Butterfly Conservation Ireland

The UK is one of the world’s most nature-depleted countries – in the bottom 10% globally and last among the G7 group of nations, new data shows. It has an average of about half its biodiversity left (53%), far below the global average of 75%, a study has found.  A figure of 90% is considered the “safe limit” to prevent the world from tipping into an “ecological meltdown”, according to researchers. The assessment was released ahead of a key UN biodiversity conference. (https://www.bbc.com/news/science-environment-58859105)

Here I will take the UK’s butterflies to see how depleted her species list has become. The British race of the Large Copper butterfly was lost forever in the 1860s, a victim of habitat loss when its wetlands were drained. By the start of the twentieth century, Britain held 62 butterflies which comprised resident breeding species and the regular migrants, which also breed in Britain. Some areas were so rich in butterflies as to be meccas for Victorian and Edwardian collectors. The New Forest, in Hampshire, was a butterfly paradise. For over a century, gentlemen, usually from the upper and professional classes, flocked to the forest’s boarding houses and inns for a collecting holiday.  Treasured specimens and livestock were traded, and an unusual specimen could pay for the entire holiday.

Local people were gainfully employed in late spring and in July especially, selling insects, acting as guides, providing accommodation, food, drink and transport (pony hire).  In some years butterflies were remarkably abundant.  Sydney Castle Russell describes a visit during the hot summer of 1892:

As I walked slowly along, butterflies alarmed by my approach arose in immense numbers to take refuge in the trees above. They were so thick that I could hardly see ahead and indeed they resembled a fall of brown leaves.

The summer of 1893 was even better.  One recorder reported mass abundance:

...the said bed of the stream for more than a mile was literally crowded with butterflies, the bulk of them being adippe (High Brown Fritillary, now extinct there), paphia (Silver-washed Fritillary) and sibylla (White Admiral). 

The great figure of British butterflies in the late nineteenth and early twentieth century, FW Frowhawk (1861-1946) first visited the forest in July 1888. He was stunned by the abundance he witnessed:

I shall never forget the impression it made…Butterflies were in profusion. A. paphia (Silver-washed Fritillary) were in hordes, the variety valezina was met every few yards, as were A. adippe (High Brown Fritillary). L. camilla (White Admiral) were sailing about everywhere…N. polychloros (Large Tortoiseshell) was of frequent occurrence.

Butterfly paradises also existed on the rolling chalk grasslands of southern England, where collectors sought unusual varieties of the Chalkhill Blue or the rarer prize, the Large Blue. The time of plenty and carefree innocence was not to last. World War I killed many butterfly collectors, whose activities had little or no effect on butterfly abundance. The decisive blows were inflicted by modern silviculture, which removed native broadleaved trees for non-native, fast-growing conifers. Coppicing virtually ended in remaining native woods, darkening the woodland floor, shading out foodplants. Chalk grassland was ploughed up for intensive agriculture, with grasslands comprising Rye-grass and White Clover and crops replacing precious species-rich butterfly habitats.

Changes in the ways remaining chalk and wet grassland were managed also took their toll.

The Mazarine Blue, still widespread and common in Europe, went extinct in 1903. The Black-veined White followed in 1922. The Large Tortoiseshell, still found in Northern France and most of Europe, vanished in the late 1940s, the Chequered Skipper became extinct in England in 1976, the Large Blue followed soon after, in 1979. The Heath Fritillary almost vanished in the 1980s and is now confined to ground comprising c.1km square. The High Brown Fritillary is in very serious trouble, despite some efforts to conserve it,  and this large fritillary may well be lost. The Pearl-bordered Fritillary might yet be lost.

Consider the views of Professor Jeremy Thomas on the likely fate of the High Brown Fritillary and Duke of Burgundy:

The most notable casualties (of the deteriorating habitats in woodland) are the Duke of Burgundy, and the High Brown and Pearl-bordered Fritillaries. Despite some local conservation successes, it is a moot point whether the High Brown Fritillary or the Duke of Burgundy is the next most probable butterfly to become extinct in the British Isles (Thomas and Lewington, 2014).

Most of the attempts to restore extinct species have failed. One species, the Large Blue, has been reintroduced but from Swedish stock. The British race is extinct. An attempt is currently underway to return the Chequered Skipper to a single woodland site in England but the butterflies being used are from Belgium.

Many other species, while not endangered, have retreated. Data from the UK that covers the period 1976-2014* shows a worrying picture. A range of species including the Dingy Skipper, Grizzled Skipper, Wall Brown, and Small Heath have declined. The local extinction of Wall Brown colonies across a huge tract of southern Britain is reflected in a 77% decrease in occurrence (distribution) and an 87% decrease in abundance (population size) 1976-2015. Only six other butterfly species show a greater long-term decrease in occurrence and only three have more severe population declines in the UK.

Regarding the Small Heath, the new fine-scale assessment of distribution data (this species appears to be holding its own if one only considers its presence in 10 km squares) shows that the Small Heath has decreased by 57% since 1976, while its abundance on monitored sites has also more than halved over the same period. To put this into context, the Small Heath has fared worse than the Grizzled Skipper, Small Blue, Northern Brown Argus or White Admiral, despite being much more widespread than any of them (Small Heath is the 11th most widespread UK species based on occupied 10km squares in the 2010-2014 BNM survey).

Overall, the UK Butterfly Monitoring Scheme (which monitors population abundance annually on sites) results show that 57% of individual species had decreased in abundance since 1976, although not all these trends are statistically significant. Among the 33 species with statistically significant long-term trends, 61% decreased over the period.

Analysis of the Butterflies for the New Millennium recording scheme data reveals that 70% of species decreased in occurrence over the period 1976-2014.

The destruction and deterioration of habitats because of land-use change (e.g., intensification of agriculture, changing woodland management) are still considered the prime causes of long-term decline among habitat specialist butterflies (species restricted to specific habitat types) in the UK. However, the factors responsible for the decreases of wider countryside species are not well understood.

The figures for the UK include Northern Ireland, where the Brimstone became extinct in the 1980s, where the Wall Brown may be extinct, with just a single individual recorded during the years 2015-2021. The Dingy Skipper and Small Blue are highly restricted in their distribution in Northern Ireland.

How healthy are butterfly populations in the Republic of Ireland?  We probably lost one species, the Small Mountain Ringlet, late in the nineteenth or early in the twentieth century. We have not lost a butterfly species in the Republic of Ireland since the loss of the Small Mountain Ringlet if that species really did exist in our western mountains. Considerable doubt exists concerning this species past occurrence in Ireland.

There is much less data available for the Republic of Ireland’s butterfly populations, underlining the poorly funded state of voluntary conservation bodies and official disinterest.  There are currently 35 species present in the Republic of Ireland, including three regular migrants. However, the Irish Butterfly Monitoring Scheme (this involves butterfly transects, which monitors annual population abundance on sites) run by the National Biodiversity Centre and the casual recording schemes (records from various parts of the island, not from transect counts) administered by the National Biodiversity Data Centre, the Northern Ireland Environment Agency,  the Northern Ireland branch of Butterfly Conservation UK and Butterfly Conservation Ireland are accumulating this data, to be published in The Atlas of Ireland’s Butterflies 2017-2021.

