It is December 8th and the Met Office is forecasting a bitterly cold month ahead. How will this impact on our butterflies? Butterflies are regarded as creatures of the light, lovers of sunshine and warmth, vulnerable to the onslaught of bitter winters. We rarely have cold winters and with climate warming we may get even fewer, so how will this change the fortunes of our butterfly and moth populations? The connection between extreme winter warmth and butterfly population levels was researched by East Anglia University, Butterfly Conservation UK and the Centre for Ecology and Hydrology (McDermott Long, O., Warren, R., Price, J., Brereton, T. M., Botham, M. S. and Franco, A. M. A. (2017), Sensitivity of UK butterflies to local climatic extremes: which life stages are most at risk?. J Anim Ecol, 86: 108–116. doi:10.1111/1365-2656.12594).
It was already known that butterflies do better in warmer summers but, perhaps unexpectedly, the new research which looked at the impact of extreme climate events on the population of butterflies in the UK from 1976-2012 revealed that extreme mild winters have a negative effect on the populations of just over half of the 41 species studied. It is interesting to observe that these negative effects occurred regardless of whether the species affected are widespread species or habitat specialists. All four of our butterflies that over-winter in the adult form, the Comma, Small Tortoiseshell, Peacock and Brimstone showed a negative impact of extreme winter warmth (disruption of over-wintering in these species may result in losses from predation and decline in fat reserves). Species that showed a similar result and the stage in which these over-winter are the Purple Hairstreak (egg), Dingy Skipper and Dark Green Fritillary (larva) and Orange-tip (pupa).
Only two of the species studied showed that there is a positive effect of warm winters; these were Wall Brown and Holly Blue. Extremely cold winter days were associated with significant population increases in the Large White (over-winters as a pupa) and Ringlet (over-winters as a larva).
Overall, the study found that cold spells in winter were beneficial or neutral in the impacts on population size while warm spells in winter were generally harmful. An additional and unexpected finding is that the pupa of butterflies that have one brood per year show sensitivity to extreme precipitation.
Another recent study, from Stockholm University also using data from the UK (Stålhandske, S., Gotthard, K. and Leimar, O. (2017), Winter chilling speeds spring development of temperate butterflies. J Anim Ecol, 86: 718–729. doi:10.1111/1365-2656.12673) found that some butterflies that over-winter in the pupal state emerge earlier in the year during a warm spring but not after a warm winter. Three species of the five species studied, Green-veined White, Orange-tip and Green Hairstreak flew earlier in spring after a cold winter. The study found that warm winters delay emergence. This earlier spring emergence might be due to the insect being programmed to emerge from the pupa after experiencing a prolonged period of cold followed by a period of warm conditions; this temperature change process is used to obtain specimens out of season in captivity. This involves placing a pupa in a refrigerator for some weeks and then keeping it at room temperature which causes early emergence, mimicking the effects of the passing of winter and onset of spring.
With climate change expected to continue, what are the main implications for our species? The findings are mixed. Warmer summer weather, as long as drought does not occur, may well help populations to increase and spread. Extreme climate events, such as extreme warmth and extreme rainfall in winter may cause declines. High quality habitats may have the ability to buffer extremes, so it is vital that habitats are managed as carefully as possible to provide the best chance of survival for our butterflies and moths.
When you see the snow and ice over the coming days, please take care, but remember that our butterflies are well-adapted to these conditions which may be necessary for their long-term survival. Snow and butterflies are compatible!
Weather-reliant activities are hard to plan in Ireland and Saturday 11th November, promised dry two days before, slowly descended into a wearying drizzle.
Undeterred, the Butterfly Conservation Ireland work party knuckled down to do battle with regenerating scrub close to where scrub was tackled last year. Our youngest workers, Annie and Conor helped by enthusiastically tucking into the work of uprooting birch saplings and cutting young re-growth on willow and birch. Taller material was felled and the resulting cuttings piled neatly to rot down naturally. A great impression was made on the encroaching scrub with these areas now much more open to light, creating breeding sites for grassland butterflies like the Marsh Fritillary, Dingy Skipper and Common Blue.
