Butterfly Conservation Ireland

It is great to have some positive news to report. Butterfly Conservation Ireland’s reserve at Lullybeg has benefitted from a generous grant provided by Kildare County Council and the Department of Housing, Local Government and Heritage (NPWS). This article describes the reserve and explains how the grant has been applied to fulfil our conservation objectives.

Lullybeg Nature Reserve is a Bord na Móna rehabilitated cutaway, managed since 2010 by Butterfly Conservation Ireland (BCI). It is listed in the Bord na Móna Biodiversity Action Plan 2016-2021. It is described as a site of national importance in the Kildare County Development Plan 2023-2029. The reserve contains a butterfly transect walked up to 26 times each year between 1 April and 30 September. The records for the transect have been sent to the National Biodiversity Data Centre each year from 2008-2023. A report concerning the transect is published on the BCI website annually as part of the Annual Report.  Lullybeg Reserve is bounded by plantation forestry to the north and east and bare peat to the south and west. It lies on both sides of a waterway that is part of the Crabtree River.

The site contains several habitats existing as complex mosaics. Habitats found on the reserve include tall herb swamps, ponds, marsh, wet grassland, dry-humid acid grassland, dry calcareous and neutral grassland, wet heath, poor fen and flush, scrub and bog woodland. This is an important conservation location (rated Nationally Important) as it is home to a population of Marsh Fritillary Euphydryas aurinia, the only protected species of butterfly in Ireland (protected under Annex II of the Habitats’ Directive 1992). Other important butterflies present are Dark Green Fritillary Speyeria aglaja (ranked Vulnerable), Wall Brown (ranked Endangered) and Small Heath Coenonympha pamphilus (ranked Near Threatened). Twenty-six butterfly species have been recorded on the reserve.

The rewards of conservation management and scrub removal/control are evident as the already impressive list of flora and fauna recorded on site is increasing. As stated earlier, the site is used as a transect for the Irish Butterfly Monitoring Scheme (IBMS) run by the National Biodiversity Data Centre, with 15 years of IBMS records underlining the site’s importance for Lepidoptera.

Moths that are present on the site include species ranked Near Threatened on the macro-moth Red List published by the National Parks and Wildlife Service in 2016 (Allen et al. 2016), such as Small Chocolate-tip Clostera pigra, Dark Tussock Dicallomera fascelina, Small Purple-barred Phytometra viridaria, and species ranked as Vulnerable, such as Narrow-bordered Five-spot Burnet Zygaena lonicerae. Birds such as Teal (Amber-listed), Woodcock (Red-listed), and Snipe are among the breeding birds present. Merlin (Amber-listed), Buzzard, Kestrel (Red-listed), Sparrowhawk, Jay, Raven, and Linnet (Amber-listed) occur here.

The conservation work required consists mainly of scrub control and cattle grazing. Scrub must be controlled to maintain plagio-climax vegetation of flower-rich grassland, wet heath and fen with low scattered scrub over much of the eastern half of the reserve. The work of scrub control is labour-intensive and is done by hand and using power tools. Grazing is a vital conservation tool for maintaining grasslands for butterflies, moths and other invertebrates. A range of sward heights and periodic substrate disturbance is vital for habitat maintenance. To contain the livestock effectively, fixed and movable fencing is needed, as well as a safe, clean water source.

The National Parks and Wildlife Service is aware of the reserve and its importance. NPWS held a Marsh Fritillary survey methodology training day on the reserve, led by the state entomologist Dr. Brian Nelson. Butterfly Conservation Ireland’s Board of Directors includes Mr. Kieran Buckley recently District Conservation Officer for NPWS in County Kildare.

An annual report is written to describe the butterfly abundance trends on the reserve. These reports, titled Lullybeg Reserve Report, can be found under the Annual Reports tab on the Butterfly Conservation Ireland website. The most recent report, from 2022, can be found here:

https://butterflyconservation.ie/wp/report/butterfly-conservation-ireland-annual-report-2022/

Grant Expenditure

The grant aid, processed by Bridget Loughlin, the Heritage Officer in Kildare County Council was applied to the purchase of materials to manage the reserve. The fencing materials bought were conduction tape, fence posts, an electric battery, and a fencer. These were used to erect mobile fencing in the northeast section of the reserve in preparation for grazing by cattle.

In addition, fixed fencing containing gates were installed along the front of the reserve to ease access for visitors and to make delivery of livestock to the reserve more manageable. An information board was produced to introduce the reserve and acknowledge the support of Kildare County Council and the Department of Housing, Local Government and Heritage (NPWS).

The addition of the drinking trough and pump means the livestock have access to clean drinking water, making it more attractive to the farmer who provides the cattle to graze the site.

The power tools purchased, chain saws, pole saw, strimmer, and hedge trimmer will enable BCI to manage the reserve. The strimmer has been used to cut the vegetation under the fence to prevent it from interfering with the electric current. The chain saws have been used to clear an area of dense scrub to extend the grassland and reduce shading in an area that has the potential to host the Marsh Fritillary butterfly.

The pole saw and hedge trimmer will help BCI maintain the habitat by keeping developing scrub under control. These tools have a long reach making the dense scrub easier to tackle.

Safety equipment to operate the tools safely supports BCI’s volunteers.

Fencing is installed with gates to allow visitor access and is convenient for cattle delivery to the reserve. Photos 26 October 2023.

BCI expects the support provided to assist us in protecting this very important reserve. The latest data published in the Irish Butterfly Monitoring Scheme Newsletter by the National Biodiversity Data Centre concerning butterfly abundance is deeply concerning (Judge and Lysaght 2023).

Results from the multi-species index of the 15 most common butterfly species highlight that there was a moderate decline (-57%) in the population of butterflies in 2022 when compared to the baseline year of 2008.

It is important to note that the multi-species index is a useful index to show overall trends in population changes of common butterflies of the wider countryside. However, it does not generate sufficiently reliable data to track how the populations of our more localised or specialised butter-fly species are changing. This is because there is currently not enough data being recorded for these species. In order to capture adequate information on these species additional species-specific schemes (like the Marsh Fritillary Monitoring Scheme) are needed.

The Marsh Fritillary is monitored on the reserve and continues to thrive, but there are indications that it is declining elsewhere. The most recent government report to the EU Commission concerning the Marsh Fritillary indicates that it is not in favourable status.

Perhaps of greater importance is the decline of non-specialist butterflies. The 2023 Irish Butterfly Monitoring Scheme Newsletter reports a strong decline for the Ringlet and Meadow Brown, both thriving on the reserve. The decline of common species suggests a deeper, more widescale biodiversity loss.

It is hoped that the management of the reserve will continue to show the way to protect our countryside and species.

Finally, BCI would like to record its gratitude to Kildare County Council Heritage Officer, Bridget Loughlin for her help in processing the grant application, to the Kildare County Heritage Officer Maebh Boylan, and to Kildare County Council and the Department of Housing, Local Government and Heritage (NPWS) for the grant.