Indications of the status of some species are available. Preliminary findings published in 2020** indicate a change during 2008-2019 in the Small Heath of -51%. The small number of monitored sites for the other species we really need data about means we simply do not know the status of our scarcer species as regards abundance, which is the data captured by the Irish Butterfly Monitoring Scheme.

While individual observations cannot be applied to make a confident assessment of the conservation status of our butterflies, observations in the form of casual records submitted to the databases of Butterfly Conservation Ireland and the National Biodiversity Centre suggest that some species are in strong decline. The Wall Brown is certainly in trouble, declining in occurrence and very likely in abundance. The Gatekeeper/Hedge Brown appears to have a shrinking distribution, and this appears to be the case for the Grayling which seems missing from some areas of the coast it was known from in the past. The Large Heath is quietly sliding into oblivion, alongside the Curlew, as its bogs are destroyed. Another species that relies strongly on bogs, the Green Hairstreak, is also being impacted by the mass destruction of bogs, wet heaths and other wet places.

However, while it must be admitted that while we simply lack comprehensive, scientifically robust, confirmatory data of butterfly abundance decline for most of our scarcer species, we can see the habitats used by butterflies being damaged and destroyed. Across vast areas of our landscapes, our semi-natural grasslands, to take just one example of habitat, are so modified by drainage, chemical inputs, ploughing and re-seeding as to squeeze butterflies and many species else to the few edges and corners that remain, if any suitable habitat remains, leaving sink populations that eventually disappear.

Where agricultural intensification occurs without chemical inputs, such as clearing the land of rock or rock outcrops, importing topsoil or increasing stocking rates of cattle and sheep, the vegetation also changes, making the habitats less or even unsuitable for butterflies. In many areas where habitat is not destroyed, it is neglected and changes so it loses much of its biodiversity. Neglect takes many forms, including allowing invasive, non-native plants to encroach, land abandonment, which sees traditional biodiversity-friendly management practices cease, which changes the character of the vegetation resulting in a decline in the number of species over time.  The negative impacts of these changes can be experienced on adjoining land, even where the adjacent habitats have not been directly altered.

Less visible forces are likely to be exerted pressure on our butterflies. Pollution such as atmospheric nitrogen deposition and rising Carbon Dioxide levels are changing soils, vegetation, and grassland temperatures. The impact of these influences on our butterfly and moth populations will, one hopes, become clear over time. If the findings of European research pertaining to these factors apply here, we will need to consider pollution as an influence on the fate of our butterflies.

Of course, butterflies don’t exist independently of their habitats or other species. Sites poor for butterflies and moths are generally low in biodiversity. In that sense, butterflies are a great indicator of the biological health of our country. Cherish butterflies, and you cherish biodiversity. Areas healthy for butterflies are healthy for other wildlife, and for human life.

A place without butterflies is a bad place. A place without nectar, bees, grasshoppers, orchids, birds, clean soil, clean water, clean air. If a place lacks butterflies, it lacks so much more.  Turning our backs on butterflies is turning our backs on ourselves.

Perhaps we should think about that?

*Fox, R., Brereton, T.M., Asher, J., August, T.A., Botham, M.S., Bourn, N.A.D., Cruickshanks, K.L., Bulman, C.R., Ellis, S., Harrower, C.A., Middlebrook, I., Noble, D.G., Powney, G.D., Randle, Z., Warren, M.S. & Roy, D.B. (2015). The State of the UK’s Butterflies 2015. Butterfly Conservation and the Centre for Ecology & Hydrology, Wareham, Dorset.

** Judge, M and Lysaght, L. (2021) ‘Butterfly populations still declining’, The Irish Butterfly Monitoring Scheme Newsletter, Issue 13.

October is the second month of autumn and can be a gentle month weatherwise, as it is this year.

Butterfly numbers fall off the cliff in October, leaving us bereft. It is a disquieting and bemusing experience especially when the weather is suitable for butterfly activity and nectar remains available.

While this experience of butterfly scarcity is general across Ireland, it is not universal here. In some southerly locations, butterflies remain active. Red Admiral and Painted Lady butterflies often gather in force in mild southerly coastal areas, feeding on remaining wild and garden flowers before migrating south or, in the case of a few Red Admirals, attempting to breed. Speckled Woods persist longer in south Cork, continuing to station themselves along hedges and grassy hedged lanes, feeding on late bramble, Common Ivy, and ripe fruit. The occasional Small and Large White will be laying eggs on wild and domestic brassicas and the Small Copper will be showing up in warm, sheltered nooks as a few third brood individuals make an attempt at late breeding. There might be a surprise Common Blue and Holly Blue, for the observer in the right place.

A not irregular sight along the south coast during October is the Clouded Yellow butterfly, a strong migrant from warmer regions in southern Europe. Why this butterfly turns up here so late in the butterfly year is unknown, especially as its foodplants have, by now, recovered from the drought experienced in southern Europe in most years. The butterfly can look misplaced in October, its deep mustard yellow an optimistic foil in a land of fading colours and dimming light. Ecologically, it is hard to understand why it migrates here so late because its larval foodplants are in sharp decline and temperatures are falling, factors that militate against successful breeding. This enigma does not obscure the thrill this sight gives the discoverer-the Clouded Yellow is one of our loveliest and most powerful butterflies.

Although butterfly numbers crash in October, moth abundance holds up impressively. There are fewer species in flight, but abundance is still quite high because some species that produce high numbers are autumn flyers. Examples include Beaded Chestnut, Setaceous Hebrew Character and Blair’s Shoulder-knot. These are busy mating and laying eggs and are a vital resource for pre-hibernation bats.

Most autumnal moths are suitably cryptic, matching the more muted hues of the season. While the pretty Pink-barred Sallow pictured next appears conspicuous, it blends nicely with the foliage of trees at this time of year, melting into the crimson and gold mottling found on the leaves of willow and other trees.

The following moths, the Beaded Chestnut, Yellow-line Quaker and Red-line Quaker are beautifully adapted to autumnal colouring. Like butterflies, moths often settle on similar-coloured surfaces to avoid detection by birds and mammals.  Anyone who has trapped moths using a light trap knows how eagerly moths are sought by birds, particularly by Robins, Wrens and Magpies.  These birds quickly realise that moths are present in and around light traps and will pick off moths that settle around the trap. Indeed, Wrens will enter traps to take the moths but thankfully this is uncommon.

After the moths are identified and counted, moth trappers place the moths in deep vegetation to limit losses. It is interesting that many moths trapped in autumn will fly into trees and scrub when released, which helps to explain why Blue Tits in particular forage among sylvan foliage with such focus.

Blair’s Shoulder-knot flies during autumn and is well adapted to rest on stone walls, tree trunks and fence posts during the day. This moth has colonised Ireland probably as a result of planting Monterey, Lawson’s and Leyland Cypress.

A well-named moth flying now is the Figure of Eight, a species with a scattered distribution and rarely seen in high numbers. Even in areas known for it, this moth does not appear every year, despite systematic monitoring. It is ranked Near Threatened on the Moth Red List published in 2016. Its scarcity does not appear to be linked to foodplant specialisation, because it uses a range of common trees.