The process of halting and reversing natural succession (the process of change in biological communities over time) at Lullybeg is needed to ensure that the climax vegetation in much of the managed area of the reserve remains species-rich grassland. Left to develop its climax vegetation naturally, the site will become woodland dominated by birch and willow and its grassland butterflies would be lost. The grassland butterflies and moths specialise on herbs growing in a grassy sward that is open and unshaded. The shading of grassland reduces the light and temperature, making these areas unsuitable for breeding for most of the reserve’s butterflies. Some butterflies, like the Brimstone, breed in open scrub while the Silver-washed Fritillary likes open, sunlit woodland. There are areas of the reserve where the needs of these species are accommodated. In this way, a habitat mosaic is provided, with a range of habitats scattered throughout the site which are maintained by active conservation management.
Butterfly Conservation Ireland thanks everyone who made a vital contribution to conserving the butterflies moths and other insects on this rich site. We will have another conservation day in February, when we hope for bright spring sunshine!
The Brown Hairstreak is one of our most elusive yet most conspicuous butterflies. The adult is rarely seen but the egg is easily found. This paradox may be part of the butterfly’s appeal. Among butterfly lovers in the UK the Brown Hairstreak has a cult status, evidenced by having its own blog (http://betulae.blogspot.ie/). It is an attractive butterfly, the female especially delightful with a warm golden underside with a patch of the same striking hue on the upper-side of the fore-wings. Aside from the golden patch the upper-sides are dark brown. Males look similar, but the underside gold is paler and the fore-wing patch paler and reduced or absent. The reddish-gold tails on the hind-wings add to its charms. The legs are a striking white, resembling starched white sport socks.
The Brown Hairstreak is the largest hairstreak in Ireland and is not common here or in Britain (we have three hairstreaks; the Green Hairstreak and Purple Hairstreak are the others). In Ireland it is mainly found in the Burren in Clare and Galway, with a small population in west Tipperary and west of Lough Corrib, County Galway. In Britain it is mainly found further south, in south-west Wales, southern, south-west and south central England with a small population in the east, in Lincolnshire.
The butterfly is single-brooded, flying from late July to mid-September. It breeds on hedges, scrub and woodland edges. It needs an extensive area of untidy, lightly or rarely managed habitat containing its larval host-plant, Common Blackthorn. Where it inhabits climax woodland the adult is rarely seen because it keeps to the tree-tops. In this habitat, such as in Garryland Wood, Galway, it frequents Common Ash trees where it feeds on the aphid ‘honeydew’, secreted by aphids feeding on the leaves. This sticky substance coats the leaves when aphids are in abundance, so the adults do not need to descend to feed on nectar. In years when the aphid secretions are ample, woodland males are rarely observed.
Adults mate early in the day. The rest of the day is mainly spent feeding and basking. It appears to be a very lazy butterfly; it flies infrequently, preferring to walk from one food source to the next. Strong wind does not appear to dislodge them. Males occasionally chase each other, but often they ignore each other and mated females. Later in the flight period, typically from mid-August, females disperse to lay eggs on low-growing Common Blackthorn. This is when most sighting opportunities occur. Even then, females do not advertise their presence. Egg-laying females crawl into the interior of a plant probing the surface of young stems for a suitable point, often at the base of a fork, bud or spine, to place her white egg. Occasionally she will deposit two or even three, but usually a single egg is laid before she flies away to seek another food-plant. When moving to seek new larval food-plants, she will sometimes cross open ground, and fly well above head height, making the butterfly hard to spot. Plants favoured for egg-laying are often young, and are in sheltered and unshaded locations.
The egg has a pitted surface, resembling a golf ball. Although a sharp white, it is not easy to find until leaf fall. Then it comes into its own! It stands out against the dark twigs, even in low light. The eggs are usually placed below 1.5 metres above ground (although sometimes higher; I observed egg-laying three metres above ground in Tipperary). The eggs are laid from mid-August to mid-September and remain unhatched until leaf burst in April. However, eggs remain on the plant after hatching because the larva only bites a whole in the tough shell to emerge from. I have seen eggs remain on a plant for two years, a testament to their durability.
The larvae are mainly green with diagonal white lines. The larva is slug-like in its shape and, like the rather languid adult, sluggish in its movements. In keeping with the adult’s elusiveness, the larva is mainly nocturnal and very hard to find. The pupa too is concealed. It is formed in June or early July, probably in a crack in the soil or beneath leaf litter or within grass tussocks. It is likely that the pupa has an association with ants.
