From Junior Infant to Senior Citizen: How the world will look for our Five-year-Olds

Cast your imagination back 125,000 years. The climate then was as hot as it has been in the past decade. Where Trafalgar Square stands today, alligators, hippopotami, and lions roamed the British savannas while elephants grazed the banks of the Thames. Today,  Sir Edwin Landseer’s bronze lions guarding Nelson’s column grandly survey the Square where the wildlife consists mundanely of feral pigeons.

Imaginative indulgence conjures dreams of restoration ecology, beloved by hankerers for the recovery of ecosystems deficient in parts of the puzzle. In Ireland, such projects are usually concerned with iconic apex predators, such as the Grey Wolf, Red Kite, White-tailed Sea Eagle, and Golden Eagle. The latter three have been introduced to Ireland while the Grey Wolf is busy recovering lost territory throughout western Europe, under its own steam, but benefiting from the ban on poisoning and hunting that brought the animal to the edge of oblivion in most of Europe in the late 1970s.

But clocks are not easily turned back, and as the Covid pandemic demonstrated, we are not in control. The greater powers, the wrath of whom we have provoked, are in the ascendant. We are reactors, employing a scattergun approach to problem-solving that Manchester United’s transfer negotiator John Murtough would recognise, but be embarrassed by.

Our vulnerability to greater power than our meagre selves was spelled out to the cabinet committee on the environment and climate change in early May 2022 by Professor Peter Thorne, a lead author on the Fifth Assessment Report of the Intergovernmental Panel on Climate Change and one of the world’s leading climate experts.

Professor Thorne told the Climate Committee, which consists of the Taoiseach (Prime Minister), Tánaiste (deputy Prime Minister), Ministers of Public Expenditure and Reform, Social Protection, Agriculture, Climate Action, Tourism and Housing, that to keep the temperature below 1.5 Celsius above the pre-industrial era temperature, we need net emissions to reach zero by 2050. This requires halving methane emissions and getting carbon emissions to net zero.

You probably knew that. But then the devastating news was delivered that stabilisation of all effects of climate change is impossible in the next few centuries. Sea levels will rise by five metres.

There is nothing we can do to change this.

If you live in Cork City, Limerick, Galway, or Belfast you are in peril, especially if you are in junior infants’ class, typically a five-year-old. Here is what the sea level rise means for Dublin.

By the time our five-year-olds reach old age, Dublin will no longer contain Sandymount, Blackrock, Monkstown, Sandycove, Dun Laoghaire, and Ringsend on the south side and Malahide, Clontarf, Portmarnock and Sutton on the north side of the River Liffey. The Hill of Howth will be an island and there will be no Bull Island. The Liffey, by then hundreds of metres in width, will enter the sea at Phoenix Park. Dublin Bay will stretch from Cabra on the north side to Donnybrook to the south. The flooding will reach Lombard Street, near Trinity College.

Flood Map of Dublin 2100 (Image Climate Central)

The past 10,000 years have seen a remarkably stable global climate, allowing humans to develop from nomadic hunter-gatherers to settle in great urban centres facilitated by the industrial and agricultural revolutions. This climate stability is rapidly unraveling, according to Professor Thorne.

It will be worse elsewhere, such as on the Indian sub-continent, but we will feel the shocks, directly, economically, and in human terms, with mass migration to this country. We are at the edge of human livability in some areas already, such as the Horn of Africa, and this year, in parts of India.

If we are stupid enough to go to three Celsius above pre-industrial temperatures by the time our Junior Infants reach advanced old age, and this is where we are heading with current emission levels, 75% of all the planet’s biodiversity will be lost. Imagine what such a world would look like.

Many of our familiar plants and animals have ceased to exist. The photographs in The Irish Butterfly Book will likely show several extinct species. I wonder if the Wall Brown, Hedge Brown, Small Heath and Large Heath will still exist. These species are already in serious decline, and climate change and issues driving climate change are among the causes. The extinction list is also likely to contain the species that need well-drained skeletal soils: Dingy Skipper, Small Blue, and Pearl-bordered Fritillary.

