Butterfly Conservation Ireland

Saturday 1^st December was officially the first day of winter. It began mistily mild before clearing to a drier grey which later dissolved into a light rain as heavier cloud darkened the afternoon before petered out into twilight disconcertingly early. At least our winter moths liked the conditions which were accommodatingly mild allowing furry, thick-set December Moths and lightly built Winter Moths to gather on walls close to outdoor lights. While these moths are thin fare for butterfly and moth lovers, we are at least reminded that we still have signs of life, little pick-me-ups for the rather bleak weeks and months to come.

December Moth, which flies from November to January.

But this is not the time for lethargy. Winter is time for actions of a different kind. Now is the period for preparing sites for the coming season. Targets need to be met, be it to clear dense bramble and thorn scrub invading a flowery track through woodland, opening a glade in dense woodland to allow flowers bloom or to reveal a gorgeous female Common Holly glowing green and red in dimming December light, removing non-native trees or shrubs which threaten to overwhelm a native woodland or to remove selected trees to thin out dense woods to let light in to make the violets attractive to Silver-washed Fritillary butterflies.

Some of these actions are needed on the banks of the Royal Canal near Mullingar. Butterfly Conservation Ireland members along with the Westmeath Branch of BridWatch Ireland joined the effort to restore habitats with the Baltrasna Boreen Biodiversity Group, led by Lesley Whiteside. The high bank has a range of habitats, including native ash woodland, scrub consisting of willow, Common Holly, Guelder Rose, Common Hawthorn, Common Blackthorn and calcareous grassland containing Kidney Vetch, Common Bird’s-foot-trefoil and Autumn Gentian.

The steep site has four parallel paths, each quite different, offering different experiences; an encounter with badgers on one, Common Blues dancing around yellow blooms on another, water birds on a third and a brisk walk on the gravelled towpath on the fourth path. The site was grazed until the early 1990s but since it has developed woodland out of which paths and clearings are being carved to develop new habitats and increase biodiversity.

To this end, overhanging branches were tackled along with dense scrub and a sinister invasion by cotoneaster, a non-native which causes great damage by carpeting good limestone grassland. Extensive clearing of selected dense scrub was achieved. By allowing in light the flowers will be able to blossom and the bees and butterfly species will be able to avail of their nourishment. It was a demanding job but much ‘heavy lifting’ is now done, making it easier to deal with younger scrub. We are looking forward to our outing there next spring/summer to see how the flora and butterflies respond.

Finally, there must be many opportunities for biodiversity-conscious local groups to get involved in such projects. With permission from landowners, some planning and research much can be achieved, for people and nature. A special thanks to the Baltrasna Boreen Biodiversity Group for looking after their butterflies so well in this intriguing spot in Westmeath.

Photographs ©J.Harding.

 

Lullybeg management day went ahead on Saturday 10th November. It was a wet start, with light rain for a time which eventually petered out. Later the sun broke through and we had quite pleasant conditions for our work.

We weeded a track on part of the butterfly transect where numerous birch seedling had moved in. These were pulled up by hand. A mattock was used to uproot three invasive willows, leaving the area open and ready to continue to receive full sun, flowers and butterflies in 2019.

Later we cut and piled scrub on the Lullymore to Lullybeg corridor. We created some scalloped edges to create additional warmth and shelter, providing the perfect warm-up zones for butterflies, moths and dragonflies.

The cattle continue to feed on the reserve and these have settled well. They are certainly disturbing the denser areas dominated by Purple Moor-grass, great for maintaining the flora on the site.

We took a break for lunch and watched the cattle which appeared very much in tune with their new surroundings. It gave a restful feeling to see them at ease, and a great feeling of optimism for the coming season’s butterfly populations.

Thanks to all who helped out, and we look forward to seeing you again in February 2019.

The summer of 2018 was warm, dry and created excellent conditions for vegetation growth, especially as the peat soil retained some moisture.