Where the general landscape’s hedges and scrub are lightly managed over time, annual egg surveys pose interesting questions about the breeding requirements of the species. For example, breeding sites can receive fewer eggs over time before these eventually fall out of use. Identifying the reasons for this will add to knowledge of the butterfly’s requirements. Reasons for selection of breeding sites are not easy to determine. In the Burren where tall trees are scarce or absent, the adult feeds low down on hedges containing flowering bramble. While the butterfly breeds on these hedges some adult feeding areas are not used for breeding, even though the larval food-plants and aspect appear suitable.
Last weekend I snatched a couple of hours from an onerous schedule to do a quick egg-hunt at Gortlecka, in the Burren National Park in Clare. On a wonderful mild afternoon I searched a south facing hedge and adjoining patch of scrub where I saw a female lay an egg in August. Within a 20 metre long section of young blackthorn scrub/hedge I found 16 eggs, a couple just 30 cm above the ground. Fifteen eggs were laid at or close to the base of a lateral shoot with one laid slightly further up the side shoot, above three buds. This patch of scrub has developed in the past five years and this is the first time I have found eggs here, although I found eggs on the adjoining hedge in previous years. Despite annual searches over more than a decade I have not found eggs on a west facing hedge very close by, despite seeing females here last August, and in most years from the early 2000’s; however, I have found eggs on west facing scrub elsewhere at Gortlecka. Why it behaves like this is unclear but it is reassuring that the butterfly continues to thrive where I first saw it in the late 1990’s.
Regarding conservation, the species is highly vulnerable to extreme and regular cutting of hedges. While opening up rides in darkening woodland and then allowing plants to re-grow helps the species, annual flailing of hedges is very damaging, as most eggs are laid at the edge of a hedge. In areas where it occurs, rotational cutting should be applied, with large sections, around two-thirds, uncut in any year. It is important to retain patches of young scrub growing a short distance from a hedge or wood edge, as young plants are often favoured by our rarest hairstreak.
Why are many butterfly lovers so taken with this butterfly? Like many obsessions, the reasons for it may be obscure, but the elusiveness of the adult juxtaposed with the visibility of the egg might be something to do with it. So might timing. What else can a lover of butterflies do during the barren, bleak , unforgiving months from November to March? Egg hunts provide a badly needed outlet for pent-up desire, as well as offering an insight into how well the population is performing.
October is, in fact, not renowned for butterflies or moths.
Mild October weather will see some Red Admirals, Small Tortoiseshells, Commas, Speckled Woods, and the very occasional Peacock visiting gardens for over-ripe fruit and hedges for over-ripe berries and late nectar. Painted Lady butterflies can sometimes be found, usually at the coast. Occasional Small Whites and Large Whites will hatch in October instead of over-wintering in their pupae, proving eye-catching at this time of year. In some years a small number of Holly Blue butterflies will show up in warmer parts of the country, such as in Dublin, near the coast, and will be found on Common Ivy, its main food plant at this time of year. You might even stumble on a late Small Copper on a patch of patchily vegetated peat or eroding sand dune, absorbing the thinning autumn sunshine.
Of these, the most reliable butterflies at this time of year are Red Admirals and Small Tortoiseshells, usually flying quite high or basking on a south facing wall.
But all of these butterflies really belong to spring and summer. Autumn is their twilight home, very much an abode of last resort. Now they are no longer wide-ranging and carefree, restricted by diminished nectar and declining temperatures. Autumn is neither their era nor friend. While many of us enjoy the rich colour autumn brings to the landscape, this will be ripped down by November storms. You will wake to see summer’s leafy temple torn down; gone are the golds, russets, rich reds and purples; left are the gnarled bony boughs. And the butterflies are gone too.
Autumn can deceive the nature-lover, and nature. Some plants will produce a second set of flowers. And sow thistles, those tall, plants with showy golden flowers continue to shine, while late Devil’s-bit Scabious blossom, now looking darker blue, lend the illusion of a continuing bounty. The ivy flowers continue to ooze fat globules of sweetness and are heavily frequented by bees and wasps. Struck by this illusion of unending summer, the poet John Keats in his masterpiece “To Autumn” describes how autumn conspires with the sun to
“set budding more, /And still more later flowers for the bees/Until they think warm days will never cease / For Summer has o’er-brimm’d their clammy cells”.
The richly sensuous nature of this imagery, the appeal to sight (budding, flowers, bees) and the tactile sense (warm, clammy) create a rich, reassuring vista in which the seasonal shift is bare perceptible.
Yet winter is on its way, and Keats knew it. He closes his poem with references to the advancing season:
“And the red-breast whistles from a garden-croft/And gathering swallows twitter in the skies”.