Key Reference

Judge, M and Lysaght, L. (2023). The Irish Butterfly Monitoring Scheme Newsletter, Issue 15. National Biodiversity Data Centre

 

October is the last month of the year to see butterflies in any numbers. What can be seen is even more crucially weather dependent, but this year’s October has seen some exceptionally warm weather, with some good abundance figures for the time of year.

We are seeing some unseasonable behaviour. On 14/10/2023 I observed a courtship flight by a Red Admiral pair, and it appeared destined to culminate in mating. The gentle fluttering flight used by both sexes is a sign of female cooperation in this butterfly, and if the pair remained in the lane instead of slipping quietly into an adjoining field, probably to seek shelter from the stiff north-west breeze, I feel sure that I would have observed their pairing.

I have never seen the Red Admiral behave like this in autumn in Ireland, so perhaps we are seeing the species beginning to stay put, even 33km inland, rather than migrating south, the situation that traditionally applies in Ireland. Since the turn of this century, coastal breeding in two areas (Howth, Dublin and Ravenwood, Wexford) during late autumn has been recorded, but not inland, where the colder conditions destroy the Common Nettle.

Painted Ladies were still being seen, inland and on the coast. Like their relatives, their main and probably only nectar source in many areas is our Common Ivy. While they remain, we are holding on to the memories of summer.

Another feature of change that has extended the pleasure of seeing butterflies deeper into autumn is the spread of the Comma, and its ability to produce a second generation in Ireland, a generation that hatches from the pupa in September and October.

This lovely addition to our butterfly fauna can be seen sunning its gleaming orange-red wings on shiny bramble and ivy leaves, feeding on their fruit and flowers respectively. After the feeding is complete, the Comma hides itself in dense wooded cover until spring’s rays warm it to action.

In some woods, a dozen or more will be found in March feeding on a flowering Grey Willow. Slightly later, dandelion comes on stream. By the time this occurs, the males are defending territories and seeking passing females.

What is much less visible is the activities of moth and butterfly caterpillars, many of them still busily feeding before colder weather pauses their activity. Autumn moths are still in flight, such as the Merveille du Jour pictured here. Last weekend I had 19 moth species in my garden trap, a good showing for October, but the night I trapped was very mild.

At this time of the year, sunny, sheltered south-facing hedges containing flowering ivy are the best places to look for butterfly life. In a week or so, even these places will hold little evidence of a fine summer for many of our butterflies, leaving us with our memories but also our hopes for next spring.

Photographs © J. Harding

Time, like an ever-rolling stream
bears all its sons away;
they fly forgotten, as a dream
dies at the op’ning day.

(O God Our Help in Ages Past, Isaac Watts, 1674-1748)

Since humans learned to manipulate the environment to produce food, the natural world has been changing. Some people try to help nature by trying to restore what once was. Conscious not just of nature’s fragility but also of our mortality, the desire to leave something good that will outlast us is a powerful motivation. The following article reviews, briefly, what we have lost, describes efforts to reintroduce lost butterflies, and assesses the validity of reintroductions.

Animal and plant population loss is a common theme across the world. Humans have been radically altering the natural environment for thousands of years, especially since the farming of plants and animals began during the Neolithic period about 12,000 years ago. Mesolithic man was a hunter-gatherer, who moved through the landscape, surviving on food he picked, dug and hunted. There were no permanent settlements, and in Ireland and in other places, he used waterways to reach new areas to find food. Plant and animal domestication made long-term and permanent settlements possible, and humans began to replace natural vegetation with crops and grazing for animals.

Animals that threatened domesticated animals were killed when this was possible, and humans learned to protect livestock using dogs, and walls and by removing habitat for predators. Determined attempts were made to extirpate predatory animals, with rewards offered for proof of kills. The environment we have inherited is quite different from before farming was used to feed people and build civilizations; the pollen records and archaeological evidence show evidence of radically altered ecosystems.

The Brown Bear, the Eurasian Wolf, Wild Boar and Giant Elk are long extinct from Ireland and Britain, with the Giant Elk lost from the world, a likely victim of overkill and perhaps natural climate change. Many habitats are at a fraction of their original extent, and no fully natural habitat exists in these islands and in most of Europe. What these looked like is very difficult to say; there is recent research that challenges the long-held view that woodland dominated our landscapes before humans dominated them. The widespread presence of open grassland invertebrates today suggests that large areas of natural grassland must have existed.

The pollen record is not an infallible guide; some plants produce far more than others and some plant pollen travels further. Scots Pine falls into these categories; we cannot deduce huge pine forests existed simply because its pollen is abundant in the archaeological record. The pollen record does indicate that grasslands existed along with woods.

A mixed landscape of wooded and more open areas is now believed to have existed before the onslaught on forested areas by humans. When we began reafforestation early in the 20th century, we decided to use fast-growing non-native coniferous trees which lack any relationship with the woods we once had, and this approach, recently modified in favour of including some native trees, has continued. The most severe recent habitat loss in this country following the loss of native woods and grassland is our raised bogs, mostly destroyed. I doubt there is a single raised bog in Ireland that is undamaged.

Animals and plants require suitable conditions for their survival. When a species is lost from an area, it is usually because important conditions it needs no longer exist on a sufficient scale. You cannot, for example, plough a field containing wild grasses and herbs and re-seed it with agricultural grasses and White Clover and expect all the original insects it supported to survive.

There are people who dream of landscapes filled with beauty, containing the species we know once existed more widely. We cherish the often-small areas that still hold these natural features and want them protected and restored. Restoration involves returning existing habitats to their best condition, usually through some form of direct management.

Some go further; rewilding is their goal. Rewilding is the restoration of an area of land to its (original) natural uncultivated state; the idea is to remove human influence. In pursuit of these dreams, some people want to return animals that once existed in our environments. This has happened in Ireland, with the state-funded projects to restore the extirpated Golden and White-tailed Sea Eagles and Red Kite. Eurasian Beavers were reintroduced to parts of England and Scotland, many unofficially. Beavers are sometimes admiringly referred to as “ecosystem engineers”. By damming streams, they reshape valley bottoms, creating new ponds and waterways that rapidly fill with birds, amphibians, dragonflies, and other insects and fish. Research also shows how dams filter polluted water, and store huge quantities of floodwater. Beavers’ dams can even prevent towns from being flooded. But the water must go somewhere – and the farmers whose fields are flooded as a result tend to detest these rodent engineers.

One animal group that might be less controversially reintroduced is Lepidoptera, butterflies and moths. Some are easy to breed and easy to introduce. Just to be clear, reintroduction is the intentional movement and release of a species within an area that was once part of its historical range, but from which it has become extinct.

This has occurred in well-organized ways in England, with the reintroduction of the Large Blue (wiped out in 1979) and Chequered Skipper (went extinct in 1977). These reintroductions were underpinned by painstaking research and habitat restoration; the stock for the reintroduction of the Large Blue was sourced from Sweden while the Chequered Skippers were taken in Belgium.

But these were professionally executed and scientifically informed. Some people, however, are impatient with the slow progress of official reintroduction programmes and have decided to do it themselves.