Now it is time to remove the heavy grassland vegetation,  reduce the density of the tuft-forming Purple Mor-grass, create soil disturbance to create warm, bare patches for germination of new flowers and provide good basking spots for adult butterflies and warm breeding sites for caterpillars and check the re-growth on coppiced willow. In short, it is time to introduce cattle to enhance the habitats on Lullybeg’s Crabtree Reserve.

The work on preparing the site for grazing took place, happily, in dry sunny conditions on Thursday 1st November. Ten hungry cattle were introduced and these explored the reserve before settling down to a good meal. Cattle are selective feeders, ideal for creating an uneven patchwork of sward heights which is perfect for all of Lullybeg’s grassland moths and butterflies.  Removal of dense vegetation keeps soil fertility levels low, allowing the flora, such as the range of orchids present here, to thrive. Without the intervention of livestock or regular disturbance by heavy machinery, dense vegetation dominated by ranker grasses develops, choking less robust plants and cooling the soil and herb layer, making breeding conditions less suitable or even impossible.  Just to show how dense grassland vegetation affects one butterfly, let us consider the habitat required by the Dingy Skipper.

This intricately patterned little butterfly (see photo below), rated as near threatened in Ireland lays its eggs on Common Bird’s-foot-trefoil, a low-growing straggling perennial that dies back in autumn and re-sprouts in April. It must be unshaded for the Dingy Skipper to breed on it. The plant must grow in a warm area, usually with some shelter which means it needs to grow among dry dead vegetation or grow close to bare soil or rock that heats up in direct sunlight in order to be suitable for the butterfly. Plants shaded by tall grass or scrub are not used. Cattle grazing will pare back dense grasses and poaching will disturb the soil around the plants making germination of new foodplants possible and ensuring the conditions needed remain suitable. Common Bird’s-foot-trefoil is also used as a nectar source by the Dingy Skipper and by a number of other butterflies but butterflies rarely take nectar from plants in shadow. By grazing the vegetation, the cattle help to create open conditions to assist this lovely flower to thrive, ensuring that butterflies that use the plant for breeding and nectar, including the Common Blue and Cryptic Wood White, and day-flying moths such as the Narrow-bordered Bee Hawkmoth, Burnet Companion and Mother Shipton, will continue to prosper.

We know from post-management monitoring in previous years that the Dingy Skipper breeds in areas containing the foodplant that were cleared of encroaching vegetation the previous winter. The Dingy Skipper, along with many butterflies, are quick to exploit new opportunities. We look forward to next spring to see the fruits of our work!

Our thanks and appreciation go to our supporters and to Philip Doyle and his staff.

The weather forecast for Saturday, November 3rd 2018 is for high winds and heavy rain. We will defer the conservation management event planned to take place on November 3rd until the following weekend. The site management day will go ahead on Saturday, November 10th provided the weather is suitable.

We apologise for any inconvenience and look forward to seeing you soon.

October 2018 continues mild, gentle and pleasant, easing the transition from the scorching summer to whatever winter holds. Whatever this winter throws at us, October is producing really impressive moth numbers. Among the selection being trapped are the following autumn species. These are subtly coloured, reflecting the earthy tone of the season. Late butterflies continue to be seen, especially Red Admiral, Small Tortoiseshell and Speckled Wood but there might be a surprise species flying, so keep looking.

 

 

A beautiful sunny day on Sunday 14th October encouraged butterflies to enjoy the heat. A calm day allowed heat to build, enticing over-wintering butterflies to venture out. A male Brimstone, some Small Tortoiseshells and a Peacock brightened this mid-autumn day. These were joined by two female Small Coppers, a Red Admiral and a brace of Speckled Woods. Ruddy Darters dragonflies were everywhere, grasshoppers chirruped and it felt like August!

Leaving to go home was hard but a bright orange neon glow on glossy ivy leaves high up on a hedge at Lullymore stopped the car. A lovely Comma! Will it breed in the area? There is an abundance of breeding habitat and overwintering sites in the area. It was still there today (Monday, October 15th) and seems to be making itself comfortable sipping ivy nectar.  Welcome to west Kildare!