The Pearl-bordered Fritillary breeds on violets growing on thin, fertile soils over free-draining carboniferous limestone in the Burren. These soils are vulnerable to water loss if hot, dry summers, as are the plants and dependent invertebrates. Photo J. Harding

There are studies concerning the link between the warming climate and butterfly declines. There are indications that a combination of climate change and pollution is damaging the habitat of the Wall Brown. Kurze et al. (2018) suggest that it is very likely that nitrogen enrichment from fertilisers is killing some species larvae on farmland while Habel et al. (2015) suggest that increased plant growth rates arising from nitrogen deposition, increased rainfall and climate warming are cooling the micro-climate at larval sites, driving declines of species that depend on nutrient-poor habitats.

Hazel bushes suffered dehydration during drought conditions on July 1, 2018. Photo J. Harding

A study that looked specifically at the Wall Brown’s decline, Impact of nitrogen deposition on larval habitats: the case of the Wall Brown butterfly Lasiommata megera by Klop et al. (2014) found that nitrogen addition to potted foodplants on which larvae were fed had beneficial effects on larval development. However, the study found the influence of nitrogen deposition on larval micro-site cooling the most likely reason for the decline: “The raised levels of green plant biomass under excessive nitrogen availability leads to an increase of both shading and green: dead ratios in the vegetation, which should be expected to result in a cooling of microclimatic conditions.”

Like Habel et al. (2015), Klop et al. (2014) believe the decline of heat-loving species “could be explained by a combination of excess nitrogen and climatic warming, with both factors enhancing plant growth in early spring and reducing the availability of warm microclimates.” Elevated temperatures at the larval micro-site, typically arising from a combination of unshaded bare patches of ground containing sparse foodplant vegetation and warm, dry, dead plant litter are critical to the caterpillar in spring when air temperatures are cool. If these findings are correct, geographical scale pollution reduction measures must be implemented along with measures to tackle climate change. If not, we could be lamenting the extinction of one of our formerly common and widespread butterflies.

However, in such a devastating context that Professor Thorne outlined, the fate of our butterflies may seem of small consequence, a trivial footnote to a doomsday of mass extinction and global crisis for mankind, with continued human existence at stake.

Thorne stated that a brief and closing window exists to secure a livable future if concerted global action takes place.

But the past decade has had the highest greenhouse gas emissions in human history.

Professor Thorne stated that technological solutions exist to produce low emissions, but investment, which is available, and leadership, are needed.

How, then, did the cabinet committee react to Thorne’s presentation? A few polite questions later, the ministers began to discuss sectoral contributions to emission reduction targets. The Irish Government reacted by producing, according to the Environmental Protection Agency (EPA) report published three weeks (May 31, 2022) after the briefing, an emissions policy that adds up to 28% of greenhouse gas (carbon dioxide, methane, and nitrous oxide)  reductions by 2030, not the required 50%.

When RTE’s HOT MESS programme sought an interview with any of the ministers who attended the briefing, no minister was made available.

Before we blame the Government, let’s look at ourselves. Do you want to sell your second car, get rid of your beloved SUV, pay higher taxes, and pay more for food?

I doubt it. But politicians need to lead public opinion, not follow it. Opportunities for leadership exist. Jim Hacker, the fictional minister in the British comedy, ‘Yes, Minister’, when asked to defy public opinion for the good of Britain, responded, “I am their leader. I must follow them.”

No more of that.

Policies that are unpopular now, will become more popular, over time, as people realise how crucial they are. Let us act so we don’t run out of it.

Limestone grassland in the Burren, June 29, 2018. The heterogeneity of these grasslands is threatened by the predicted hotter, drier summers predicted to be the norm by 2050. Photo J. Harding

Sources

Dublin Live (2022) Terrifying flood map shows what Dublin will look like by 2030 https://www.dublinlive.ie/news/dublin-news/terrifying-flood-map-shows-what-23608348 (Accessed 19 August 2022)

EPA (2021) EPA Greenhouse Gas emissions projections highlight the need for urgent implementation of climate plans and policies. Available at: https://www.epa.ie/news-releases/news-releases-2022/epa-greenhouse-gas-emissions-projections-highlight-the-need-for-urgent-implementation-of-climate-plans-and-policies-.php (Accessed 19 August 2022)

Habel, J., Segerer, A., Ulrich, W., Torchyk, O., Weisser, W., and Schmitt, T., (2015). Butterfly community shifts over two centuries. Conservation Biology, Volume 30, No. 4, 754–762, accessed 28 December 2020, https://conbio-onlinelibrary-wiley-com.jproxy.nuim.ie/doi/epdf/10.1111/ cobi.12656

Harding, J.,(2021) The Irish Butterfly Book, privately published, Maynooth.

