The continuing story of Ireland’s biodiversity crisis

Recent reports by good investigative journalists give a comprehensive and accurate picture of the neglect and degradation of Ireland’s legally protected sites. One such 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.

View of the karst landscape at Gortnandarragh, County Galway.

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.

Flora-rich habitat at Gortnandarragh, but for how much longer?

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.

Heath vegetation, like this Bell Heather, is abundant in some areas, especially to the west of the road in the centre of the site.

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:

  1. (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.

Peat piled up on the bog.
This peat is placed where the limestone grades into the bog habitat at Gortnandarragh.

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.

Stone piled up on the site.
Stone piled up near the track that leads to the road that runs through the site.
A stone wall was made using limestone slabs with cleared stone and cleared woodland beyond the wall.

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.

 

 

 

Climate of Destruction

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.

Cool, wild and wonderful; Rowantree Hill Bog, Co. Fermanagh. J. Harding

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).

Portrane’s east-facing dunes as they were in 2007. The dunes in this photograph no longer exist, a victim of rising sea levels and massive coastal erosion. J. Harding
The edge of a dune at Portrane showing coastal erosion in February 2021. J. Lovatt
The local efforts to protect buildings at Portrane are shown in this image. Given the projected rise in sea levels, we can expect to see many more of these attempts. J. Lovatt

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)

The Wall Brown is in steep decline in Ireland, Britain and in Europe. This endangered butterfly is believed to be suffering the effects of agricultural and climate change. J. Harding

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).

Sphagnum moss, the bog builder, and sundew, a peatland specialist plant that consumes insects. J. Harding

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?

Unlawful damage of a Bord na Móna bog that is supposed to be restored under the Government’s scheme to tackle climate change. J. Harding
The peat cut from the Bord na Móna bog laid out to dry. The peat remains on the site weeks after the activity was notified to Bord na Móna and the National Parks and Wildlife Service, the administrators of the bog restoration scheme. J. Harding

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.

Mass destruction of our bogs continues apace. This is not cutting for domestic use but for commercial gain.  See also the photograph below. J. Harding

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”.

Coastal habitats along the east coast may soon disappear under water. J. Harding

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.

 

 

 

 

 

 

Letting the life back in

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.

Notice of BCI fundraiser
Spreading the native gospel: native wildflowers for sale.
Butterfly photos taken by Sam, aged 7, a budding naturalist and expert photographer. From top left: Silver-washed Fritillary, Peacock, Small Tortoiseshell, Red Admiral.
Thank you to All!

 

 

Why is my Buddleia Empty?

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!

Peacock butterflies will be found in gardens especially from mid-August to early September. J. Harding
Holly Blue, male, basking on ivy. Look out for it now. J. Harding
Small Copper, female. This species is in my garden now. Photo J. Harding
Small Tortoiseshells can fly well into November. It occurs in the largest numbers, typically, during September. Photo J.Harding
The Comma butterfly. Look for now but especially later in September and well into October-check flowering ivy and over-ripe fruit. Photo J.Harding
Painted Lady butterflies will be found in flower-rich gardens in late summer, especially near the south coast, J. Harding
Red Admirals will usually visit in September and into October. Check flowering ivy and over-ripe fruit. J.Harding

 

 

 

 

Mighty Whites

The recent hot, sunny, dry spell (a very hot spell in an Irish context) with easterly breezes has coincided with the appearance of an abundance of Large Whites and Small Whites, probably a mixture of native-born and immigrant butterflies. We are also experiencing a good-sized emergence of Green-veined White butterflies and all three species can be found flying together. Where it occurs, the Brimstone mixes with the other white species, making for much confusion.

How do we separate these white butterflies?

The Green-veined White is a widespread species and is not known as a migrant. It is especially common in damp and wet grassland and along damp hedges and streams. It is similar in size to the Small White (wingspan is c. 40-52 mm in the Green-veined White, c.38-57mm in the Small White, according to Newland et al. (2015)), and will often occur with this species in gardens, where the Small White and Large White breed on Nasturtium and brassicas. When seen in flight these two are very hard to separate.

The male of both species has one spot on the upper side of the forewing, while the female of both species has two spots on the upper side of the forewing. However, when settled, the Green-veined White shows a dusting of dark scales along the veins on the upper sides and undersides of the wings. A more subtle change is the ground colour of the upper sides of the wings. The Small White has a milkier appearance while the Green-veined white is a clearer, brighter white, especially in the male.

Green-veined Whites: male on the left, female on the right. J. Harding
Green-veined White showing distinct ‘vein’ markings on the hindwing underside. This is the only Irish white with these markings. J. Harding
Small White, female on Sow Thistle. Note the milkier white on the wings. J. Harding
Small White, male; note it has one forewing spot, unlike two in the female. J. Harding

The Large White is appreciably larger than the Small and Green-veined Whites (Newland et al. (2015) give a wingspan of 58mm in the male and 63 mm in the female but much larger specimens are very common; a female I measured recently had a wingspan of 72mm) but smaller specimens of the Large White also occur. In addition, a butterfly in flight seen on its own will present identification difficulties. When settled, identification is simple especially when the wings are held open. The Large White, in both sexes, has a much more extensive black wing-tip that extends much further along the outer and inner edges of the forewing than in the Small White.

Large White, female. Note that she has two forewing spots on her upper sides, like the female Small White and Green-veined White but the Large White shows far more pronounced wing-tips than the latter two species. J. Harding
The male Large White has no forewing spots on its upper sides but it does have two forewing spots on the forewing underside. Its upper sides are clear white with a forewing tip that is more extensive than in its smaller white relatives.

There may be confusion between Large and Small White males when these are settled with closed wings. Here are photos of both.

Small White male showing one black spot on the forewing underside. There is another black spot just below the visible spot, but this is hidden behind the hindwing. J. Harding
Here is a Large White showing the prominent forewing spot on the underside of the forewing. There is another black spot just below the visible spot, but this is hidden behind the hindwing. J. Harding

The separation features in the settled Large and Small White, apart from the size of these butterflies, lies in the larger size and squarer appearance of the spot in the Large White.  A further separation feature is that the yellow costa (outer margin) on the hindwing extends further along the costa in the Large White.

Another white flying now, the Brimstone, can be confused with the Large White, being similar in size and overall colour, especially when seen in flight in sunny conditions. However, it is only the female Brimstone that can be confused with the Large White because the male Brimstone, true to its name, is sulphur-yellow but the female is a pale greenish-white.

Unlike the Large White, the Brimstone almost always settles with closed wings. Furthermore, she has no black markings on her wings and has a pointed apex on the forewing. She also has dull red markings on the thorax and the base of the hindwing and dull red antennae. The Brimstone is much rarer than the other whites but all whites can be found in areas occupied by the Brimstone.

Female Brimstone. Note the brown spot on the forewing and hindwing, the hook on the forewing and hindwing, and the more prominent leaf vein markings. J. Harding

The male Brimstone, being yellow, is not a confusion risk, but we cannot resist showing you a photo of this handsome butterfly.

Male Brimstone showing bright yellow wings. J. Harding