The Comma butterfly was first sighted in Ireland in the late 1990s but it was not until about the second decade of this century that regular sightings were being reported. Breeding was first confirmed in a wood in Carlow in May 2014. Since then the butterfly has been reported, usually as single individuals, in many areas in the south-east. Its spread is expected to continue, and it joins the 23 other butterfly species recorded in Lullymore/Lullybeg in 2018.

For many lovers of nature, especially for those of us who enjoy butterflies, autumn is unwelcome.  We see the signs of decline everywhere and we fear the season to follow.  This is not a recent feeling.  Sonnet 73, written by William Shakespeare sometime between 1592 and 1598, opens with this quatrain:

That time of year thou may’st in me behold
When yellow leaves, or none, or few, do hang
Upon those boughs which shake against the cold,
Bare ruin’d choirs, where late the sweet birds sang.

Shakespeare wrote about late autumn, which he associates with decay and imminent death. The trees with few or no leaves are now without birdsong. He may be referring to the by then ruined monastic settlements, the closure of which was ordered by Henry VIII following his decision to cut ties with the pope and confiscate church property (1536-1540). Seen in the light of this interpretation, the ruined choirs are the roofless remains of monasteries, the sweet birds the choirs of singing monks. Whichever interpretation is accepted, and both are valid, it is inescapable that the bard was referencing the inevitable march towards decay symbolised by autumn. The cold winds will soon rip whichever leaves cling to claw-like twigs and the landscape settles into a sullen palate, empty of vibrancy.

Yet poets do not always portray autumn negatively. Writing on September 19th 1819 William Wordsworth eulogised the season in Ode to Autumn.  Wordsworth, a great nature lover, saw autumn as a time of plenty. The sun will continue 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-brimmed their clammy cells.

This wonderful feeling of neverending abundance and the idea of nature’s opulence has far greater appeal than Shakespeare’s bleak vision of loss and decay. Indeed,  following one of the greatest summers in our lifetime, surely some optimism is justified.  We continue to see Comma butterflies in Carlow and Kilkenny, Small Coppers in Meath and Large Whites, Red Admirals, Peacocks, Small Tortoiseshells and Speckled Woods in Donegal. These sightings, albeit of just a few individuals, allow us to cling on to summer, just!

By contrast, good numbers of moths continue to appear in light traps, some even in spectacular numbers. On October 3rd I counted 177 moths of which 138 were Beaded Chestnuts. This count on a single night exceeds the totals I had for the species throughout its flight period for each of the three years 2015-2017.  A count of over 3,000 moths in my garden for the 2018 recording season easily exceeds these previous years’ totals, strongly suggesting that the moths, like our butterflies, greatly benefited from the heat of the summer.

Prolonged heat allows butterflies and moths to move around the landscape to find food, mates and breeding sites. It also allows some species that have already laid their eggs but which can mature a second or even a third batch of eggs to do so. Warmth also helps the eggs, larvae and pupae to develop faster, lessening the time available for predators to eat them. Prolonged warmth will allow time for species that are capable of producing more than one set of adults in a flight season to produce more generations to fly within the same year.  This may result in a succession of generations which may even overlap so that the species in on the wing for much longer than it will be in a cooler year.  This overlapping of broods was observed in 2018 in the Small Copper. In addition to the heat during May, June and July, the low rainfall levels from May to September inclusive also helped, as wet conditions have been shown to cause damage to the early stages, including, expectedly, the pupal stage.

In many ways 2018 was exceptional. We had an unusually long winter, a bitterly cold, snowy March, a dull, very wet April (remember the fodder crisis?) followed by prolonged hot, dry weather over the following three months giving us the joint warmest summer on record. The dry conditions have persisted into October.  Butterflies certainly flourished, and, as recent research indicates, (see https://butterflyconservation.ie/wp/2017/12/08/winter-cold-a-benefit-for-butterflies/ ) cold winters do not harm most butterfly species.