Butterflies too must prepare for the cold months. In autumn most Red Admiral and most likely all Painted Lady butterflies move south across the seas, chasing the sun and resources fast fading here. The Peacock and Small Tortoiseshell will stay put, hiding from the cold in cool, dry recesses. These two play the long game, delaying breeding until better days come in the following year. The Large and Small Whites, Speckled Woods, Holly Blues and Small Coppers that emerged late, deceived by the autumn sun perish in the wind and rain but some get the chance to leave eggs behind. These must hatch and develop swiftly to have any chance of adulthood.
But most of our butterflies exist over winter in the least demanding, low-maintenance forms. Some are tucked up in their pupae, others stay in the egg stage while the rest are either small caterpillars or caterpillars that have finished feeding. These survival strategies get them through the lean months, especially November, December, January and February. In years with cold springs, winter survival strategies are maintained until conditions improve. Our butterflies are resilient, well-adapted to our seasons. All they need is good homes.
Unlike our butterflies, there are moths that specialise in flying during October. For some moths, October is their time. Some are beautiful, but rarely seen. The Herald, named for the heraldic appearance, prepare to over-winter as an adult by feeding on ivy flowers and extra-ripe blackberries. The Herald is a well-built long-lived species, which can be found from September to June. This lovely insect will spend the hostile months in your attic, sometimes in large groups. Another autumn beauty is the Merveille du Jour, the freshly hatched moth green and flecked with black. Unlike The Herald, this creature breeds in autumn, leaving its eggs to spend the winter on oak twigs. For its distinctive moths, October has its benefits!
Lullybeg’s Crabtree Reserve continues to produce good numbers of butterflies well into September, despite the often disappointing weather since late July.
Sunday saw some stunning conditions and Red Admirals, many very recently emerged, were observed feeding on Devil’s-bit Scabious, one of Lullybeg’s best nectar sources and certainly the best autumn food source for the reserve’s butterfly, moth, bee and hoverfly populations.
There were significantly fewer Red Admirals than earlier in the month, but this points to migration; at this time of the year, Red Admirals, after feeding up for a few days after emerging, head across the seas to breed further south where temperatures and larval food plants are more suitable. The individuals still present are mainly later emergents and will leave in their turn. However, already their basking behaviour differs from that observed in early September. When direct sunshine was interrupted by a cloudy then, the Red Admirals continued to feed initially, but then left the flower to bask, often on the ground or low down to recover heat lost while feeding during a cloudy interval. Towards the end of the month the butterflies leave the flower shortly after it clouds over to seek cover or to bask higher up, such as on a tree trunk, to catch the light when the sunshine returns, especially in the afternoon when shadows lengthen. Basking by Red Admirals on trees is often observed in late September and October; as the sun’s angle becomes lower, the butterfly basks higher up. Luckily it finds food on trees that contain Common Ivy, a valuable late autumn nectar source. Humble and even unloved it may be, ivy is a banquet for insects flying late in the year. In overcast but mild conditions, Red Admirals are capable of remaining active. Because of this ability it can fly during mild conditions even in mid-winter. The butterfly only needs direct sunshine to maintain activity when air temperatures are cool.
Brimstones were also on the wing, enjoying the Devil’s-bit Scabious nectar in the lovely autumn sunshine. Here the benefits of the lower autumn light can be seen; it passes through the golden male Brimstone’s wings, showing an intense purity, like holding up a jar of honey to view with the sun shining through it. In fact, the colour of the Brimstone appears liquid, a fluid intensity that one almost expects to see leak golden light! In short, a photograph of a back-lit Brimstone is a must-have!
Another busy butterfly is the Small Tortoiseshell. Like the Brimstone he is feeding in advance of over-wintering in its adult incarnation; unlike the Brimstone which seeks a leafy sanctuary such as that afforded by Common Ivy, Common Holy and bramble, it seeks dark, often pitch black winter quarters. The Brimstone is more vulnerable to paralysis when the sun stops shining. It very swiftly loses the ability to fly when direct sunshine is terminated while the Small Tortoiseshell can fly in dull but mild conditions. This explains the longer flight season of the Small Tortoiseshell in Ireland, and why it is found throughout the country while the Brimstone does not occur in north Leinster or Ulster.