Martin White from Nottinghamshire was a rewilder passionate about the reintroduction of extinct butterflies. He bemoaned the slow pace and cost involved in official reintroductions. He said that his first attempt to reintroduce the Mazarine Blue cost him less than £10. Contrastingly, official programmes cost much more. Transporting the Chequered Skipper to Rockingham Forest, Northamptonshire (north of Milton Keynes) via Eurostar cost £10,000.

White has introduced thousands of butterflies to various places; many of these efforts failed. But some succeeded; he closed a 90-mile gap in the Marbled White’s distribution between the midlands and the Yorkshire Wolds. He reintroduced the Purple Emperor to Lincolnshire. He has introduced the Dingy Skipper onto former mine sites, with success. Some butterflies cannot reach suitable sites because the intervening countryside is so hostile to insects that seek to move. Migrating insects must brave herbicides, pesticides, foodless ground, and long distances to reach areas that have become suitable again. Unless you are a powerful species, like the Red Admiral, the chances of natural recolonisation are very low.

But will these efforts succeed over the longer term? If a butterfly or moth is missing from a site, there is reason for its absence. Unless dealt with, simply releasing fertilised females will not help, even if the larval foodplants still occur on the site. Some species have highly specific needs that extend far beyond the presence of their foodplant. What often seems to happen is that the released butterfly breeds for a year or two before dying out.

What annoys nature reserve managers is the clamour to ‘save’ a reintroduced butterfly that reached the reserve via the car boot. People want to see rarities, such as the Marsh Fritillary or Glanville Fritillary so insist on this one butterfly being accorded conservation priority. This can reach extreme levels of attention. The only known Marsh Fritillary colony in Lincolnshire (courtesy of Martin White) exists in two fields, 100 miles from the nearest colony. The caterpillars are collected by volunteers and replaced on their foodplant after the area is mown. This is certainly not natural, and one wonders what the argument is for artificially maintaining this population. This is a gardening exercise, not a conservation one.

What is perhaps a more serious concern is using butterflies sourced in Europe to reintroduce a butterfly to an area in Ireland or Britain when the species still occurs in these countries. For example, Purple Emperors sourced in Germany were used to re-populate woods in east England. This might be harmful to native populations of the butterfly if pests or pathogens arrive with them. It might also change the genetic makeup of native Purple Emperors, which may have developed the genome to cope with English conditions.

There is evidence that introduced or reintroduced butterflies might create difficulties for other butterfly species. The arrival of the Map butterfly in southern Sweden (which it reached unaided) coincided with increased rates of infection by parasites of two other nettle-feeding butterflies, the Small Tortoiseshell and Peacock.

The three species’ caterpillars overlap in their occurrence, but there are phenological differences (differences in the timing of the hatching of the caterpillars).

The Map might be causing higher infection rates by shared parasitoids by providing a host for the parasitoids when the larvae of the Small Tortoiseshell and Peacock are scarce.

Therefore, there are times in the year when Map larvae are plentiful but those of the Peacock and Small Tortoiseshell are less numerous. Phenological differences in the parasitoids between hosts might also mean the Map is assisting increased infection rates in its butterfly relatives. If correct, the Map is reducing the competition for its food (nettles) during its establishment phase, but if the Map recruits more parasitoids, as the Swedish study indicates is likely, a balance between these butterflies might be struck.

But the study did not look at the parasitoids that the Map may have introduced to the other three butterflies, only looking at shared parasitoids, and looked at larval parasitoids, not egg or pupal ones.

The relationships are therefore not well-known and extrapolation from the Swedish experience may not be possible in another area with different conditions. Therefore, harm might be caused to native populations by reintroducing a butterfly or moth; however, after establishment, a balance might develop as the new arrival becomes subject to biological controls.

This is where the need to investigate impacts arises. The most useful step is to protect existing habitats, restore them where needed and extend them so that populations can move through the landscape. Where large areas of suitable habitat exist whether this is mainly the result of long-term favourable management, restoration, rewilding, or natural processes, then the conditions for the reintroduction of animal or plant species might be reached. Given the state of our habitats, reintroduction might even be necessary.

The severe reduction in the area of the Small Blue’s habitat along the Dublin coastline due to serious coastal erosion, management problems and the creation of golf links prompted an introduction of the species in extensive suitable habitat in County Meath and Louth. This attempt has been very successful. Meanwhile, the donor population has lost about 90% of its original habitat, which has been swallowed by the sea. The remaining population is hanging by the proverbial thread.

If the dune habitat on the donor site is restored by natural or human action, the new populations might return the compliment! This has already happened in England. Black Hairstreak butterflies from Monk’s Wood, Cambridgeshire were used to establish a new population at Warboys Wood. When Monk’s Wood lost its population during the Great War, it was repopulated from its receptor site. The restored Monk’s Wood population still exists to this day!

Considerable resistance to unauthorised, unofficial reintroduction exists and has for some time. It is illegal to introduce an exotic animal into the wild in Ireland and illegal to introduce or reintroduce, without consent, any animal or plant not already present in certain protected areas after a Statutory Instrument has been signed. It is a great pity that this is not the case for non-native plants in the general countryside. Biological recorders resent their maps being compromised by records of unofficially released species. This makes it harder to calculate the true distribution of a species, especially given the often transient presence of introduced species. Others hate the idea, captured in naturalist  Robert Lloyd Praeger’s phrase of ‘forging nature’s signature’, by introducing species in areas where they might never have occurred.

There are very good reasons for not interfering with nature. There are very good reasons for interfering with nature. In the absence of good motives and good research, reintroduction should not be tried. Bad motives include removing rarities from a site because it is about to be destroyed by a development or introducing rarities to a site that is about to be destroyed by a development. Martin White carried out his introductions because he loved butterflies and wanted to leave a legacy, to feel that his life was not a waste. Martin White died on 12 October 2020. He knew his time was coming months before. He was still releasing butterflies in the summer of 2020. Whatever the ecological impacts of his efforts, it is touching to see his drive to see nature flourish.

The damage we have done places a moral obligation on us to atone. Reintroductions might be part of this process. It might be a question of how these are done, not whether they are done. But let’s focus chiefly on looking after our habitats and extending them. Without good, large-scale habitats, many species don’t stand a chance.

 

Key References

Audusseau, H., Ryrholm, N., Stefanescu, C., Tharel, S., Jansson, C., Champeaux, L., Shaw, M.R., Raper, C., Lewis, O.T., Janz, N. & Schmucki, R. 2021, “Rewiring of interactions in a changing environment: nettle‐feeding butterflies and their parasitoids”, Oikos, vol. 130, no. 4, pp. 624-636.

https://www.theguardian.com/environment/2020/oct/13/maverick-rewilders-endangered-species-extinction-conservation-uk-wildlife Accessed 01/10/2023

 

 

 

The extraordinary garden of Robert Donnelly and Jane Doughty boasts enormous butterfly populations, with hundreds of butterflies counted for Butterfly Conservation Ireland’s National Garden Butterfly Survey annually.  On just one day,  27 August 2020, 154 Small Tortoiseshells were counted, feasting on native flowers such as Hemp Agrimony Eupatorium cannabinum. Less frequent garden visitors, such as Cryptic Wood White, Small Copper, Comma, and Silver-washed Fritillary also make Robert and Jane’s garden at Little Eden in County Kilkenny their home.