When the cold weather takes its grip, remember the glory of the summer of 2018 and bask in your memory of its splendour. As Wordsworth wrote in Tintern Abbey, these happy memories provide spiritual, emotional and psychological sustenance for the lean times ahead!

All photographs © copyright J. Harding 2018.

 

Shadows are lengthening,  temperatures falling and storms Ali and Bronagh dishevelled and drenched the landscape. Butterflies continue to fly but numbers are inevitably falling.

Summer and autumn flowers are fading fast with many species now in seed to feed Goldfinches and other seed-eaters. There is still floral nourishment available with  Common Ivy flowers sticky with nectar and thronging with wasps, flies and some butterflies.  Late bramble and Common Knapweed flowers offer food, while some repeat flowering by Common Dandelion is a cheering sight for late butterflies.

Butterfly sightings continue to be made but records are diminishing. There is a tendency to think that butterflies have vanished until next spring because the free-flying adults are harder and eventually almost impossible to find.

Butterflies continue, mainly in immature forms. Many butterfly larvae are extremely difficult to find in the wild, and a number of species have not been found or recorded in Ireland as wild caterpillars or pupae. I know of just two people who have found wild Purple Hairstreak larvae, and no record of anyone finding Hedge Brown larvae or Wood White larvae, to mention just three species.  This is not surprising. I have taken 20 minutes to locate a Wood White larvae I knew to be present on cut food plant in captivity. Its camouflage is superb. Not only is the larva the same green shade as the leaves and stems of the plant, but it also aligns itself to resemble a leaflet or part of a stem. It is assisted in its concealment by its highly sedentary manner.  The Wood White caterpillar, which leads a solitary life, is feeding now and will pupate late in September or early October. The butterfly will emerge, typically, in May but if there is a cold spring a June/July emergence can occur.

One butterfly that will emerge as an adult this year from the immature forms now present is the handsome Red Admiral. There are many final stage caterpillars and pupae, tented in nettle leaves, out there now. Some adults are emerging now, a process that will continue well into October. The larvae are interesting in that they occur in a range of colour forms, even in the same nettle bed. The colour matters little, as larvae are hidden. This is one of the easiest solitary larvae to find, with droppings often found accumulated in a large leaf below the tented enclosure. Opening the tent will reveal a larva curled in the shape of the number 6. The pupa is a light brown with golden metallic markings. The adult is stunning, especially when seen on a bunch of juicy blackberries or feeding on ivy among the glossy foliage. The adult will hang about for a few days before breeding, or more likely at this time of the year, before heading south to the continent to breed.

The Wall Brown larva is feeding now but finding it is a serious challenge. Features that may help is that it feeds in daylight and basks on bare soil near adjoining grass. The older larva is green with a bluish tint. It loves Red Fescue grass growing in sparse clumps on well-drained soil. Differential growth rates of same-age larvae is a feature of second-generation Wall larvae, with remarkable size variations evident. The fastest growers will sometimes pupate and produce butterflies in October while siblings will take to the air next April or May.  Whether October adults breed successfully in Ireland is not known. It is suspected that resultant larvae may be too small to survive the winter.

The Small Heath’s tiny larva is feeding on the tips of finer grass blades. It feeds during sunshine. It is polymorphic, with green, yellow and reddish-brown forms. This larva is very slow-growing until late spring when growth suddenly accelerates. The first butterflies can appear at the beginning of May given a warm, sunny spring. Generally, adults appear later in May and fly throughout June and much of July. Occasionally late butterflies will be seen in late August and September.

While the larva might be seen as the unglamorous stage in the life-cycle, it is extremely interesting. It is the animal’s growth phase and is sensitive to changes in daylight length, temperature, moisture, the nutrient content of the food-plant, the character of its habitat, changes in the habitat and a range of other factors, depending on the species.  The interaction between the larva and elements in the environment, such as the relationship between some Lycaenid larvae and ants makes the study of caterpillars especially intriguing.  It is the requirements of the larva that often influences whether the species is widespread or highly localised. Finally, in the cooler months of autumn when adults are scarce, larvae offer the butterfly lover a challenge and interest.