Klop, E., Omon, B. & Wallis DeVries, M.F. (2015) Impact of nitrogen deposition on larval habitats: the case of the Wall Brown butterfly Lasiommata megera. Journal of Insect Conservation 19, 393–402. https://doi.org/10.1007/s10841-014-9748-z

Kurze, S., Heinken, T. & Fartmann, T. Nitrogen enrichment in host plants increases the mortality of common Lepidoptera species. Oecologia (2018) 188: 1227. https://doi.org/10.1007/s00442- 018-4266-4

Natural History Museum (2014) London’s Wild Times: Past and Present https://www.nhm.ac.uk/natureplus/blogs/whats new/tags/britain_one_million_years_of_the_human_story.html (Accessed 19 August 2022)

RTE (2022) Episode 12 Getting Hotter. Available at: https://www.rte.ie/radio/podcasts/22110709-ep-12-getting-hotter/ (Accessed 19 August 2022)

World Wildlife Fund (2021) The Return of the Wolf in Europe https://www.worldwildlife.org/stories/the-return-of-the-wolf-in-europe#:~:text=Wolves%2C%20along%20with%20other%20predators,effort%20to%20prevent%20livestock%20predation. (Accessed 19 August 2022)

 

 

 

 

 

 

Burren Outing Report 6th August 2022

A view from the summit of Mullaghmore, Burren National Park, County Clare.

Our Burren outing began at 10 am when we gathered at the unofficial car park at the crossroads in the Burren National Park. The sky was grey, streaked with pale, fearful blue but the air was still, with a hint of warmth. Perhaps we would be lucky.

Following introductions, we over-stepped a low Burren wall and entered the area north of the road, where limestone pavement, open grassland, and scrub are beautifully flower-rich, with the heavily sweet influence of Fragrant Orchid flavouring the breeze, imbuing the atmosphere with alluring exoticism. To be there at this time of the year is to step into a dream world. August may be seen as summer grown old, a little wrinkled from its long exertions, frayed and browning, the glowing bloom of earlier days thinning and paling, paradise lost. The grasses are tinged with oatmeal, the light lower, sharper, flowers bedraggled.

Burren Green moth is found only in the Burren, and nowhere else in Ireland or Britain.

The jaded look is challenged by the arrival of freshly hatched butterflies, especially our latest butterfly to take flight, the Brown Hairstreak, our main priority for this day. The Brown Hairstreak is the last Irish butterfly to emerge each year. Speckled Wood-sized, it is a most elusive species, common nowhere in Britain or Europe. Ireland has most of its brown Hairstreak populations in the Burren, with scattered presences in west Tipperary, south Galway, and in Mayo near Lough Corrib. But it is not easy to find, especially where tall oak trees occur, for the more active males tend to occupy tree-tops, rarely descending. The Burren has fewer tall trees, and very few oaks so we do see males at eye level, feeding on nectar, rather than aphid secretions on oak leaves.

The Brown Hairstreak is quite tame, especially in cool weather.

Females are especially richly coloured with warm orange-brown undersides, while males usually look paler. Males are more active, jinking around the canopy, especially in the mornings, seeking newly emerged females. Mated females and males spend the long afternoons feeding on bramble and tall hedge side Creeping Thistles.

A female Brown Hairstreak suns herself on a hazel leaf.

The overcast weather was against us, because the hairstreaks typically perch quietly on tall scrub, typically on hazel in the Burren. Before we reached likely habitat, we noticed the large population of fresh-looking Meadow Browns, sharply different from the diminished populations in the east, now in rapid decline, their life’s work already done. Common Blue, Small Copper, Ringlet, Grayling, and the occasional Small Heath were encountered in the tall sward.

Small Copper warming itself on limestone.

The scrub patch identified in previous years as a good source of Brown Hairstreak sightings was searched. Nothing at first but high up one was seen, restless around the canopy before settling, wings ajar, on hazel. We failed to coax it to land lower down, but at least we knew they remained faithful to their patch. “If it brightens up, and you’re still around, you should find more here.” I learned that this is what some of our group did in the afternoon when the sunny weather appeared. A female was also found later, and they are rather lovely, in their tame, quiet, approachable way.