But Little Eden is not just looking after local butterflies. The garden’s fruit and vegetable yield generated €793.42 from neighbours and passers-by, which Robert and Jane have kindly donated to Butterfly Conservation Ireland. Their help is timely, as we are currently arranging fencing for the front boundary of the reserve in Lullybeg in northwest Kildare to improve the security of the area to ensure grazing livestock needed to conserve the grassland habitats are better contained.

A great thanks to Robert and Jane for all they do for butterflies local and national. The joy of seeing beautiful butterflies in our gardens and beyond, like this Red Admiral, depends on the care for nature shown by Jane, Robert, and all our members and supporters.

Thank you.

 

Every year, up to this, I have been contacted by one media outlet or another to explain where our butterflies are and why aren’t we seeing them. The interviewer typically prefaces his or her question with, “When I was a child I saw plenty of butterflies, so why am I seeing so few today?”

This year, 2023, is the first year that I was not asked this question. On the contrary, people commented happily about finding large populations adorning gardens and elsewhere this summer (but not in spring) and taking delight at seeing so many. Are they right, or is this just an impression formed by seeing butterflies when people have time off, like during August? Butterfly abundance peaks do not occur at the same time every year, so the poor weather in July is likely to have pushed peaks into August when the weather improved, and people had time to notice.

Let’s leave the butterfly year of 2023 to the annual report we publish under the Report heading. The National Biodiversity Data Centre (NBDC) has published the Irish Butterfly Monitoring Scheme Newsletter for 2022, the warmest year on record. What do the findings tell us?

Firstly, just a quick word on how the information is obtained. The Irish Butterfly Monitoring Scheme (IBMS) involves walking a fixed route (transect) on a weekly basis from 1st April to 30th September each year when weather conditions are favourable. The number of the different butterfly species seen along different sections of each transect are recorded. These records are the basic data upon which the analysis is based. The IBMS  tracks population and phenology (time of flight) trends in Irish butterflies, detecting the impacts of factors such as land use and climate change on the Irish butterfly population.

A reduced effort transect scheme, the Five Visit Monitoring Scheme (FVMS) helps to capture abundance. (Several Butterfly Conservation Ireland (BCI) members are involved in these important schemes and BCI runs its own recording scheme which provides data on distribution).

The results in the 2022 report do not make for happy reading.

The multi-species index which estimates the overall direction of change in the butterfly population using Ireland’s most common resident butterflies (15 species) shows that once again there was a moderate decline (-57%) in the number of butterflies flying in 2022 when compared with the baseline year of 2008 (the start of the monitoring scheme). Only the Holly Blue Celastrina argiolus showed an increase in the last 10 years (+149%), with all other species showing uncertain, stable or moderately declining trends.

It is important to note that the multi-species index is a useful index to show overall trends in population changes of common butterflies of the wider countryside. However, it does not generate sufficiently reliable data to track how the populations of our more localised or specialised butterfly species are changing. This is because there is currently not enough data being recorded for these species. To capture adequate information on these species additional species-specific schemes (like the Marsh Fritillary Monitoring Scheme) are needed.

The greatest declines during the period 2008-2022 are the Green-veined White (-81%), followed by Meadow Brown Maniola jurtina (-74%), Ringlet Aphantopus hyperantus (-72%), Large White Pieris brassicae (-71%), and Small Heath Coenonympha pamphilus (-68%). Aside from the Small Heath which has lost the status of being a wider countryside butterfly, all of these are, which suggests that there are significant problems in our environment. These are widespread butterflies, which suggests a widescale environmental crisis. Butterfly abundance will rise and fall naturally from year to year, but these declines span 14 years and are persistent.

Without great changes to farming methods, this is unlikely to change. The causes are not provided by the IBMS data but we can see that our farmed landscape is doused with herbicide, pesticide and synthetic fertilisers. These damage vegetation and butterflies; there is scientific evidence for this, as well as the more subjective, anecdotal support derived from personal experience.

A damp grass field near my home supported common countryside butterflies such as Orange-tip Anthocharis cardamines, Green-veined White Artogeia napi, Cryptic Wood White Leptidea juvernica and the Small Copper. Intensification began to occur. The vegetation was topped early one year to tackle rushes Juncus spp. This did not impact the butterflies but this spring herbicide was applied. It completely removed Common Sorrel Rumex acetosa (Small Copper foodplant), Cuckooflower Cardamines pratensis (Orange-tip and Green-veined White foodplant) and most if not all vetches especially Meadow Vetchling Lathyrus pratensis (Cryptic Wood White). I observed none of these species in this field in 2023. Even when herbicide is not used, nitrates play havoc with many butterflies.

While the EU Nitrates Directive has cut organic nitrates that can be applied to 220kg of nitrate per hectare, this figure is above the safe physiological tolerance level of the larvae of the six butterfly and moth species (Small Copper, Sooty Copper Lycaena tityrus, Speckled Wood Pararge aegeria, Small Heath, Blood Vein Timandra comae and Straw Dot Rivula sericealis) studied by Susanne Kurze and her colleagues.

The Kurze study showed declines in the survival of all six species when fed on sorrels and grass (depending on the moth or butterfly) when their plants were given between 150 and 300 kg N ha−1 year−1. At the higher rate, the sorrels died. The survival rate of the Small Copper was nearly 50% lower in the group fed on N300 than those fed on unfertilised plants. Grass-feeding species also suffered. The survival rate in the Small Heath and Speckled Wood declined by one-third under both nitrogen treatments compared with unfertilised plants.  Interestingly, some Speckled Wood larvae survived to pupation but the Small Heath larvae that died did not live longer than 45 days or reach pupation. The most sensitive species was the Straw Dot. Its survival rate declined by half between the control and the N150 treatment and about 80% between the control and the N300 treatment.

This study only scratches the surface. It did not deal with the impacts of these fertiliser concentrations on the overall vegetation in the wild, or the effect of more vigorous plant growth on soil and above-ground temperatures, all of which can also be expected to influence survival rates.

There is a great need for sustainable farming. Stocking rates are absurdly high, maintainable only by massive fertiliser inputs which poison wildlife, pollute water and add to global warming gases.

There is certainly no excuse for continuing to kill off our planet’s most beautiful animals. We waste about one-third of our food, so we are grossly over-producing and over-consuming. Our butterflies don’t need it and nor do we.

Key References:

Judge, M and Lysaght, L. (2023). The Irish Butterfly Monitoring Scheme Newsletter, Issue 15. National Biodiversity Data Centre.

Kurze, S., Heinken, T. & Fartmann, T. 2018, “Nitrogen enrichment in host plants increases the mortality of common Lepidoptera species”, Oecologia, vol. 188, no. 4, pp. 1227-1237.