Photographs © J.Harding 2018.

The great summer weather of 2018 is over but its benefits, it appears, are still being observed. The Small Copper butterfly seems to have produced three generations and a fourth is still possible!

While butterflies being day-flying are easier to monitor, the results of light trapping for moths indicate that some moths are doing well. From the Garden Moth Scheme which covers all regions of Britain and the island of Ireland as one region comes news of very high figures for some species. One recorder had 356 and 131 Setaceous Hebrew Character moths in his two 15W Heath traps. While only 22 gardens in the Republic of Ireland are part of the Garden Moth Scheme these are trapped on over 90%  (97% in May and June 2018) of the nights when trapping is to take place. This high level gives credibility to the results.  For 9 out of the 12 regions in the British Isles, the Heart and Dart moth was the most numerous garden moth on average for May and June 2018. (Scotland and North-east England (Hebrew Character) and the Channel Islands (Diamond-back moth) are the exceptions).

We are now looking forward to seeing how the autumn species perform, and last Friday night saw my first record of the Beaded Chestnut,  a moth that variable in appearance and often quite numerous during its flight period. The appearance of this moth is one of the signals that the autumnal moth species are about to appear. Other moths which occur now include the Setaceous Hebrew Character, a distinctively marked species whose larvae are found on Common Nettle and two more colourful species, Frosted Orange and Pink-barred Sallow. The Frosted Orange larva feeds on thistles leading one to expect it to be far more numerous than it is. In fact, it is recorded in low numbers, and cannot be assumed to appear in gardens every year. Its ginger peppering,  yellow oval markings and brown band means it is attractive and unmistakable.

The Pink-barred Sallow is another pretty species. It shows a broad pink band across canary yellow forewings as its prominent marking with pink mottling above and below the band with the forewing edge pinked out in pink. While it occurs more frequently than the Frosted Orange, small numbers are the norm in my garden. Willows and poplars are the caterpillar’s food plants.

In good habitats, some night-flying moths can sometimes be seen during the day. These are usually observed in tall flower-rich grassland in warm, overcast weather. It provides a rare opportunity to see some species that otherwise can only be attracted to light traps. Like the butterflies, these moths will be found feeding on flowers, especially Common Knapweed, Common Ragwort and Devil’s-bit Scabious. The Silver Y moth flies during the day and night and is very fond of nectar, and will be seen with its typically swift buzzing flight at flowers, fluttering while taking nectar.

To encourage moths to breed in your garden, Grey Willow Salix cinerea and Downy Birch Betula pubescens,  native oaks Quercus robur and Quercus petraea, Common Hazel Corylus avellana, Common Blackthorn Prunus spinosa, Common Hawthorn Crataegus monogyna and Common Nettle Urtica dioica are strongly recommended. Planting a species-rich hedge consisting of these tree species might be used to build a habitat in a smaller garden. A large garden allows room for some trees to develop without cutting and this may be more fruitful as some butterfly and moths need tall trees. A garden such as that shown below can be developed to resemble a woodland clearing, with trees, scrub and or hedging surrounding a grassy area containing native flowers. This offers food, shelter and warmth, creating ideal breeding conditions for many moths and butterflies. And a life-filled, exciting place for you, too.

Photographs © J. Harding 2018.

September 2018 opened with sunny days and warm, still nights, ideal for diurnal and nocturnal Lepidoptera. Numbers are still high but the number of species on the wing is falling as we move into autumn. The moth catch in my garden on August 31st consisted of moths that are typically found mainly in summer although many of these were worn. An extraordinary number, for me, was 222 Square-spot Rustic moths. Never have I seen one moth species in such high numbers on a single night. The high number is most likely the result of a great summer. By August  31st 2017, I recorded 1,502  moths in 21 trapping sessions running from March. By August 31st 2018 I recorded 2,358 moths in 22 trapping sessions.  The increase is probably related to the much warmer conditions experienced during the late spring and for most of the summer this year. The benefits of larger numbers of moths are enjoyed by our bat and bird populations. I am thinking of the 34 Common Pipistrelle Bats and the 40 or so Brown Long-eared Bats that have occupied my attic for much of the summer.