Another common autumn-flying moth is the Black Rustic. With its black cloak-like wings, it is the perfect Halloween moth!

An attractively patterned moth that breeds on Common Hawthorn, Common Blackthorn, Crab Apple, Rowan and other trees is the Green-brindled Crescent. This moth mixes a dusting of metallic green, tawny brown and off-white, blending to perfection on lichen-covered boughs.

A moth that flies in one generation from August to October and has the muted colouring that befits the season is the Large Wainscot. This moth breeds on Common Reed (which explains why the species occurs in my garden). The caterpillar feeds inside the plant’s roots and the stem bases.

A real autumn beauty, widespread and common, but not very abundant, is the Merveille du Jour.  This moth is a deeper green overall when freshly emerged than the example shown here, and is a real delight for moth lovers.

If you do not have a light trap, check the outdoor light during mild nights. You will not see the same number or range of species that appear in light traps, but you will see some of our moths. If you would like us to identify them, send a photo to us at conservation.butterfly@gmail.com.

All photographs J. Harding

 

 

 

Now it’s late September and the heat of summer has passed. We enjoyed a gentle transition from summer into autumn and our adult butterflies and moths are making the most of the opportunity, feeding for hibernation (Small Tortoiseshell, Herald Moth, Comma butterfly), migration (Painted Lady, Red Admiral, Silver Y moth), or breeding (Speckled Wood, Large, Small and Green-veined Whites).

Caterpillars are still present, some very busy feeding before cold weather sets in. In my garden, Oak/Northern Eggar moth larvae are feeding on Common Blackthorn leaves but feeding is brief, with most of the time spent basking and resting. You can see a photograph of this below. While most of my meadow is cut and added to the compost, I left some uncut areas, including the area where my Oak/Northern Eggar caterpillar lives. These uncut areas are refugia for over-wintering invertebrates, such as ladybirds and shield bugs.

A highlight of my garden this September is a lovely female Comma, who stayed for four days taking advantage of my Devil’s-bit Scabious, which she shared with bees and hoverflies. She was easy to photograph, being so focussed, and my hope of having this amazing butterfly stay in my garden is now satisfied. I wonder if she is over-wintering in my mini-woodland? I will not look for her to avoid disturbance, but this is possible. I hope to see the species breed on my nettles, but I am now being greedy!

The Green-veined White, Speckled Wood, and Red Admiral have visited in the past two days, so chances are these are still around in your garden, but soon very few species will be seen. The autumn moths are active on milder nights, and a common species that is flying now is the Beaded Chestnut, an autumn-coloured species! Looking at the photograph below, you will see why it is suited to being on the wing in September and October.

Beyond the garden, there is still insect activity, especially in high-quality grassland habitats. At Butterfly Conservation Ireland’s reserve at Lullybeg, we care for all the species that inhabit the site, and these are all part of the community that forms the connections with the butterfly and moth populations. Common and Black Darter dragonflies remain active, and the largest and most impressive species there at this stage is the Migrant Hawker, a very active predator. Plenty of bumblebees are present, mainly on the Devil’s-bit Scabious, especially Common Carder Bees, some looking very fresh. This species is happy in gardens too, and will even nest in gardens left to grow a little wild. The Forest Cuckoo Bumblebee, shown below, remains active. This species invades the nests of the Early Bumblebee and Heath Bumblebee; both of these will appear in flower-rich gardens. A female Forest Cuckoo Bumblebee is shown below.

There are other late wildflowers to enjoy, besides Devil’s-bit Scabious. Rough Hawkbit is plentiful in its haunts, a cheery flower and much loved by insects. Late-flowering honeysuckle displays its played trumpet blooms on hedges, and sow-thistle waves its yellow heads along waysides and road edges-another hit with nectar seekers.

In short, don’t give up looking because summer is over. There is more to see yet!

 

 

Recent developments concerning damage and alien species encroachment at Gortnandarragh Limestone Pavement Special Area of Conservation can be read here https://butterflyconservation.ie/wp/2021/08/28/the-continuing-story-of-irelands-biodiversity-crisis/

In 2020 and 2021 Butterfly Conservation Ireland received reports of the Comma from Carlow, Cork, Dublin, Kildare, Kilkenny, Laois, Louth, Limerick, Meath, Tipperary, Waterford, Wexford, and Wicklow.  Over 120 records, some of more than one individual Comma, have been received during 2020-2021, more records than for some long-term natives such as Cryptic Wood White, Brown, Purple and Green Hairstreak and Wall Brown.

The Comma is now an established resident. Confirmation of breeding is known from Carlow, Wexford and Wicklow where eggs and larvae have been reported and it is almost certain that they are breeding in the other counties listed here. It has also been reported in County Fermanagh this year. The butterfly can be found right into late October so there is plenty of time left to see it.

Check flowering Common Dandelion, Ice Plant, buddleia, Devil’s-bit Scabious, and Common Ivy and ripe fruit such as blackberry, apple, and pear. Gardens, parks, hedges, orchards, and bright areas of woodland such as clearings, tracks, and wood edges are all favoured by late, pre-hibernation Comma butterflies.

I had the charming experience of the Comma in my County Meath garden this August and September, where it has been feeding on Common Knapweed and Devil’s-bit Scabious. Watching it at close quarters teaches a lot about its habits. It is generally found as a single specimen in autumn, unlike its close relative, the Small Tortoiseshell. It likes to feed in direct sunlight. When cloud obscures direct sunlight, it will bask on a leaf low down, or on the bare ground but unlike the Small Tortoiseshell and Peacock it is less likely to remain long in such places if there is prolonged cloud cover.

When it remains cloudy, it usually flies high into a tree or near the top of a hedge, settling in a sheltered but open location. It will bask there when the direct sunlight returns and often remain there for some time before resuming feeding. It is easily the most arboreal of all the vanessids, aside from the Silver-washed Fritillary. The vanessids are the colourful species in the family Nymphalidae, such as the fritillaries and the Peacock.

Because it feeds alone, it appears to be less vulnerable to bird attacks than species that congregate in abundance at feeding areas. Like its relatives, it will remain in a garden with high nectar content for some days before moving to a new feeding area or entering quiescence for the winter.  Unlike the Small Tortoiseshell and occasionally the Peacock, it makes no attempt to over-winter in a house or outbuilding. It needs woodland, probably an area of dense cover, in which to pass the winter.

One of the problems with the vanessids is separating the sexes, which appear alike in most of the species. I am going to look at the Comma in a little detail to try to describe how this can be done.

Firstly, I will look at the size. The female has a slightly larger wingspan than the male. The wingspan range in the species is 50-64mm, with females at the upper end of the range.

Next, I will consider the colour. There are two colour forms in the Comma. The over-wintering cohort (which consists of two generations) is darker than the generation of  Commas that breed in mid-summer. The form that overwinters and breeds the following spring is known as the dark form. This form has an orange-red ground colour on the upper surfaces of the wings. Males are slightly deeper or darker in colour.

The short-lived, direct-breeding summer generation is golden-coloured on its uppersides; this flies mainly during July and the first half of August. This is known as the light or golden form. Again, males are smaller and slightly darker.