All photographs © J. Harding

After being drenched and underwhelmed by daytime maxima of 13°C  during July and August our early September sunshine and warmth is a serious restorative. Today we are looking at 22°C to 26°C; yesterday temperatures climbed above 27°C in some areas; that’s more like it!

Met Eireann tells us that July 2023 was “very wet, cool and dull.”  In fact, it was the wettest July on record. The highest temperature recorded in July was on one day, July 7th, and was 24.1 °C in Fanad, County Donegal. While August had better weather, it was not a classic summer month. Described as “mild and changeable” the temperatures were above average nearly everywhere but so was rainfall. Poor Newport in County Mayo had 29 wet days during August!

This doesn’t look like our butterflies should have had a good year, given what our ‘summer’ weather was like, and if I include June this was much better (warmest June on record at most weather stations, with average rainfall). Athenry, County Galway and Shannon Airport, County Clare experienced 27 consecutive days with maximum air temperatures > 20.0 °C, ending on Saturday 24 June. Some of our summer flying butterflies had a spectacular year, with some very high abundance reported to Butterfly Conservation Ireland.

On September 3rd, for example, 246 Small Tortoiseshells were reported from Lullymore, and hundreds of Small Whites and hundreds of Small Tortoiseshells were seen on a wildlife-friendly farm near Maynooth. Red Admirals and Commas are booming too, Green-veined Whites, which love moist, damp habitats, are up, and so are Meadow Brown and Ringlet populations. Holly Blue seems to be thriving and spreading. Early in August, I counted 91 Brimstones just in a small area in Lullybeg; there must have been hundreds of this highly localised butterfly in the bogland in northwest Kildare.

So what can we expect this month? Top of the list is the Small Tortoiseshell, which is everywhere now, even in the Sutton area in Dublin, where the butterfly has gone into a second brood for the first time in many years, thanks probably for July’s bountiful rain and the boost to Stinging Nettles.

The highest numbers of the year are present now but this abundance will be brief. While they are busy feeding, they gain weight and their flight is considerably slower, especially in the cooler temperatures expected as September advances. It is risky to stay on the wing for too long, as dragonflies and birds are eager predators of butterflies. In the past few days, Small Tortoiseshells have entered buildings to look for a secluded nook to pass the winter in. In fact, some will find a spot, retain a topographical memory of its location, and fly out to resume feeding, safe in the knowledge that they know where they will hunker down. Experiments carried out in England show that the Small Tortoiseshell relies on its memory to relocate important sites.

They do not always choose well. A centrally heated building will awaken them in autumn, and deceive the butterfly into the idea that spring is here. Capture and release is not the advised approach; capture and relocation in a cool place is the best policy. A plastic lidded box lined with absorbent kitchen roll in the bottom of the fridge is a good place; no air holes are needed. Release them in March when a warm spell, predicted to last a few days, arrives.

By contrast with the Small Tortoiseshell boom, Peacocks on the wing are few in number. Most are in hibernation and will stay put despite the blandishments of high September temperatures and nectar. This poor Peacock looks the way we might feel after a bad day. Remarkably, this butterfly flew away, albeit awkwardly, after the photo was taken. Staying out late is risky, as pointed out earlier!

Another butterfly that passes the winter in the adult stage, the Brimstone, is similarly out there in greatly reduced abundance. Most of them are concealed in evergreen foliage, blending with their leaflike wings to aid blending. We will see a few still feeding, and these are wisely very close to over-wintering cover.

Green-veined White butterflies really suffer from droughts, but not this year. Here is a male on Devil’s-bit Scabious, his forewings packed with citral (C10H16O), a pheromone used to seduce a female. It is a powerful, sweet fragrance, easily detected by a human, so it must be an all-enveloping experience for a female Green-veined White. This butterfly is still breeding and the species will pass the winter as a caterpillar.

And now for something different! The next two butterflies are migrants. Unlike our resident butterflies, these two are not cold-adapted species. Unlike our resident natives, these do not have a rest phase in their life cycle and are continuously brooded, which means they breed and grow throughout the year. In more technical language, they do not undergo a diapause phase. If a butterfly cannot delay breeding, it requires the correct conditions to reproduce throughout the year. These conditions are not currently available in most of northern Europe, so an escape strategy must be applied. Migration is a way to avoid the onset of unsuitable conditions. In spring and summer, the heat in North Africa and parts of Southern Europe drives some migrants north to find the conditions needed.

The Red Admiral is our most regular migrant butterfly. It occurs in Ireland from about March to November and they leave during the autumn months. When the herbaceous flowers are gone, it uses ivy nectar, sap runs and overripe fruit for sustenance. There are still Red Admiral larvae on nettles so we will see the adults for some weeks yet.

The lovely Clouded Yellow is a visitor too, but in smaller numbers and often later in the year, especially during September and October. In some years a mass arrival followed by breeding occurs. In these years, they arrive earlier, usually from April onward.

In years when they arrive later, the Clouded Yellow does attempt to breed, but it is likely that the attempts fail as the temperatures drop. But the butterfly is a delight to see whenever it appears. This female was seen in Lullymore by Pat Wyse and Fionnuala Parnell, enjoy!

Back to our resident butterflies, the Comma is beginning to hatch its second generation which flies during autumn. This makes it unique among our butterflies. We will say more about the Comma in our October post, but keep a close eye on ripe blackberries and ivy in the coming weeks.

The heatwave during the first week in September has coaxed migrants from southern Europe to journey north. This Vestal is one of four to visit a garden in County Meath on 7th September. The colour of this moth is strongly influenced by the temperature experienced by the pupa with bright specimens like this one the result of hotter conditions, suggesting that this one is from the Mediterranean area of Europe or North Africa. It is mainly a nocturnal moth but can be found on grass stalks during the day.

All photos by J. Harding except Clouded Yellow P. Wyse.

 

 

 

 

 

 

There is a drop in the number of moth species present in the garden in August compared with June and July but there is still variety in my moth trap, with some intriguing species. Here is a selection of moths that fly during August.

The Magpie is a striking moth that flies at night but occasionally during the day too. I recently watched a female flying on a sunny afternoon, laying eggs on Berberis thunbergii atropurpurea, a purple-leaved garden plant used for hedging or as an individual specimen. It breeds on a wide range of native plants Common Hazel, Common Hawthorn, Common Spindle, Heather (in Scotland and presumably here). It is capable of long flights, and famously Orkney and Shetland were colonized by it in the last few years. It appears to enjoy good abundance in Ireland but it has declined in England and Wales.

The Chinese Character might be better called the Bird Dropping moth for its resemblance to a bird dropping. This breeder on Crab Apple, Common Blackthorn, Common Hawthorn, Rowan, and other trees appears to be avoided by birds. Certainly, my Robin, who loves seeing my moth trap light up, shows no interest in this enigmatic moth. This moth is double-brooded.

The Scalloped Oak is also nocturnal and while it breeds on oak, it uses a wide range of trees as well as Honeysuckle, Bilberry and Heather. Given such a wide range of foodplants, it occurs in a range of habitats, such as woodland, hedges, gardens, parks, and bogs. It has one generation every year.