Speckled Woods were about in fair numbers last Sunday. The autumn brood of this woodland and hedgerow butterfly, whose numbers peak around mid-September, is often very large and for a week or two it seems that summer is not over at all! Sadly, this boom passes quickly, and numbers are now thinning out…
A few Green-veined Whites, representing a partial third brood put in an appearance. One male Green-veined White tormented a male Brimstone. The rather annoyed Brimstone did his best to shake off the unwelcome attention by flying erratically, and by gaining height; Green-veined Whites rarely fly at tree-top level. This one did. The Brimstone then tumbled downwards pursued by his amorous pest until I netted both and released one, then the other. The likely end to this scenario was avian attack and I was in an interfering mood. However, the male Green-veined White was fairly exhausted by his efforts, and needed a rest to bask and recover lost body heat. Both protagonists are pictured here, after the incident.
Butterfly Conservation Ireland attempted to contact the National Parks and Wildlife personnel responsible for the region in which Killeglan Grasslands is located to check if the site was damaged or about to be damaged. This issue is referred to in a previous post.
After several phone calls and over a week after our concerns were relayed, we were contacted and a site visit was made by the person responsible for checking on designated sites in that area. We were told that the damage done bordering the site took place some (unspecified )time ago and that the piling up of stone on the SAC was carried out several years ago and is that noted in the site description published on the National Parks and Wildlife website.
Butterfly Conservation Ireland expressed its concern to the official about the failure to respond to our message and about the time taken to deal with the issue. The National Parks and Wildlife staff have the crucial role of monitoring our designated sites which contain our best natural habitats. The delay in responding might see irreparable damage caused.
We hope that our special places receive the protection they need, and that the National Parks and Wildlife Service is given the resources, management and support needed. Above all, we will continue to press for the fullest commitment to nature conservation by the staff of the organisation.
Enormous destruction of Ireland’s natural heritage took place especially from the 1970’s. Unless we show we really are serious about defending remaining patches, we will have nothing left to protect.
August has drained into September. September so far refuses to redeem its predecessor, dribbling feebly on some days while squally showers and sharp bursts of sheeting rain dominate others along with murky skies and rapidly depreciating daylight. September has not shone but the scarlet and black Red Admiral is everywhere, and building its forces still. This most handsome migrant has been advancing since April and is now erupting, commandeering nectar supplies for the next phase of its campaign.
A breeder on the Stinging Nettle, it has been quietly about its business all summer and is now showing its colours. Over 80 were counted at Lullybeg today, almost all of them in picture-perfect in their regimental dress uniforms. While not intricately patterned and multi-coloured like the Peacock, the Red Admiral has a smart costume, arrestingly sharp in appearance. Most if not all of the Red Admirals I saw today will feed a few days more before heading south across the Irish Sea or St George’s Channel to invade, or seek refuge in warmer climes perhaps in the south of England or the continent. There some of our Red Admirals might settle to breed while others may push further southwards before finding the conditions suitable for their offspring.
The very southern fringes of Spain and France or even North Africa might be the ultimate destination of Ireland’s autumn admirals. There, during the warm, sunny conditions along with seasonal rain will allow for breeding into next spring when dry, hot conditions burn off nettles and return our admirals to us.
In recent times, though, some admirals, it seems, have decided against the hazardous overseas migration. This phenomenon was first noticed in this part of the world near the south coast of England, around the year 2000. Some now remain in Ireland, but unlike the brave but misguided Barn Swallow in The Happy Prince, some of these have survived. Clinging on in mild spots along sheltered coastal niches, Red Admirals have been found, breeding through the winter. Howth Head in North Dublin has seen this activity. Here the strategy has been for adults to breed in late autumn and early winter and for the immature stages to develop slowly in the cool conditions from mid-winter to late spring. The coastal sighting of Red Admirals elsewhere in Ireland and England late and early in the year hint at resilient breeders or stranded butterflies.
There is no doubt, though, that most of the admirals feeding now will leave our shores. If the number of Red Admirals in our fields, woods and gardens are as high as those elsewhere in Northern Europe, there will surely be enormous numbers reaching southern breeding grounds from early October. A candidate for Butterfly of the Year 2017?
Heritage Week, with an emphasis on natural heritage concludes today. Whales, bugs, badgers, bees, butterflies, birds and a wonderful array of wild places in which these creatures have their homes were showcased and the weather for some of the week and much of the country was, at least, serviceable.
It is comforting to see wild creatures behaving as they should in their habitats but grave threats to these wild havens exist. Some are in serious peril.