The intricate patterning on the True Lover’s Knot is a delight to observe. This moth occasionally flies during the day.

Later we crossed the road, finding another traditional haunt and another, less camera-shy male, who did fly down to feed on Creeping Thistle. A male Vapourer Moth was seen and photographed close by, a nice addition to the Burren Green and True Lover’s Knot moths caught the night before and shown to our group.

The resting Common Blue blends well with the Wild Carrot blooms.

We later returned to our cars, for refreshments, and positive feedback on our outing. A great thank you to all who joined our outing, some having made long journeys to share an experience with nature. May the sights we saw live on in our memories, and may the amazing Burren continue to hold its amazing depth and range of wilderness and biodiversity.

A Burren Grayling resting on a rock. The species is abundant here during August.
Mountain Avens Dryas octopetala is a lovely arctic-alpine flower. It blooms again in late summer after flowering in May. This photo was taken on Mullaghmore, where this dwarf shrub is abundant.

Let’s Love Larvae

Some years ago, a gardener told me she was enjoying the butterflies in her garden. It was early in a sunny September, and a range of butterflies flapped their vibrant wings around the nectar-filled blooms in her compact, warm sun-trapping garden. Did she grow any plants to encourage the butterflies to breed?

No, came the emphatic answer. She hates caterpillars.

But you cannot have butterflies without caterpillars.

No, she still didn’t want them.

The clarion call to save biodiversity is a cry that meets with broad public support nationally and internationally. Yet for many people, conservation is something that happens somewhere else. It is not. It is everyone’s responsibility. Covering your garden with artificial grass, tarmac, concrete, and cobbles do little to save nature.

Mowing your garden every week is damaging to the prospects of most wildlife and yet it is an endemic practice in Ireland, the UK and much of Europe. Yet many of the same people, if asked, would claim to care about nature.

Just as you cannot have the butterfly without the caterpillar, there is no biodiversity without a loving and hospitable home for our wildlife.

For most people, including butterfly and moth lovers, the larvae are rarely seen. But in some cases, the larvae are extremely interesting and very beautiful. Here we show a selection of butterfly and moth caterpillars and tell you a little about them.

All photographs J.Harding except Alder moth F. Parnell.