The Gold Spot is double-brooded, nocturnal, and occasionally day-flying when the day is muggy and overcast. It likes wet habitats, as it breeds on sedges, Yellow Iris, Branched Bur-reed and Water-plantain. It occurs in gardens that hold ponds with marsh and marginal vegetation.

The Pebble Prominent is generally common, breeds on willows and is double-brooded. In some years I get only one or two, but this year has been better, with five found last Wednesday.

The Bee moth is a very interesting micro-moth that breeds on the nests of a range of wasp and bee species. Their yellow caterpillars protect themselves from their hosts by spinning a tough silk case, while they feed on the comb, honey, stored food, and even meconium (fecal matter). They can destroy nests and are considered a pest by beekeepers. Both sexes use sex pheromones during courtship and males sing to females by vibrating their abdominal plates. A courtship dance by both sexes occurs before mating. While this appears to be a destructive species, it should be noted that all species have their enemies, and it is rarely if ever the case that one species destroys its host, under circumstances of a functional ecosystem.

The Canary-shouldered Thorn is very well-named! It breeds on Downy and Silver Birch, Alder, limes, elms, Goat Willow, and Hornbeam. It is strictly nocturnal and flies in just one generation a year, from July to mid-October.  It spends the daylight within trees, concealed on the underside of leaves.

As you can see, these moths breed mostly on native plants or, in the case of the Bee Moth feed on hosts that use native plants. By making native trees, shrubs, and flowers the key architecture of your garden, you will be making homes for our native moths and all the species that depend on moths for their survival. The Russian revolutionary Lenin is quoted as having said, “Everything is connected to everything else.” Without the elements needed, our ecosystems would collapse. Moths are excellent indicators of ecosystem functioning because they play such key roles mainly by providing food, pollination, and plant growth regulation. We have c. 1567 moth species in Ireland, so they are a significant proportion of our invertebrate population. Together with butterflies, the order Lepidoptera makes up about 9% of all life forms on the planet. We cannot do without them.

 

 

Just one pleasure that you as a nature lover can enjoy is simply strolling through your favourite haunt and seeing what’s there. Like me, you might not recognise every creature encountered but the identification challenge adds a layer of interest and purpose to your ramble. The pleasure of exploration and discovery might prompt further inquiry, more learning, and a greater understanding of the complexity of our wonderful world. In this post, I will show you some of the photos I took on a recent ramble, explain a little about each species, and try to give an impression, however superficial, of how these characters fit together in their world, and ours, and how this can change over time.

First up is a Comma butterfly. Intriguingly, this butterfly exists in two forms. You can tell something about the life the caterpillar led by looking at the adult. If when the caterpillar when developing, it was feeding on nettles with a high nitrogen content, and receiving 18 or more hours of sunlight, or was developing when daylight hours were increasing, it is likely that a light-form adult would emerge in July/August. This light-coloured Comma breeds soon after emerging. If the day length was marginal, and the larva fed on nutritious leaves in warm conditions, a light Comma is also likelier.

A dark Comma results when the caterpillar fed when the day length was declining, or it was cool and the plant was not especially nutritious. The dark Comma will rarely breed until the following spring. It behaves like the Peacock butterfly that hatches in summer, feeds, and enters hibernation in cool, dark, dry situations in woodland. A much darker underside makes it far harder for birds to find than light-coloured Commas.

Then I sighted a female Brimstone, resting. Like the Peacocks, which were found nearby, it was not very active and was not looking to fly into the path of a male. Neither of these two will mate until next year. Both pass the winter as adult butterflies. The brimstone among leaves that match its outline and vein markings, the Peacock in dark places that match its black underside.

A large wasp-like creature busily foraging on a Wild Angelica flower caught my eye next. This is an ichneumon wasp, one of many similar-looking wasp species. These wasps make a living from moth caterpillars and other insect groups and arachnids (spiders) by parasitising them.  The noctuid moth family is often used as hosts for these wasps, which inject eggs into the caterpillars, or lay near them, develop inside the caterpillar before emerging from the dead or dying caterpillar and pupating. Ghoulish though it sounds, the wasps regulate population sizes and, indirectly, vegetation growth, preventing mass population booms that threaten to self-annihilate by eating all their food.

Another wasp-like creature was on the Wild Angelica, but this one is not a wasp, but a fly. The Two-banded Wasp Hoverfly is well-named. A nectar-feeder as an adult, the larva feeds on aphids. It is quite a striking-looking creature but is usually seen singly.

A much quieter creature next took my eye. This was a Tortoise Shield Bug, a plant feeder. Another one was on bramble, the Green Shield Bug, another plant eater. If disturbed it often emits a marzipan smell, which is quite cloying, but harmless. If cutting your meadow back in late summer or autumn you might notice it! It spends the winter as an adult and breeds the following spring.

The pondside scrub vegetation yielded two male Beautiful Demoiselles, which were displaying, hoping to catch a girl’s eye. They were skittish, landing only briefly so I was delighted to get a photograph. It needs fast-flowing, clean, pebble-or sandy-bottomed streams. The pond is fed by a clean stream, with a marl bottom, which obviously keeps it happy.

The skittishness of males might be related to their need to protect an egg-laying site from other males. His female must lay her eggs there under his protective gaze. If not, an interloper might mate with ‘his’ female and replace his sperm. It is a tough life being a male Beautiful Demoiselle!

A sighting that surprised me was a male Holly Blue. It is a less frequent butterfly in rural locations, preferring suburban and urban gardens where there are heat traps, and masses of holly and ivy for breeding. The butterfly uses many other plants for breeding, but these are the main choices, in spring and summer/autumn respectively. The one I saw was feeding on Common Heather, slate blue among pink evoking delicate beauty.

Another surprise is the number of very fresh Meadow Browns. This species emergence times are quite uneven across the country, even with an individual county. Thus, 29 Kilometres away on the Kildare/Meath border, the Meadow Brown is now scarce, with a few faded, geriatric specimens flapping weakly in sheltered places. In Lullybeg it remains abundant, with several newly hatched individuals like the one pictured seen on my early August ramble.

When I arrived home, I checked some roadside Stinging Nettles. Under a large leaf about halfway down the stem of a nettle was a Comma caterpillar, in its second instar. This caterpillar is developing under rapidly declining daylight, meaning that it is guaranteed to be a dark Comma. This will, should it survive, be flying in September, and will join its uncle, pictured at the start of this article, in hibernation. Therefore, our spring Comma population, all (or nearly all?) dark form Comma butterflies, consists of two generations from the previous year, ones that hatched from their pupae in July/August and the second brood adults hatching in September/October.

The ramble showed how interactions are taking place between different aspects of the biodiversity encountered. The wasp, hoverfly and butterflies fed from flowers, pollinating them to produce seeds for plant reproduction and seed-eating animals. The butterfly larvae eat plants and are in turn eaten by parasites and other predators, which themselves are used in the food web. Species regulate and are regulated by other members of their community. This creates a balance, so no member of the community dominates at the expense of others, over time.

