tatty and faded Peacock, which probably overwintered somewhere close by; a freshly emerged speckled wood and a green-veined white fluttering around a cluster of primroses. Despite this, however, I have enjoyed walking the route again, passing through some beautiful woodland, heathlands and fields, with their hedges coming into leaf. I been fortunate to see a young fox emerging from the heather, as well as snipe, and hear the sound I associate with Spring, a chiffchaff calling from a nearby tree.

Speckled WoodSpeckled Wood

I started walking this transect in July last year so have yet to have the enjoyment of seeing the Spring and early Summer butterflies that use the various habitats that this transect passes through. I am excited to see what fritillary butterflies are still in the area; small pearl-bordered fritillaries, dark green fritillaries and marsh fritillaries have been recorded here on the heathland in the past, as well as the impressive silver-washed fritillaries in the wooded areas. I spotted a number of the silver-washed fritillaries last year, as well as the purple hairstreak, which is usually hard to see as it flies high up, above the canopy of oak trees. I was fortunate to be in the right place, at the right time, when one flew down and landed on a bramble leaf a few metres away from me. That’s the beauty of looking for and recording butterflies, you never know what you may encounter!

Butterfly Surveys in March!! Your Help Please

Catrpillars and their web on devils-bit scabiousBelieve it or not, right now is the best time to survey the population health of one of our most notable butterflies – the marsh fritillary. Admittedly, surveyors will not be looking for butterflies on the wing but they will be taking advantage of the occasional sunny but not too warm day to spot basking caterpillars.
This spring, ecologists from the Environmental and Sustainability Institute (ESI) at Exeter University are undertaking a survey of Marsh fritillary butterfly colonies on The Lizard. This attractive butterfly is one of the most rapidly declining butterfly species in Europe, principally because the damp meadow habitats it frequents have been increasingly drained for agriculture. Scrub encroachment through lack of management and climate change are also factors in its recent demise.

Marsh fritillary caterpillars ‘spring’ into action!

Catkins may have appeared on the willow and the blackthorn may be flowering but the sign of spring I look forward to most is spotting the bristly little black caterpillars of the marsh fritillary butterfly basking together on freshly spun webs!

Marsh fritillary caterpillars

Marsh fritillary caterpillars

These caterpillars have spent the winter huddled together in a spun ‘nest’ deep down in the vegetation and, during the first warm days of spring, they reappear to spin a new communal web on the leaves of devil’s-bit scabious (Succisa pratensis) - the food plant of the caterpillar. They construct a communal web and cluster together to form a black ‘mass’ which can more efficiently absorb the sun’s warmth and raise their body temperatures in order to seek out and digest food. I have also found larval webs constructed on the stems of grasses, but scabious is never far away, with caterpillars basking on both leaves, grass and mosses.

Marsh fritillary caterpillarsMarsh fritillary caterpillars

Marsh fritillary Survey 2016

Marsh Fritillary caterpillars - copyright  Pete Eeles Marsh Fritillary Report Card

Over the last two years, researchers based at the Environment and Sustainability Institute, University of Exeter have been undertaking surveys and research on the Marsh fritillary on the Lizard. Our main conclusions are that this butterfly remains extremely localised (occurs on only a handful of sites) and vulnerable to extinction. We have recently produced a report card which summarises our knowledge about the Marsh fritillary, and how best to manage the Lizard landscape for its continued survival. This document is uploaded onto the website, so please take time to read it and hopefully it will inspire you to go out and look for the autumn webs, which while are not as attractive as the adult butterflies are interesting nonetheless.

Saving the Lesser Butterfly Orchid

The Lesser Butterfly Orchid (Platanthera bifolia) is one of the focus species of the groundbreaking Back from the Brink project. This project aims to save 20 species from extinction and benefit over 200 more through 19 projects that span England – all thanks to funding from the National Lottery and People’s Postcode Lottery.
The once widespread Lesser Butterfly Orchid is one of the fastest declining species of plant in the UK and has disappeared from 75% of its recorded range in England.

The project aims:
• To identify and manage key sites where the plant occurs in the South West of England and increase the populations.
• To better understand the reasons for decline.
• To increase public awareness of the plant.
• To engage and involve the public in its protection

The importance of temperature for rare butterfly

Exeter University research investigates the importance of temperature for rare butterfly.
2019 is proving to be a year of climatic extremes. Hot, sunny weather back in February saw the mercury hitting 20°C in some parts of the country, while in July the UK’s all-time maximum recorded temperature was exceed with a new record of 38.7 °C. Current research at the University of Exeter is helping to uncover how temperature affects our wildlife, with a special focus on one of the Lizard’s threatened species butterfly.

A male Silver-studded Blue butterflyA male Silver-studded Blue butterfly

The Silver-studded Blue is a scarce butterfly in Britain, that can be found on the heaths and coastal grasslands of the Lizard. Elsewhere in Cornwall, it also occurs on sand dunes and some of the former mining sites in the region. This butterfly has a rather unusual lifecycle in that it has a special relationship with certain species of ant. The caterpillars produce a sweet, sugary liquid to reward ants, which in return protect it from predators and even let it live inside their nest. Because of this close association between butterfly and ant, Silver-studded Blues can only be found in places where the right species of ant occurs at high enough densities.

A black Lasius ant – the host species associated with Silver-studded BluesA black Lasius ant – the host species associated with Silver-studded Blues

Our research is investigating how both habitat conditions and temperature constrains the distribution of the butterfly and its associated ants. Temperature can vary greatly on a scale of centimetres or metres due to the influence of topography and vegetation. For small, cold-blooded insects, this fine-scale variation in “microclimate” can be very important in determining where they can and can’t live. We are studying this relationship with temperature at sites across Cornwall, looking at where the Silver-studded Blue and its host ants can be found, and what the habitat and microclimate conditions are like in these locations. One such site is the National Trust’s Penrose estate, where we are also looking at how the activity of Silver-studded Blues varies with different weather conditions and the time of day. This should help to give us a more mechanistic understanding about how environmental conditions directly affect the butterfly. By better understanding the factors important for allowing species to persistence within landscapes, we can improve our ability to predict how these species are likely to respond to future environmental changes.

Published: Sept 2019
Author: Marcus Rhodes (Exeter University)