A Cinnabar moth caterpillar on Common Ragwort. This is one example of a highly conspicuous caterpillar and is easily the most reported caterpillar. This larva feeds in groups when younger, and their brash colouring warns predators of their toxicity. The caterpillars absorb toxins from the foodplant which contains pyrrolizidine alkaloids which are fatal to livestock and humans if absorbed in sufficient quantity. This appears to make the larva distasteful too, and birds learn to avoid the caterpillar. Common Ragwort and Marsh Ragwort are native plants, important for pollinators, but the plant should never be allowed to grow in hay meadows where hay is used to feed livestock. The Cinnabar moth controls Common Ragwort, eating the flowers before seed can form.
Next is a green caterpillar, the larva of the Green Hairstreak butterfly. This one is feeding on Bilberry, a bog and heath plant. The larva is well hidden on its foodplants and is very hard to find in the wild. It pupates in summer and the adult emerges the following spring and summer. The larva is stated to be cannibalistic but it has been reared collectively in captivity without any fatalities.
Another green larva, the Cryptic Wood White, relies on camouflage to be undetected by birds. It lies flat against the stems of its foodplant, especially Meadow Vetchling, adding to its blending ability. This caterpillar is also remarkably hard to locate. Eggs are usually laid singly, meaning the larvae are well dispersed, presumably allowing the species to avoid predation. Larvae that blend with their food are typically edible.
Time for something exotic! This is the larva of the Common Swallowtail butterfly on Common Fennell growing against a limestone rubble wall in Gozo, Malta. The butterfly is rarely seen in Ireland but is a possible future colonist. The fleshy protuberance is an organ called the osmeterium, extended when the caterpillar experiences a threat. The organ emits a sour smell of rotting pineapple to deter predators. Strangely, this organ does not appear to be used by the larva in its final growth stage.
The Tussock moths produce wonderfully flamboyant larvae, and the Dark Tussock, a bog moth, is one example. It feeds on heather and sometimes gorse. Its dense covering of bristles must be unappetizing to Meadow Pipits, a bird frequent on bogs.
The Pale Tussock moth caterpillar is more widespread and even showier. This species breeds on birch, oak, apple, hazel, limes, elms, Common Blackthorn and Common Hawthorn. The larva is usually seen in late August and September when it appears on or near the ground when it leaves the tree to pupate among debris on the ground.
The Vapourer moth is another member of Lymantriidae, the tussock moths. In Victorian England, a Vapourer was the name for a braggart or boastful person, and this larva certainly boasts extravagant outline and livery. The larva feeds on willows, Bog-myrtle and the same trees used by the Pale Tussock.
We don’t have the iconic Purple Emperor butterfly in Ireland but we do have the Emperor Moth, a beautiful bogland, heathland, fen, mature dune, and scrubland inhabitant. The newborn larvae are black, resembling miniature Peacock larvae, but colour changes eventually culminate in the form you see here. This species uses a range of foodplants. In Ireland, it has been recorded on birches, Alder Buckthorn, willows, and heathers.
A clouded Yellow on Common Bird’s-foot-trefoil. The butterfly appears in Ireland every year but not in abundance, except in some special years, like 2000. It is very common in Southern Europe, emerging in early April in Tuscany and probably earlier further south.
The Narrow-bordered Bee Hawkmoth is a day flyer, and very popular among nature photographers. The caterpillar feeds on Devil’s-bit Scabious, and its apparently unnecessary purple markings make sense if you see the foodplant, which often contains dark purple blotches on the leaves and purple on the flowering stems. Like the other hawkmoth species, the caterpillar has a tail.
The Lackey moth belongs to the family Lasiocampidae, the Eggar moths. It breeds on a number of trees, especially Common Hawthorn, and is mainly southerly in its occurrence in Ireland. The larvae feed in large groups and bask on webs, which can be large and conspicuous. Like many moths with colourful larvae, the adults are rather cryptic. The adult Lackey is usually straw-coloured and nocturnal.
The Small Eggar is rare in Ireland, despite having common foodplants like Common Hawthorn. This photo was taken in the Burren, near Carran, on open limestone with scattered scrub. It overwinters as a pupa, sometimes for two or three winters before the adult moth emerges. The adult flies early in the year, from January to March.
This is the larva of the Narrow-bordered Five-spot Burnet moth, a black moth with red spots on the forewings’ upper surfaces. The larva feeds on Meadow Vetchling growing in a tall sward, often on damp soils. The moth, both in the larval and adult stage, is easily confused with a much commoner species, the Six-spot Burnet, which is abundant on dunes in summer.
The colourful larva of the Sweet Gale moth belies the subdued, grainy grey adult’s colouring. Oddly, this moth has two generations a year in Ireland but just one in Britain. It feeds on Sea Plantain, Ribwort Plantain, Sea Campion and woody plants like heather.
The caterpillar of one of Ireland’s rarest butterflies, the Pearl-bordered Fritillary, is feeding on Common Dog-violet in the Burren, County Clare. This larva leaps off its foodplant when it wants to bask, landing impressively on its feet. Like many larvae that develop in early spring, it spends long periods basking in the sun on dry vegetation while it digests its food. It also appears to use its basking site as a latrine.
The Knot-grass is another dull moth with a colourful larva. It has a range of foodplants, including Meadowsweet and Devil’s-bit Scabious. This one has coiled into a ring, a typical defensive pose for a disturbed larva.
Like the Pale Tussock larva, the handsome larva of the Alder moth is usually seen when it leaves the foodplant (Alder, birches willows, oaks) to pupate in rotten wood on the ground. Photo by Fionnuala Parnell.
The Dew moth is an orange-yellow black-speckled day and night flyer that can be seen in the Burren in May, June and July. The caterpillar feeds on lichens growing on rocks.
A Comma butterfly caterpillar on Common Nettle. The species include Hops, elms and willows in its diet. Since the larva was first recorded in Ireland on 17th May 2014 in Carlow, the Comma has been recorded breeding in several counties, including Wexford, Wicklow, Meath and Dublin. It has recently been recorded breeding in Irish gardens and appears poised to colonise the entire island.