The best way to separate the male and female of the over-wintering dark generations based on appearance is by looking at the underside of the forewing. In the male, there is a darker band present in the forewing margin, in the scalloped area of the forewing. This is shown in the following two photographs, which show the dark form of the Comma (the form that overwinters as an adult butterfly and breeds the following spring). The male underside is often more variegated in colour but there is a good deal of variation between specimens of both sexes, with many examples showing a more variegated appearance than the two examples shown below.

Separating the sexes of the golden form (light form) that breeds in mid-summer based on the insect’s appearance is trickier. The sexes look very similar but, as is the case with the dark form, the indented area on the forewing leading edge (costa) is deeper and the tails on the hindwing are narrower and appear slightly longer in the male.

Looking at the underside of the golden form, the male’s underside is generally darker. Look closely at the two photographs underneath this text.

Separation of the sexes can be achieved by observing the behaviour of the butterfly but this applies only to breeding individuals in April and May and July and August when the males are territorial. They perch using an upright, alert posture on a leaf at the edge of a ride or clearing, ready to fling themselves at any nearby male to offer fierce resistance, often resulting in a two or three-way fight, flying vertically with impressive power. Males will also patrol a clearing especially given sustained warmth and sunshine, usually returning to the perch post it flew from unless he meets a receptive female. Females do not pursue each other or males. They spend more time basking, feeding and fluttering gently around nettles on which the eggs are laid, usually singly, on the upper surface of the leaf of its foodplant, very close to the edge. On hatching, the newborn caterpillar moves to the underside to feed.

Differences in the appearance of the sexes can be very hard to see in the wild, and harder when one only is seen. For me, it is easier to use behaviour as the distinguisher. However, the sexes are easier to separate than the Small Tortoiseshell, Peacock, Red Admiral and Painted Lady which look identical apart from subtle differences in the shape of the abdomen. As for the butterfly itself, it identifies the sex of other Commas easily, as can be seen when observing breeding individuals, especially when rival males encounter each other!

Why you might ask, are there two colour forms in this butterfly? The answer is complicated but essentially it is connected with the breeding and overall survival strategy. The Comma with the darker pigmented wings lives much longer than the light form that breeds shortly after emerging, then quickly dies. Long life requires the nitrogen sourced from foodplants to be concentrated in the thorax to strengthen it and in the wings, which are darkened to provide effective concealment among fallen leaves and woodland debris. The dark colour makes it harder for birds and mice to find. The golden form Comma breeds immediately so it does not need to have a long life. In this form, the nitrogen is concentrated in the abdomen so that the eggs and sperm are ready for early reproduction.

The factors that influence the development of light and dark form adult Commas have been identified as photoperiod (hours of daylight, especially direct sunlight), temperature, the nutritional quality of the foodplant and the species of foodplant used by the larva. In essence, larvae that receive the best nutrition in the warmest temperatures with the highest daylight hours are more likely to produce the golden form. This means the Comma will fit in two full generations in years with sunny, warm springs as long as they are feeding on foodplants growing on fertile, moist soil. The foodplant that is mainly (or solely?) used in Ireland is Stinging Nettle, although it also uses Hops and Wych Elm in Britain.

It is likely that these are the years when the Comma disperses further and has higher survival rates over the winter. We have, thanks to our recording scheme and your records, established that the Comma is producing two full broods in Ireland, the golden form as the first generation followed by their dark offspring. We have also learned that in some areas and or under certain conditions the Comma is also producing just one generation that will enter hibernation in summer, and will therefore need to survive three extra months before breeding the following spring. This may be happening when there is an overcast, cool spring or when an old female lays her last eggs in June which means the resulting caterpillars hatch or develop when daylight starts to decline and the skies are generally cloudier than they are during spring.

This complex breeding strategy provides survival safeguards for this intriguing butterfly, and the more that is learned about the species, the more insights are provided into the complexities of its relationship with the biotic and non-biotic elements of its environment, and in the deeper interconnectedness of the ecosystems.

Meanwhile, we are delighted to see this very lovely butterfly expanding from the southeast northwards and westwards, so keep sending us your records to help us to track its progress.

If you have a question about this butterfly, feel free to ask. Email: conservation.butterfly@gmail.com

All photographs © J. Harding.

Although nocturnal and rarely encountered during daylight, the following is a selection of important moths that inhabit gardens with native plants at this time of the year. These pollinate our flowers, control plant growth, feed our birds, bats, hedgehogs, and frogs, and are a vital part of the ecosystem. All come to light, so there is a chance to see these species, and while many of these roost in trees during the day, some will be found resting on walls and tree trunks. Allow nettles, native grasses, flowers, trees and flowering ivy to grow in your gardens to look after these moths. Their flight period and breeding plants are stated in the captions.

Photos J. Harding

 

Recent reports by good investigative journalists give a comprehensive and accurate picture of the neglect and degradation of Ireland’s legally protected sites. One report can be read here:

https://www.thejournal.ie/endangered-species-part-1-5520770-Aug2021/.

These reports, while informative, contain copious detail that can overwhelm the reader.

Here we focus on a single example.

Gortnandarragh Limestone Pavement is located on the southern side of Lough Corrib, about 7 km south-east of Oughterard in County Galway. The site extends to about 347 hectares in area and it is a Special Area of Conservation.

It consists of an exposed limestone plateau that slopes down on its eastern side to cut-over fen and bog. Parts of the pavement exhibit a well-developed system of clints and grykes, while other parts are shattered, with much loose rock. The pavement forms a mosaic with heath, grassland and scrub. To the east, the limestone habitats grade into fen and blanket bog. Much of the central part is open but the eastern side contains enclosures and is grazed by cattle.

The beautiful flora characteristic of limestone pavement and associated dry calcareous grassland occurs here. Examples include Bloody Cranesbill, Wild Thyme Thymus praecox, Spring Gentian Gentiana verna, Carline Thistle Carlina vulgaris, Mouse-ear Hawkweed Hieracium pilosella, Devil’s-bit Scabious Succisa pratensis, Kidney Vetch Anthyllis vulneraria, Goldenrod Solidago virgaurea, among others.

Small trees present in the more open areas include Common Juniper (frequent), Common Yew, Common Blackthorn, Common Hawthorn, and whitebeam, probably Irish Whitebeam. This tree, assessed as vulnerable on Ireland Red List No. 10 Vascular Plants is an endemic plant. Less than 1000 individual Irish Whitebeams are believed to exist. On the southern section, well-developed woodland exists, with Common Ash and oak over a Common Hazel understorey, with some Aspen.

The entire site is of great interest for biodiversity, but some key areas for butterflies include the grassy track at M 19535 40913 (Corranellistrum), which holds Small Blue and probably Marsh Fritillary, while Brimstone and Brown Hairstreak have been recorded among the scrub immediately adjoining this grassy area to the north. The rare moth, Straw Belle Aspitates gilvaria ssp. burrenensis flies here in July.