There are deeper interactions than can be described here, but one interesting study that might indicate the effects of climate warming on some of our butterflies and their community has been conducted in Sweden. The Swedish study looked at four nettle-feeding butterflies and at how climate change has influenced their populations, in the context of the arrival of the nettle-feeding Map Butterfly, which is tracking climate change by extending its European range northward, just like the nettle-feeding Comma.

The study, Rewiring of interactions in a changing environment: nettle-feeding butterflies and their parasitoids (citation below) looked at the interactions between four nettle-feeding butterflies and their shared parasitoids in Sweden and the impact of the newly arrived Map butterfly, via its parasitoids, on three long-term residents, the Small Tortoiseshell, Peacock and Red Admiral (the Red Admiral is described by the study as a resident, but it is a migrant to Sweden, breeding there annually).

They collected 6777 wild larvae of the four species over two years. Of the 6777 collected larvae, 1508 were parasitised (22%) and produced parasitoids from three families: Tachinidae (Diptera), Ichneumonidae (Hymenoptera) and Braconidae (Hymenoptera). They identified 11 species: the tachinids (flies) Pelatachina tibialis, Sturmia bella, Phryxe vulgaris, Phryxe nemea, Pales pavida and Blondelia nigripes, the ichneumonids (wasps) Phobocampe confusa, Thyrateles haereticus and Thyrateles cam­elinus, and the braconids (wasps) Microgaster subcompleta and Cotesia vanessae. Some of these parasitoids have not been recorded here; those that occur in Ireland are in bold. Overall, 76.7% of the parasitised larvae were parasitised by either  Pelatachina tibialis (34.6%), Phobocampe confusa (28.5%) or Sturmia bella (13.6%). All four butterflies were attacked by these three parasitoids, except for the Map butterfly which was not infected by P. confusa.  The Red Admiral was attacked by most parasitoid species, including representatives of all three families. Unknown causes were also responsible for caterpillar mortality.

The most heavily parasitised butterfly was the Small Tortoiseshell, followed by the Peacock. The Red Admiral was third and the Map butterfly was least impacted. Parasitism rate increased in the Peacock when its larvae were found with the larvae of the Map butterfly and Red Admiral but decreased when it co-occurred with the Small Tortoiseshell. For its part, parasitism increased in the Small Tortoiseshell when its larvae occurred with those of the Peacock. They also observed that the parasitism rate in the Peacock increased with the number of co-occurring butterfly species. Looking at parasites that infect both the Map and the native butterflies (Peacock, Small Tortoiseshell and Red Admiral) they found that Small Tortoiseshell had higher levels of infection when it co-occurred with the Map.

It was also discovered that in the Swedish sites where the Map was known for the longest, the Small Tortoiseshell and Peacock had higher rates of parasitism. The low rates of parasitism in the Map and Red Admiral are discussed but no definite conclusion is made. However, one strong possibility for the low infection rate in the Map is that because the Map is a recent colonist in Sweden, it may have escaped its parasitoids initially, and is only beginning to recruit parasitoids in the last c.10 years. In areas where the Map had only recently arrived, infection rates were lower for the Small Tortoiseshell and Peacock.

The Map might be causing higher infection rates by shared parasitoids by providing a host for the parasitoids when the larvae of the Small Tortoiseshell and Peacock are scarce. The three species’ caterpillars overlap in their occurrence, but there are phenological differences (differences in the timing of the appearance of the caterpillars).

Populations of the Small Tortoiseshell are bivoltine (two generations) in Sweden. Its larvae are recorded from early May to the end of August with the first generation being found from early May and the second gen­eration from late June. The Peacock is univoltine (one generation) in Sweden with larvae observed from late May to early August (like in Ireland). The Map is a bivoltine species but in contrast to the Peacock and Small Tortoiseshell, which overwinter as adults, the Map hibernates in the pupal stage. Larvae from the first generation are found in the field in June; larvae from the second generation are found from the end of July to early September. The Red Admiral is a migratory but­terfly in Sweden and its population depends on the migra­tory influx from the areas where the species is resident. It is univoltine in Sweden with larvae observed in the field from May to early September.

All species are distributed across Sweden, except for the Map which is currently limited to the southern half of the country.

Therefore, there are times in the year when Map larvae are plentiful but those of the Peacock and Small Tortoiseshell are less numerous. Phenological differences in the parasitoids between hosts might also mean the Map is assisting increased infection rates in its butterfly relatives. If correct, the Map is reducing the competition for its food (nettles) during its establishment phase, but if the Map recruits more parasitoids, as the study indicates is likely, a balance between the four butterflies might be struck.

However, the Swedish study did not look at several other potentially relevant factors, including the parasitoids that the Map may have introduced to the other three butterflies, only looking at shared parasitoids, and looked at larval parasitoids, not egg or pupal ones. Thus, a warming climate that causes a butterfly to extend its range may bring challenges for established natives. We simply do not know the extent of these. The study does not point out that all four of the nettle-feeding butterflies occur further south in Europe.

While I love the Comma butterfly and rejoice in its colonising zeal, are our established natives being put under increased survival pressure? In Ireland, the Comma has been found breeding mainly on the Stinging Nettle. The recent decline in the Peacock population in northwest Kildare coincides with the establishment of the Comma in the area, but this abundance decline might be coincidental and related to many other factors, such as weather conditions, changes in the habitat, unshared parasitoids, changes in the behaviour and population of the parasitoids, viruses, and bacterial infections unrelated to the Comma’s arrival.

None of this is known. But it certainly adds intrigue.

Our Small Tortoiseshell, Peacock, and Red Admiral populations are very important in our landscape because they are common, widespread, and often abundant. The impact on the wider community is all the greater if they decline because these abundant animals connect with a large range of species.

That happy, carefree ramble reminds us that we have so much to learn. Keep watching our butterflies, our canary in the coal mine.

Key Reference

Audusseau, H., Ryrholm, N., Stefanescu, C., Tharel, S., Jansson, C., Champeaux, L., Shaw, M.R., Raper, C., Lewis, O.T., Janz, N. & Schmucki, R. 2021, “Rewiring of interactions in a changing environment: nettle‐feeding butterflies and their parasitoids”, Oikos, vol. 130, no. 4, pp. 624-636.

 

 

 

August is a great butterfly month, but listening to the rain splattering above my head as I write I should probably append the adverb ‘allegedly’. The weather forecast for the first week in August is for dull, wet and at times windy weather, not the right conditions for flying insects. Our butterflies are accustomed to our wet, erratic weather, and even brief sunshine is capitalized on, with often impressive abundance as butterflies have emerged from pupae and are waiting to fly.

An impression of abundance is often noted on the first sunny day following days of rain, with exciting numbers evident. This population boom should not be confused with an increasing trend. Typically, butterfly pupae hatch over weeks, but if the weather is unfavourable, several days’ hatched butterflies will wait to fly together on the first good weather day, rather than fly in apparently reduced abundance over several days with good weather conditions. Similarly, pupae that have been ready to hatch for some days may delay hatching until a sunny day arrives.

Assuming the sun shines in our wet and wild countryside, what can we expect to see?