Under the European Union Habitats’ Directive, prime sites in Ireland and throughout the European Union were selected and designated as Special Areas of Conservation (SAC’s). These areas are legally protected under national and European Union law. Landowners who wish to carry out specific actions, known as “notifiable actions” must obtain written consent from the Minister of the Environment. Permission is not usually given for actions that would damage a site, not to mention actions that lead to a site’s destruction. The body charged with the role of protecting these precious areas is The National Parks and Wildlife Service (NPWS), under the Minister for Arts, Heritage and the Gaeltacht.
However, it appears that the National Parks and Wildlife Service is weakly led, ineffective and unresponsive. A site synopsis for each SAC is published on the NPWS website, and these do not inspire confidence that the will to act against destroyers of our heritage exists. Take the beautiful Killeglan grasslands in Roscommon, which lies around 9.5 km north of Ballinasloe alongside the R357. This stunning example of limestone grassland is a mini-Burren, in Roscommon. When I encountered the site for the first time recently, I was mesmerised to find it; why is this gem unpublicised? There is no signage, no place name, nothing to indicate its special status. My feeling is that it should be celebrated as the “Roscommon Burren”, and a marked walking route and perhaps a small interpretive facility added to highlight its features, and the characteristics of other designated sites in the vicinity.
The glow of purples and deep pinks, the more muted colours of late summer are preceded here by a wealth of colour as this is a rich site for orchids, especially noted for the nationally rare Green-winged Orchid. Unsurprisingly, it’s a wonderful butterfly site too, with a broad range of notable species, including Brimstone, Dingy Skipper, Silver-washed Fritillary, Dark Green Fritillary, Marsh Fritillary, Wall Brown and Grayling.
A closer look at the site and its surroundings provide evidence of threats to the site’s existence. Large-scale modification of the landscape has taken place around the site; a local resident showed me where habitat to the east of the R357 identical to the existing area was destroyed by bulldozers and importation of topsoil, which, to judge from images from googlemaps, took place in 2009. Damage was done to the western edge of the site (whether this is within the SAC boundary is unclear) since 2008, when part of the field was leveled and stone was bulldozed into a heap, piled up like debris from a slum clearance. Adding to my alarm was the fact that smaller stone on the unaffected area has been placed in piles scattered throughout the site. Is this a precursor to an all-out attack?
NPWS are aware of the threat. A sentence from the site synopsis on the NPWS website states:
The grasslands have been improved in the past and limestone boulders have been cleared and placed in heaps scattered throughout the site. The site is divided into a number of small field systems that are defined by dry stone walls. Neighbouring lands have recently been cleared of boulders and shattered pavement, and have been re-seeded and heavily fertilised. Reclamation within the site would pose a significant threat to the conservation interest of the grassland.
Seeking clarification and concerned by what I saw, I attempted to contact staff assigned to the North Midlands Region. I rang all five phone numbers I obtained from the NPWS website; no response. Three of these numbers are clearly no longer in use. I then rang two mobile numbers I obtained from NPWS Head Office; no answer; left a message; still no response. I rang three further numbers on the website for another region; no response. Finally, phone call number 11 got an answer! I got through to the store manager in Wicklow! Over a week later, I received a call from an NPWS official from a different district.
This is a disturbing situation . Our heritage deserves the best protection it can get. If the site was being bull-dozed while I waited for a response, would there be any habitat left by the time those whose duty it is to protect our natural environment reacted? Will Killeglan’s limestone grassland with its fabulous mixture of flowers and butterflies, its Pine Martens, Hares and wilderness, which has been there for perhaps thousands of years, still be there, safe from JCB’s and topsoil, in one hundred or even in ten years’ time?
For all our members and friends who record the butterflies in your garden for Butterfly Conservation Ireland’s recording scheme, this is a reminder to keep a keen watch on what’s happening in your garden.
The records we need are the date/s you first see the butterfly in each three month period (March-May, June-August, September-November) At the end of the season you record the peak number and date/s this peak was reached for the entire recording period. The completed form, with any comments is returned to: Butterfly Conservation Ireland, Pagestown, Maynooth, County Kildare. A report based on the surveys will appear in our annual report posted in hard copy and on-line.
The weather has been very erratic this month with some lovely conditions such as the warm sunshine and light breezes of Sunday August 13th and the heavy rain the next day. When there is a sunny window in the weather, especially sunshine following a day or several days of rain, I urge you to get out in your garden and observe what’s happening. Butterflies often show a burst of activity when sunny weather follows a period of heavy rain, rather like a burst of birdsong in spring when a cloudburst exhausts its downpour.