The long track running east from M 19706 40304 provides easy walking through open limestone grassland, pavement, heath, scrub and eventually onto bog at M 20517 39967 (Kylemore). A range of butterflies can be found along this track, especially Dark Green Fritillary, Grayling, Meadow Brown, Ringlet and Small Heath. Interestingly, the Small Heaths found where the grassy area grades into the bog are large and easily confused with the Large Heath butterfly. Walking south along the road that runs from north to south through the site, the area becomes increasingly wooded and Silver-washed Fritillary and Speckled Wood are well represented here, such as at Garrynagry (M 19480 39687). Overall, the more flower-rich open areas with scattered scrub are rich in butterflies, and this site deserves to be much better known.

The site’s status as a Special Area of Conservation means the area is legally protected from a range of activities that can cause damage, such as land clearance, peat-cutting, land cultivation, drainage, wall construction, removing or disturbing rock, among other activities. The Statutory Instrument S.I. No. 492/2018 – European Union Habitats (Gortnandarragh Limestone Pavement Special Area of Conservation 001271) Regulations 2018 makes this clear, and states the penalties that may apply on conviction and who may take a prosecution:

6. (1) A person who carries out, causes or permits to be carried out, or assists in the carrying out of an activity referred to in Regulation 5(1), without a consent or otherwise than in accordance with a consent given by the Minister under Regulation 30 of the Regulations of 2011, commits an offence and is liable—

(a) on summary conviction, to a class A fine or to imprisonment for a term not exceeding 6 months, or both, or

(b) on conviction on indictment, to a fine not exceeding €500,000 or to imprisonment for a term not exceeding 3 years, or both.

6 (3) Proceedings for an offence under paragraph (1) may be brought summarily by—

(a) the Minister,

(b) the public authority concerned, or

(c) a member of the Garda Síochána, in accordance with section 8 of the Garda Síochána Act 2005.

One of the functions of the National Parks and Wildlife Service is to protect Special Areas of Conservation. Conservation Officers (rangers) make site visits to keep a watch on the condition of our special areas.

In July 2021 damage was seen on the site and a record of the locations was made, with supporting photographs. The damage consists of peat cutting on the bog which lies within the boundary of the Special Area of Conservation. The bog is intrinsically important, as well as being the type locality of the endemic fungus, Entomola jennyi, a toadstool, which has been found in a very small number of locations. Cleared woodland, cleared limestone, wall construction using local limestone and the collection of stone, presumable for removal and use in building the stone walls fronting several local houses, and possibly for use as outer-leaf facing stone, were observed. Further threats to the limestone habitat are the appearance of alien invasives, including cotoneaster, and the encroachment of native scrub on the karst.

Butterfly Conservation Ireland contacted the area’s Conservation Officer and we received an acknowledgement and request for supporting information. Butterfly Conservation Ireland provided the information on August 30th, August 3rd and August 4th, 2021. After receiving no response from the Conservation Officer regarding any action taken, contact was again made by Butterfly Conservation Ireland asking whether the Conservation Officer wanted to make a statement for this report. The Conservation Officer directed Butterfly Conservation Ireland to the Department’s press office press@housing.gov.ie for an official comment. Butterfly Conservation Ireland contacted the Department on August 19th 2021. No acknowledgement or comment from the Department has been received to date (August 28th 2021).

We suggest that a daily report detailing the latest national ecological news be broadcast on RTE Radio’s Morning Ireland programme. It will not lack material.

Report Update

A reply was received from the Press Office of the Department of Housing,  Local Government and Heritage on 7th September 2021.

The reply is set out below. Note: BCI did not correct any grammatical or spelling issues in the following reply.

1 Gortnandarragh Limestone Pavement SAC is designated for Limestone Pavement. 

2 The reclamation that was complained of appears to be old and not of recent origin.

3 Fencing that was noted on site appears to consist of wooden posts for electric fencing and are not of a permanent nature.

4 There is an issue with the spread of invasive cotoneaster.  This is species is an problem in a number of others sites such as the Burren SACs and some eskers.  This would need to be addressed by means of some form of management plan but there is no immediate action that can be taken in respect of this problem.

5 As peat habitats are not qualifying interests for the site, it is not proposed to introduce any restrictions on this activity.

6 Some activity noted appears to be taking place outside of the SAC.

7 NPWS regional staff will continue to monitor the site.

Butterfly Conservation Ireland responded as follows.

Dear …..,

Thank you for your response.

Regarding Point 1

We accept that the site is designated for limestone pavement but important features, such as Juniper formations, do not exist independently of the designated habitat. These may be threatened by developments such as land clearance and cotoneaster encroachment. In regard to the land clearance issue, we trust that site packs have been issued to the landowners.

Regarding Point 2

The date of land reclamation on a limestone pavement site can be difficult to determine without dated photographs.

Regarding Point 3

The issue of concern did not include fencing but pertained to the construction of stone walls consisting of local slabs of limestone that can only be lifted by machinery. As the site is designated for limestone pavement, this issue is important and is prohibited by the Statutory Instrument (SI).

A photograph of the stone wall was included in my report to the ranger and can be seen at https://butterflyconservation.ie/wp/2021/08/28/the-continuing-story-of-irelands-biodiversity-crisis/

Regarding Point 4

It is important to point out the cotoneaster is at an early stage of encroachment, so prompt action now will prevent serious problems from developing.

Regarding Point 5

Regarding the site’s qualifying interests not including peat habitats, the site map in the SI appears to include the bog. Furthermore, the conclusion of the site synopsis (prepared by the National Parks and Wildlife Service) states:

“Gortnandarragh is valuable as an example of limestone pavement, an internationally important habitat which is listed with priority status, on Annex I of the E.U. Habitats Directive. It is also notable because the bog on the site is the type locality and only known station for Entoloma jennyi. Furthermore, there are interesting and diverse areas of heath, grassland, scrub and woodland, all contributing to a valuable site of considerable conservation interest”.

Regarding Point 6

The activity noted may be taking place outside the SAC boundaries but this is not established clearly in your response. The site maps can be found in the SI. These should be checked.

Regarding Point 7

We are encouraged to learn that NPWS regional staff will continue to monitor the site. We trust the regional staff will take the actions required to protect the site from damage.

Jesmond Harding
Conservation Officer
Butterfly Conservation Ireland

Butterfly Conservation Ireland is not satisfied with the response received. The deterioration of our legally protected sites bodes ill for the rest of our landscape. We need everyone to realise the farce often played out concerning biodiversity. If anyone is looking for a symbol for the absence of care for our biodiversity by our government and state, look at where the National Parks and Wildlife Service is based. It is currently located within the Department of Housing, Local Government and Heritage. Note that heritage appears last in the list, itself emblematic of the priority accorded to biodiversity. Butterfly Conservation Ireland invites members of the public to write to Malcolm Noonan, TD, Minister of State for Heritage and Electoral Reform (the Minister responsible for the National Parks and Wildlife Service )and Pippa Hackett, TD, Minister of State and Spokesperson for Land Use and Biodiversity and ask why our special places are allowed to be damaged, and why the National Parks and Wildlife Service does not have the status, resources and leadership that reflects the urgent need to tackle our biodiversity crisis.