This depends not just on the habitat but where in Ireland it is you are looking for butterflies. The Meadow Brown, on its ‘last legs’ in many areas in the east, is just beginning to emerge in abundance in many areas of the west and northwest during August.

Huge abundance can be encountered on coastal grasslands in Donegal and Clare during August, fresh and eager to mate, while their eastern cousins are faded or dead. By contrast, the Small Copper can be seen in suitable habitats throughout Ireland during August.

A butterfly with a restricted Irish distribution that flew in spring should be around in August. The Wood White, a Burren and western limestone butterfly will be flying in its habitats. This second flight is a partial generation. The first flight, which occurs mainly during spring comprises all the over-wintered pupae.

The last Irish butterfly to emerge is the Brown Hairstreak. Our largest and rarest hairstreak exists in the Burren (Clare and Galway) and a small number of areas outside the Burren, such as west Tipperary, Ennis, near Lee’s Road, around Lough Corrib, Lough Mask (both Galway) and possibly Lough Carra (Mayo). This obscure but beautiful species is associated with wilder, bushy places typically (but not always) on exposed carboniferous limestone. It peaks in abundance during August and has been seen as late as October. Look out for it on bramble flowers, and on Creeping Thistle near scrub.

Another butterfly that is restricted in its Irish distribution but more widely distributed than the Wood White and Brown Hairstreak is the Brimstone. The new generation flies from July to September or even early October but its peak flight is in August. The Brimstone joins the Peacock and Small Tortoiseshell to gorge on nectar in flower-rich areas close to woodland before all three species go into hibernation. Bramble, Common Knapweed, Rough Hawkbit and Devil’s-bit Scabious are favoured flowers for all three.

A lovely, small (19-20 mm wingspan) intensely coloured day-flying moth to look for on wild grassland is the Small Purple-barred. Ranked ‘Near Threatened’ on our Macro-moth Red List 2016. This moth breeds on Common Milkwort, which need semi-natural grassland untainted by agricultural chemicals. A common day-flying moth during August is the Shaded Broad-bar, a brown/buff grassland moth with a dark brown crosswise bar on its forewings.

On limestone grassland, chiefly in the Burren, the Straw Belle may be encountered; it is a nocturnal species that is easily roused in daylight. Straw-coloured and brown-freckled with a brown diagonal bar on the forewing, this species is especially common on short Burren grassland. A moth confined to the Burren, the Burren Green, ranked ‘Near Threatened’ is abundant in the Burren during August. This moth is mainly nocturnal, but it will fly in daylight on muggy, over-cast days when it feeds on Common Knapweed. This moth is not found outside the Burren in Britain and Ireland. It breeds on Blue Moor-grass.

These are just a few of our August flyers. We will leave you to discover others, but remember to let us know what you see, according to the record submission procedures here:

https://butterflyconservation.ie/wp/records/

All photographs are ©J.Harding.

Butterfly Conservation Ireland’s reserve at Lullybeg is monitored using the transect system. This uses a fixed route to count butterflies on the reserve between April 1^st and September 30^th each year. The count includes all butterflies seen 2.5 metres to the left and right of the walker, 5 metres ahead of the walker and 5 metres above. The results of these counts are sent to the National Biodiversity Data Centre. In addition, counts are made on the reserve away from the transect.

Having systematic butterfly count data for the site since 2011 means trends in species and abundance can be tracked which means we can check the effects of changes in management, successional changes in the habitats, weather conditions and even climate on butterfly populations.

Here we give an indication of the reserve’s performance at the halfway stage in 2023.

The reserve has some species whose conservation is a concern nationally, and these are especially important monitoring subjects. The Small Heath, rated Near Threatened, has dramatically declined on the reserve. From a high of 231 individual Small Heaths in 2013, a slight drop to 229 in 2014, the trend has been of steady falls since. The years 2015, 2016, 2017, 2018, 2019, 2020, 2021 and 2022 saw 131, 62, 61, 63, 57, 44, 74 and 35 Small Heaths respectively.

This year the Small Heath count is 54, a healthy increase on 2022’s poor result but still much lower than its peak in 2013 and 2014. We are investigating the habitat conditions it likes on the reserve to inform decisions about how to manage these areas and how these conditions compatibly align with the ecological requirements of other important butterflies. This is quite a challenge in a relatively small reserve.

One conclusion is that the Small Heath dislikes heavy grazing. This is clear from the nearby reserve at Lullymore, where it has been eliminated by grazing designed to cater for the Marsh Fritillary, where donkeys were introduced to graze on Purple Moor-grass to prevent it from overwhelming the Marsh Fritillary foodplant. The Small Heath likes fescue grasses, and the growth form it especially likes is tall, shaggy, dense tussocks containing plenty of dead grass blades. Unfortunately, grazing livestock love this grass, and attack this before tackling the rougher species.

The Small Heath also likes smaller, sparser Red Fescue growing among sparsely vegetated ground, but semi-bare terrain is quite temporary on vegetated cutover peatlands. Thus, successional change is a threat, unless the fescues grow into dense tussocks needed, but this only happens if grazing does not occur or is very sporadic. The ground can be disturbed by cattle to create bare patches, but will Red Fescue colonise these quickly before more robust grasses assume control?

The timing of grazing and topping of vegetation and the severity of topping are also important. Late autumn or early winter grazing and topping is probably best for the butterfly. These were used in 2022 and a population rebound was observed, but some of this recovery was in areas not grazed and not topped.

A priority butterfly that is doing well on the reserve is the Marsh Fritillary. A mere 15 were counted in 2011, followed by 19 in 2012, 41 in 2013, 92 in 2014, just 32 in 2015, 14 in 2016, 17 in 2017, 31 in 2018. After this numbers increased.

Totals of 287 and 207 in 2021 and 2022 respectively show this recovery. This spring and summer 246 Marsh Fritillaries were counted, great news that shows the management is working well for this threatened species. The control of scrub and light grazing is key to this success.

Another threatened butterfly, the Dark Green Fritillary is still on the wing, so the picture is unclear at this point. Only two males have been recorded so far. There are plenty of Common Dog-violet plants in parts of the reserve but the sward around the highest violet populations is probably too low for this species.

The Silver-washed Fritillary has shown lower numbers in recent years. In 2020, 2021 and 2022 the figures were 9, 6 and 8 respectively. Up to mid-July 2023, 16 Silver-washed Fritillaries have been seen and this number will increase, so that is very good news.

So far in 2023, 1237 Ringlets have been counted (only 636 in 2022), and 168 Meadow Browns (204 in 2022). These two are still flying, so the totals will rise.

Twenty-two Dingy Skippers were found this year; its flight period is over for 2023. In the four years 2019-2022, the numbers seen were 10, 10, 47 and 31. The trend will be closely monitored next spring.

It is wonderful to see increases in the Small Heath, Marsh Fritillary, Silver-washed Fritillary and Ringlet, and an expected rise in Meadow Brown numbers. Without your help, none of this would happen.

These figures show what is possible elsewhere in our countryside if managed properly. Land managers and conservationists take note!

Photographs copyright J. Harding.