On Sunday morning (August 13th) I spent time in the garden, relaxing among my tall, now rather unruly meadow dominated right now by Common Knapweed. This multi-stemmed, multi-flowering native perennial is a magnet for nectar-loving insects and later, for seed-eating birds. It has been in flower since June but is peaking now, just when the peak butterfly populations are in play. Timing is everything with butterflies. The first Holly Blue Celastrina argiolus to visit me this year showed up at the end of May, too late to breed on my holly plants, grown specially for her. But she is fussy, only laying on holly in flower, not on plants already in berry. The caterpillars can only tackle very young, tender berries so the mother selects the flower as egg-site. How she knows this I am unsure, but chemical receptors on her feet, palps, antennae and thorax might be able to test for the presence of the nutrients needed. She sometimes gets it wrong though, and deposits eggs on the flowers on male holly, which will never produce a berry.
My visitor was in luck. The hollies were off the menu, but my Alder Buckthorns were in flower and soon she used this unusual food plant. The choice paid off, and on Sunday freshly emerged Holly Blues fluttered around my hedges, especially around an old Common Hawthorn, crowned with dense flowering Common Ivy, the species main late summer and autumn food plant. A result, I tell myself!
The Peacock’s Inachis io breeding requirements and life cycle is less complicated. It has one brood per year and one larval food plant, Common Nettle. A nettle patch growing in a warm, unshaded sheltered recess typically in a clearing/track in a wood, at the edge of a wood or against a south facing hedge is used. These multi-coloured emblems of August are adorning my knapweeds, adding glamour to my garden. (Are they rare? I’ve been asked. Surely something so gaudy must be scarce). I counted 16 on Sunday! This for me is three short of my Peacock record of a couple of years ago. Will I equal or even surpass 19? We’ll see. At the moment, they look very content, moving gently from bloom to bloom, gorgeous with wings fully extended, black shark fin-shaped undersides when heat dictates wing closure.
The whites are a sharp counterpoint to the multicoloured Peacock, the Large Whites Pieris brassicae are enjoying a boom this summer. The sexes look similar but the female has two prominent parallel black spots on the upper surface of her forewings which are clear white in the male. These are very skittish, easily disturbed and disruptive, chasing any other white or pale butterfly as they check the mating possibilities. In my garden they are just re-fueling, but a neighbour grows nasturtiums, one of the larval food plants. The Small Whites Artogeia rapae are about too. These look like smaller versions of Large White, but taxonomists have proposed that these two “cabbage whites” are not as closely related as previously thought, mainly due to differences in chromosome number, egg-laying behaviour (solitary in Small White, gregarious in Large White) and larval survival strategy (reflected in morphology (larvae of Small White and close relatives are green and rely on camouflage; Large White larvae are black, white, yellow and conspicuous, relying on display of warning colours), behaviour (solitary in Small White) and biochemistry (Large White larvae are strongly distasteful, arising from a concentration of mustard oils containing suphur assimilated from the larval food plant)). These differences are reflected in the reassignment of Small White and Green-veined White from the genus Pieris to Artogeia. However, none of this taxonomic refinement/redefinition bothers the Large White, which inspects and is inspected by Small Whites as males seek mates.
The tiny gem that is the Small Copper Lycaena phlaeas is my garden favourite. A male has taken up residence, and has seen off another male. He carries out regular inspections of the garden, surveying his kingdom from specific vantage points, like a Medieval king using his castles as strongholds from which to exert his authority. Any upstart is assaulted and driven off. While I can hardly blame him, his activities lower my Small Copper count!
A rather lazy Red Admiral is hanging around at the moment, but he is so bedraggled as to be barely there, yet he still insists on helping himself to the buddleia. There will be fresh specimens later in the season and, like the Peacock, I never tire of taking photos of this handsome yet familiar butterfly.
No previous experience of butterfly gardening prepared me for the appearance of the endangered Wall Brown. This most attractive member of the brown family of butterflies has declined catastrophically since the mid-1980’s (heavier rainfall? change from hay to silage? increased chemical inputs?). A pristine female visited my garden, sipped on a knapweed, basked and fled. I have never seen this species in an Irish garden, so am delighted that I was there to see her. I just hope she finds a mate and settles in the area!
All these photographs were taken in gardens. Keep watching!