Malcolm Noonan https://www.oireachtas.ie/en/members/member/Malcolm-Noonan.D.2020-02-08/, https://www.malcolmnoonan.com/get-in-touch

Pippa Hackett https://www.oireachtas.ie/en/members/member/Pippa-Hackett.S.2019-11-01/, https://www.greenparty.ie/people/pippa-hackett/

 

 

 

At 2 am on Tuesday 17th August 2021 the temperature in Malta was 30 Celsius while at 8 am it was already 33 Celsius in Spain where the reporter talking on RTE radio (the Irish state broadcaster) was based. Europe generally is reeling from the extreme conditions while I write (17th August 2021). In addition, recent heavy flooding in France, devastating flooding earlier this summer in Germany and Belgium and temperatures recently exceeding 48 Celsius in Sicily support the conclusions of the Intergovernmental Panel on Climate Change (IPCC) that the climate is changing, rapidly. In the IPCC’S Sixth Assessment Report (AR6), a range of data points to rapid changes that are, the report claims, in some cases irreversible.

The headline statement in AR6 is

It is unequivocal that human influence has warmed the atmosphere, ocean and land. Widespread and rapid changes in the atmosphere, ocean, cryosphere and biosphere have occurred.

 Given the tendency of scientific reports to employ cautious, often nuanced and restrained language, this statement is unusually clear. The statement is followed by a mass of data revolving around the impacts of well-mixed greenhouse gas (GHG), methane, carbon dioxide and nitrous oxide on our climate. These concentrations increased from 2011 when measured in 2019.

Each of the last four decades has been successively warmer than any decade that preceded it since 1850. Global surface temperature in the first two decades of the 21st century (2001-2020) was 0.99 [0.84- 1.10] Celsius higher than 1850-1900. The estimated increase in global surface temperature since AR5 (the IPCC’s fifth report) is principally due to further warming since 2003–2012 (+0.19 [0.16 to 0.22] Celsius). The likely range of total human-caused global surface temperature increase from 1850–1900 to 2010–2019 is 0.8 Celsius to 1.3 Celsius, with a best estimate of 1.07 Celsius.

The report states the causes and impacts.

Human influence is very likely the main driver of the global retreat of glaciers since the 1990s and the decrease in Arctic sea ice area between 1979–1988 and 2010–2019 (about 40% in September and about 10% in March).

Human influence very likely contributed to the decrease in Northern Hemisphere spring snow cover since 1950. It is very likely that human influence has contributed to the observed surface melting of the Greenland Ice Sheet over the past two decades…

 It is virtually certain that the global upper ocean (0–700 m) has warmed since the 1970s and extremely likely that human influence is the main driver. It is virtually certain that human-caused CO2 emissions are the main driver of current global acidification of the surface open ocean. There is high confidence that oxygen levels have dropped in many upper ocean regions since the mid-20th century, and medium confidence that human influence contributed to this drop.

The global mean sea level increased by 0.20 [0.15 to 0.25] m between 1901 and 2018. The average rate of sea-level rise was 1.3 [0.6 to 2.1] mm yr–1 between 1901 and 1971, increasing to 1.9 [0.8 to 2.9] mm yr–1 between 1971 and 2006, and further increasing to 3.7 [3.2 to 4.2] mm yr–1 between 2006 and 2018 (high confidence). Human influence was very likely the main driver of these increases since at least 1971.

Globally averaged precipitation over land has likely increased since 1950, with a faster rate of increase since the 1980s (medium confidence).

Human-induced climate change is already affecting many weather and climate extremes in every region across the globe. Evidence of observed changes in extremes such as heatwaves, heavy precipitation, droughts, and tropical cyclones, and, in particular, their attribution to human influence, has strengthened since AR5.

 These effects will continue, according to the report:

Global surface temperature will continue to increase until at least the mid-century under all emissions scenarios considered. Global warming of 1.5 Celsius and 2 Celsius will be exceeded during the 21st century unless deep reductions in CO2 and other greenhouse gas emissions occur in the coming decades.

Continued global warming is projected to further intensify the global water cycle, including its variability, global monsoon precipitation and the severity of wet and dry events.

 …the global water cycle will continue to intensify as global temperatures rise (high confidence), with precipitation and surface water flows projected to become more variable over most land regions within seasons (high confidence) and from year to year (medium confidence).

A warmer climate will intensify very wet and very dry weather and climate events and seasons, with implications for flooding or drought…

Under scenarios with increasing CO2 emissions, the ocean and land carbon sinks are projected to be less effective at slowing the accumulation of CO2 in the atmosphere.

While natural land and ocean carbon sinks are projected to take up, in absolute terms, a progressively larger amount of CO2 under higher compared to lower CO2 emissions scenarios, they become less effective, that is, the proportion of emissions taken up by land and ocean decrease with increasing cumulative CO2 emissions. This is projected to result in a higher proportion of emitted CO2 remaining in the atmosphere (high confidence).

Mountain and polar glaciers are committed to continue melting for decades or centuries (very high confidence). Loss of permafrost carbon following permafrost thaw is irreversible at centennial timescales (high confidence). Continued ice loss over the 21st century is virtually certain for the Greenland Ice Sheet and likely for the Antarctic Ice Sheet. There is high confidence that total ice loss from the Greenland Ice Sheet will increase with cumulative emissions. There is limited evidence for low-likelihood, high-impact outcomes (resulting from ice sheet instability processes characterized by deep uncertainty and in some cases involving tipping points) that would strongly increase ice loss from the Antarctic Ice Sheet for centuries under high GHG emissions

It is virtually certain that the global mean sea level will continue to rise over the 21st century.

The sea level is committed to rise for centuries to millennia due to continuing deep ocean warming and ice sheet melt and will remain elevated for thousands of years (high confidence). Over the next 2000 years, the global mean sea level will rise by about 2 to 3 m if warming is limited to 1.5 Celsius, 2 to 6 m if limited to 2 Celsius and 19 to 22 m with 5 Celsius of warming, and it will continue to rise over subsequent millennia (low confidence).

All this information is frightening. Looking at the light rain outside this morning, and the typical August cloud cover, it is often hard to interpret climate change data in an Irish context. But the data pertaining to climate change exists for Ireland too. Rainfall has increased in all seasons since the mid-1980s. Carbon dioxide levels are higher.

The report from the Republic of Ireland’s Environmental Protection Agency, Met Éireann and Marine Institute shows that the air temperature has risen by almost 1 Celsius in the last 120 years, with 15 of the top 20 warmest years on record having occurred since 1990.

Ireland’s Role in Climate Change

A major source of GHG gas in Ireland is agriculture. According to the Department of Agriculture, Ireland has 3.8 million sheep, while the Central Statistics Office figures show there are 6.5 million cattle and nearly 1.7 million pigs, all producers of methane gas. Globally, it is the second most important greenhouse gas (GHG).

According to Teagasc, the farmer advisory body in the Republic of Ireland, its contribution to global warming is estimated at 28 times that of Carbon dioxide, over a 100-year period. Once produced, methane persists in the atmosphere for around 12 years after which it is eventually broken down into Carbon dioxide and water. The reporting of Irish GHG emissions in 2020 attributes 58% of Irish Agri emissions to methane produced by the rumen (part of the digestive system) of cattle and sheep. A further 10% of national agricultural emissions originated from methane associated with the storage of manure and slurry. This is produced by microbes that have passed through the animal in the faeces. Methane associated with ruminant livestock production accounts for two-thirds (68%) of Irish agricultural GHG emissions.