Unfortunately for day flying butterflies, my garden Robin and Wren are keenly aware of the butterflies available. In particular, the birds are snapping up two species, the Small Tortoiseshell and Peacock.  The speed with which a Robin attacks is impressive and while it often seizes the outer part of a forewing instead of the head,  cumulative wing damage reduces flight proficiency and increases the chance of capture.  One Small Tortoiseshell was found dead with no sign of injury. Was it stung by a wasp?  The dramas are compelling to watch and speculate on, but concentrations of prey must lead to high predator activity and high mortality. However, in the case of the fiercely territorial Robin,  high availability of butterflies does not lead to a higher number of Robins to prey on them. Furthermore, some butterflies seem to evade birds. From my observation, the birds in my garden either ignore or cannot catch the Painted Lady and Small Copper!

On September 5th a new Small Copper appeared in the garden, dazzlingly copper in the sharpening late afternoon sunlight. The veteran who has been in command of the perch post on a tall ragwort for most of August encountered the new male and battered him away. The new boy must wait his turn! In the evenings I check the shed to count roosting Peacocks and Small Tortoiseshells. The door is left ajar for them and I hope they decide to pass the winter there.  Sometimes the Robin goes into the shed too but perhaps the bird has not located the butterflies yet. When the warmth is gone for 2018, the shed door will be shut and the butterflies will be beyond his beak until they depart in spring.

Butterfly numbers in gardens appear to be up on last year and they are abundant in other habitats too. While there may not be as many Painted Lady butterflies this year numbers are quite high. Quite often a good year for this butterfly such as 2017 is followed by much smaller numbers the following year but this has not been the case in 2018 on sites I visit or further afield. From Northern Ireland comes a figure of over 100 seen by Ian Rippey on the County Down coast on August 29th. Recent records suggest that these powerful migrants are more numerous than adult Red Admirals at the moment but there are many Red Admiral larvae still developing, suggesting a good flight of the species later in September and October.

There are still Large Whites, Small Whites and Green-veined Whites around but numbers of these are declining as the season nears a close, but where it occurs, the Brimstone, which overwinters as an adult, is quite numerous.  On Saturday, September  1st I saw around 30 of these lovely butterflies apparently hanging suspended on flowers on a cutaway bog in the glorious sunshine. The Common Blue and Holly Blue still fly, as does the Small Copper while in the Burren there may still be some Brown Hairstreaks around.  I saw two late Silver-washed Fritillaries on September 1st and one the following day, all males. Speckled Woods are jinking around hedges in good numbers in many areas, and their numbers often peak in mid-September in parts of the west and the Midlands. This butterfly can sometimes extend into early November. Along the west coast newly emerged Meadow Browns confuse observers from the east of Ireland who are accustomed to seeing this butterfly virtually disappear there by mid-August. In some years Clouded Yellow butterflies arrive in small numbers in September and October, giving a final flourish to the butterfly flight season.

We often enjoy beautiful September weather and if so, some short-lived butterflies may live longer, butterflies that over-winter as adults may fly longer and some species may even fit in a partial late generation. Ireland may also get some late migrants.  At such times of plenty, we can be persuaded that summer is still with us, and will continue to beam warmly on us. But enjoy the butterflies. We know the cold will banish them soon!

While the comparative analysis of the figures for garden butterflies will be published later, in the Annual Report 2018, it is evident that most species are present in higher numbers in many gardens than in 2017. If you would like to take part in our garden butterfly survey, the details and survey form can be found here:  https://butterflyconservation.ie/wp/butterflies/gardening-for-butterflies/

All photographs © J.Harding 2018.