Added to this is the amount of fertiliser applied to grazing land. Nitrates are strongly implicated in climate change. Nitrous Oxide N2O, which arises from nitrate fertiliser is a major GHG. N2O is a long-lived greenhouse gas that is almost 300 times more potent than CO2 over a 100-year period. It is the third-largest contributor to climate change after CO2 and methane. In addition, nitrates pollute the soil and rivers, damaging wildlife, and human health. The manufacture of nitrate fertilisers requires the burning of fossil fuels, adding to N20 emissions.

(Sources: International Journal of Environmental Research and Public Health and https://www.carbonbrief.org/nitrogen-fertiliser-use-could-threaten-global-climate-goals)

What is Ireland’s answer to climate change?

Here I look at the issue of how we treat one landscape feature, our peatlands, which have an important role to play in addressing biodiversity loss and climate change.

Instead of restoring and protecting our peatlands, we are doing the very opposite. But before looking at the damage being done, let me outline the role peatlands play in climate change.

According to the Environmental Protection Agency (EPA) peatlands play a vital role:

Peatlands are major contributors to the biological diversity of regions throughout the world and provide a variety of goods and services in the form of forestry, energy, flood mitigation and maintaining reliable supplies of clean water. In light of future climate change, the most important function of peatlands in the 21st century is that of a carbon store and sink. Covering only about 3% of the Earth’s land area, they hold the equivalent of half of the carbon that is in the atmosphere as carbon dioxide (CO2) (Dise, 2009). It is estimated that the carbon stored in peatlands represents some 25% of the world soil carbon pool (i.e. 3–3.5 times the amount of carbon stored in the tropical rainforests. (Parish et al., 2007)(http://erc.epa.ie/safer/reports).

Devastating damage is done to peatlands globally:

In a recent assessment, it was estimated that, globally, natural peatlands are being destroyed at a rate of 4,000 km2/year (Parish et al., 2007)(http://erc.epa.ie/safer/reports).

With this extraordinary importance, you would think that in Ireland we would be protecting and restoring our peatlands with the greatest possible urgency. But no. Instead, we are destroying them. One of the solutions advanced to address climate change is windfarms.

What does the EPA say about peatland use and windfarms?

This investigation into peatland utilisation showed that neither past nor current management of peatlands in Ireland has been sustainable. Disturbances in the form of industrial and domestic peat extraction, private afforestation, overgrazing, wind farms and recreational activities have had and are having major negative impacts on the hydrology and ecology of these habitats. Natural peatlands, which are hydrologically and ecologically intact, have become rare and are being further threatened. The biggest threat to peatlands in the 21st century is likely to be climate change and its associated policies, e.g. wind farms. Rigorous examination and guidance for their full impact assessment (including a new technique developed in this project to test peat strength) are urgently required. (Source EPA http://erc.epa.ie/safer/reports)

A major announcement late in 2020 offered some hope for peatlands in state ownership when Bord na Móna, the state body that holds over 80,000 hectares of peatland, announced an end to all peat extraction on its estate (https://www.bordnamona.ie/bord-na-mona-announce-formal-end-to-all-peat-harvesting-on-its-lands/). This was followed by a government announcement to fund peatland restoration to the tune of €108 million. This would tackle climate change and biodiversity loss. (https://www.gov.ie/en/press-release/2aae1-cabinet-approves-108m-funding-for-groundbreaking-bord-na-mona-bog-rehabilitation-plan-minister-ryan-also-announces-that-47-more-projects-in-the-midlands-totalling-278m-are-approved-under-the-just-transition-fund/).

This appears wonderful. But how wonderful is it?

According to Bord na Móna’s Decommissioning and Rehabilitation Plan 2020, the rehabilitation scheme funded by the government and Bord na Móna applies to 33,000 hectares, less than half the area in the Bord na Móna estate. According to https://www.bordnamona.ie/peatlands/peatland-restoration/, only 8,100+ hectares will be restored. That is extremely unambitious, and that is a colossal understatement. What about the rest of the Bord na Móna peatlands, including those in the hands of Coillte (the forestry service in the Republic of Ireland) and those in private ownership?

Despite the positive announcements, the facts on the ground foreshadow negative projections for peatlands, biodiversity and climate change. A raft of applications by Bord na Móna and others for enormous “green energy” projects (solar farms and wind farms) on bogs have appeared,  especially shortly before and since it announced an end to its peat extraction activities. It seems we are determined to destroy our bogs, regardless of the cost.

Unauthorised peat cutting on Bord na Móna bogs continues unhindered and “Peat For Sale” signs are found in the vicinity of the bogs. I see no real effort made to stop this ruinous behaviour. Within view of the nature trail in Glenveagh National Park in Donegal, peat is being cut on a vast scale. Peat-cutting also continues on European sites (sites in Ireland and throughout the EU designated as Special Areas of Conservation) and little or no effort is made to stop this criminal activity. (This will be the subject of a future post.) The message to selfish people who destroy our environment is “keep going”.

In November 2019 we heard, perhaps vaguely, of a strange ‘Flu’ in China. Far away, it will not affect us. The WHO advised governments against imposing travel restrictions. Don’t worry, was the message. Then this ‘Flu’ reached Northern Italy. We became somewhat concerned and the Ireland v Italy rugby international was cancelled but the Italian fans travelled regardless, revelling in Dublin’s pubs. But the disease did reach our shores. So have the effects of climate change, but soon our shores may not be in the same place they are in now.

 

 

 

 

 

 

Jane Doughty and Robert Donnelly, Butterfly Conservation Ireland members living in County Kilkenny, are renowned for the abundance of butterflies in their amazing garden. Robert counted 124 butterflies in his garden in County Kilkenny on just one day, July 22nd, 2018. Silver-washed Fritillaries are seen regularly in their garden, a true Eden for butterflies. Here Jane describes their conservation journey and their efforts to broaden their commitment to conserving butterflies.

Our story at Little Eden, where, in retirement, we tend two acres of garden, is probably far from unique.

Twenty-five years ago, with just half an acre to manage and being time poor with work requirements, we used insecticides and Glyphosate without conscience. Our lawns were applied with selective weedkiller and had fresh stripes when mowed. Exotic and flora plena plants seemed irresistible and filled the borders.

Slowly and as Robbie would say “we copped on” we began noticing certain plants attracted more insects and if our own honeybee colony was to find nectar, then more suitable planting was necessary. Using commercial sprays was out altogether and so the change began.

Amongst other publications, Robbie had read Discovering Irish Butterflies & Their Habitats (for the life of me I can’t remember the author’s name) and we subsequently realised nectar sources for butterflies were not enough as each requires specific larval food plants. If we were to help the butterfly population and all the threatened living creatures local to our landscape, our response had to be broadened.

First non-native plants were replaced with the indigenous. Later, fortunately, we were able to purchase adjoining old pasture. We planted our boundaries with fruit and berry-bearing wild trees and shrubs. Grasses, nettles, thistles, and brambles were welcome (with management) and nothing now fits the description of ‘weed’.

Hiring a digger, Robbie excavated a generous unlined and spring-fed pond in the clay soil, allowing life to develop naturally in time. With hammocks under an old willow, we are now privileged to be entertained by creatures below, on, and above the waterline. Damsels and dragonflies clatter wings and swallows, house martins, and even bats impress with fantastic aerial displays when drinking and feeding.

Last year we offered excess garden produce on the road outside suggesting donations for Butterfly Conservation Ireland. This year we did the same and our young neighbour, aged 7, kindly provided wonderful images of butterflies for our sign. We have been gladdened by people’s generosity and impressed by the enthusiasm of young wildlife photographer, Sam.

As individuals, we can make only a small contribution to improve our environment which is under immense pressure in Ireland, as well as globally, and we thank those who do more.

 

 

It is a stunning, hot summer’s day, and your garden Buddleia, the one you bought to attract butterflies to your garden, is blooming to perfection, and wafting its pungent sweetness onto the still air.

All expectant, you inspect the plant each day but apart from the odd hoverfly and bee, you are not seeing much activity. Where are the butterflies that you were told would flock to feed on Buddleia? Your flowering Marjoram, a nectar-rich native herb, is not doing any better, although it has more bees.

Butterflies can be very contrary. A habitat that is perfect for a particular species just does not have it. All the ingredients are in place; plenty of nectar sources, plenty of caterpillar host-plants, the correct aspect, site size, and location but the butterfly just is not there. Elsewhere, a smaller, apparently less suitable habitat has the species in abundance.

This scenario is especially noted when it comes to habitat specialists known for their highly specific needs and poor powers of dispersal. But butterflies that frequent gardens lack such constraints. These are wide-ranging, mobile species that will occur in a broad range of habitats.

The question remains, where are they?

Timing is key.

All butterflies have a four-stage life cycle. These stages occur at different times of the year, and because it is usually the adult stage we notice, this is the stage you will cater for if you grow nectar-rich flora that blooms at the correct time.

Take the classic garden butterfly, the Small Tortoiseshell. Here is its annual phenology (timing of life cycle stages):

Adult: All year; scarce during the first half of June and second half of August
Egg: April-May, late June-mid-July, scarce in late August
Larva: May-June, mid-July-late August, scarce in September
Pupa: June-early July, August-mid-September, scarce in October.

You will see the adult flies in July and early in August. So why is it absent from my Buddleia at these times?

Here’s why. The priority of the adult Small Tortoiseshell varies depending on certain factors, especially photoperiod (the period of time each day during which an organism receives illumination; day length).

When the day length is long and increasing in May and June, the adult Small Tortoiseshell is focused on reproduction, not on feeding on nectar. Daylight hours are very high in July, although declining slowly, so the adult Small Tortoiseshell is still keen on breeding. Therefore it frequents breeding areas where nettles grow, rather than feeding areas.

If the mid-summer weather is poor and overcast, part of the Small Tortoiseshell population enters a reproductive delay. When this happens, this section of the population visits gardens and other places where nectar is found in order to build fat reserves to prepare to pass the winter as an adult butterfly. When this happens, you will see the butterfly in your garden in July. After over-wintering, it will breed in spring.

This July the Small Tortoiseshell was busy breeding and very few entered a reproductive delay. The offspring of the June and July breeders will  emerge in late August and September, and this generation of Small Tortoiseshells will flock to flower-filled areas. This generation, with rare exceptions, will delay breeding until next spring, and to survive until then they need as much nectar as possible.

I hope that you don’t mind if I throw climate change and weather variability in the mix at this point. Day length is not the only environmental signal that the Small Tortoiseshell responds to. It is highly likely that it responds to signals from its larval host plant too. In hot, very dry summers, like the summer of 2018, days are sunny and daylight hours are long but drought makes the nettles less nutritious and even unsuitable for breeding. It appears that the Small Tortoiseshell is responding to this by canceling its second generation and entering the over-wintering state as early as July.

There are documented examples of this response in St Albans, Hertfordshire, where the butterfly went into early hibernation in some years. In 2017 and 2018, all the Small Tortoiseshells that hibernated in Malcolm Hull’s home were hibernating by July 7th and August 5th, respectively. At Howth, in County Dublin, Mr. Frank Smyth, a careful observer and recorder of butterflies has noted the absence of Small Tortoiseshells at Howth, County Dublin during August and September in some years but their reappearance the following spring. The butterfly may be skipping its second generation at Howth too, and this may occur in other dry east coast locations during dry summers. A skipped second generation might also occur during cold summers. This ability to modify its brood strategy suggests a high level of adaptability, much needed by a widely distributed species in an era of climate change.

Aside from dry, free-draining areas during long, hot summers and cold, overcast, wet summers, we can expect to see Small Tortoiseshells, and their close relations, in our gardens during August and September. This is when you will see the big influxes of butterflies in the garden, and these big occurrences are what give the illusion that summer is never-ending, while in reality, the appearance of butterflies is a clue that winter’s shadow is clouding the horizon. Butterflies know that winter is coming because they can sense the accelerating decline in daylight even if the temperature remains high.

In this way, butterflies remind us of the season’s signals, and of cyclical changes.

Over the next few weeks, you should see plenty of butterflies in your garden if you are giving them nectar-rich flowers. If you are providing flowering Common Ivy, and nettles, you will see even more!

Let us know what you see. Tell us by email at conservation.butterfly@:gmail.com

Let us know:

your first name/s, and surname/s

your contact details (typically an email address)

date of the find,

species found,

the life stage/s found,

numbers seen,

location the butterfly/moth was found (e.g. townland name, site name, county),

six-figure grid reference, including the letter identifying the 100,000-metre grid square in which the location lies (see http://www.gridreference.ie/ or Discovery Series maps)

weather conditions

and any other interesting comments you wish to provide.

Example:

John Smith (14/06/2020)

Small White 2, Small Copper 1, Small Blue 14, Small Heath 15 at O254515, Portrane sand dunes, County Dublin. Sunny, light breeze, 18 Celsius.

It will be greatly appreciated if recorders send in their records by listing the butterflies observed in the following order:

Small Skipper, Essex Skipper, Dingy Skipper, Common Swallowtail, Wood White, Cryptic Wood White, Clouded Yellow, Brimstone, Large White, Small White, Green-veined White, Orange-tip, Green Hairstreak, Brown Hairstreak, Purple Hairstreak, Small Copper, Small Blue, Common Blue, Holly Blue, Red Admiral, Painted Lady, Small Tortoiseshell, Peacock, Comma, Pearl-bordered Fritillary, Dark Green Fritillary, Silver-washed Fritillary, Marsh Fritillary, Speckled Wood, Wall Brown, Grayling, Hedge Brown/Gatekeeper, Meadow Brown, Ringlet, Small Heath, Large Heath, Monarch.

If you like, you can take part in our Garden Butterfly Survey. It’s easy to do and the form is available here: https://butterflyconservation.ie/wp/wp-content/uploads/2017/12/National-Garden-Butterfly-Survey.pdf

Here are some butterflies you might see in the next 6 weeks. The white butterflies shown in the previous post will also feature. Enjoy!