Month: June 2022

Butterfly Conservation UK has recently produced a new Red List for Britain’s butterflies, and the news is not very good.

The declines reported by the Red List authors are linked mainly to habitat loss, not climate change. But climate change is playing a negative role in the fortunes of more northerly species.

Head of Science for Butterfly Conservation, Dr Richard Fox, says: “Shockingly, half of Britain’s remaining butterfly species are listed as threatened or Near Threatened on the new Red List. Even prior to this new assessment, British butterflies were among the most threatened in Europe, and now the number of threatened species in Britain has increased by five, an increase of more than one-quarter. While some species have become less threatened, and a few have even dropped off the Red List, the overall increase clearly demonstrates that the deterioration of the status of British butterflies continues apace.”

While land-use change remains the most important driver of decline, the impact of climate change on butterflies is also evident in the new Red List, with all four British butterflies with northerly distributions, adapted to cooler or damper climates, now listed as threatened (Large Heath, Scotch Argus, Northern Brown Argus) or Near Threatened (Mountain Ringlet).

Britain currently has 59 species (the Red List assessed 62 species, 4 of which are assessed as extinct, although one of these, the Large Tortoiseshell, has been recorded breeding this development occurred after the assessment for the Red List). The List covers Britain only, not the UK as a whole. Disturbingly and perhaps presciently for Ireland’s butterflies, some of the species we have become more concerned about have been uplisted on the Revised Red List of British Butterflies.

The Large Heath ranked vulnerable on the Irish Red List (2010) has been up-listed from Vulnerable to Endangered on the British list. The Grayling ranked Near Threatened in Ireland, has been up-listed from Vulnerable to Endangered on the British list. The Small Heath ranked Near Threatened here, has moved from Near Threatened to Threatened on the British list.

The most disturbing assessment concerns the Meadow Brown, assessed as Least Concern. However, this finding is, to my mind, dubious. The species has shown a major increase in the rate of decline over the period of the assessment (2010-2019) but is assessed as Least Concern because of the potential for a rescue effect, with the British population having the potential to receive influxes from Ireland and Europe.

This assessment makes little sense if the decline is attributed to land-use changes. The habitat does not become suitable for the species simply by receiving immigrant Meadow Browns. A mathematical model shows a projected decrease of 28% (2013-2022). The assessment must apply the International Union for the Conservation of Nature (IUCN) process for assessing the status of species, but this should set alarm bells ringing shrilly.

The decline of such a widespread, undemanding habitat generalist suggests widescale environmental degradation. The Victorian Lepidopterist C G Barrett wrote that there is “hardly a grassy field in the United Kingdom from which it is wholly absent.” This is not the case today, for Britain or Ireland.

In better news, conservation measures have helped to improve conditions for the Pearl-bordered Fritillary in Britain which has moved from Endangered to Vulnerable. However, these conservation measures must be ongoing, because this butterfly requires a determined programme of scrub control and rough grazing for its survival in many regions. In Ireland the 2010 Red List ranked this species as Endangered, applying the precautionary principle because the butterfly has such a restricted distribution here, occurring only in the Burren and close to the Burren.

The Wood White, ranked Near Threatened here, remains Endangered in Britain. This species occurs mainly in the Burren and in other areas containing exposed Carboniferous limestone, in scattered locations from just south of Ennis to southern areas of County Mayo.

How are butterflies dealing with land-use changes and climate change on the continent? Broadly, in northern Europe butterflies are in trouble while in southern Europe populations are more stable. Woodland species are doing considerably better than grassland species.

The European Grassland Butterfly Indicator is based on the national Butterfly Monitoring Schemes (BMS) in 19 countries across Europe, most of them in the European Union. The indicator shows that from 1990 to 2011 butterfly populations have declined by almost 50 %, indicating a dramatic loss of grassland biodiversity. This also means the situation has not improved since the first version of the indicator was published in 2005. Of the 17 species that the Indicator assessed, eight have declined in Europe, two have remained stable and 1 increased. For six species the trend is uncertain.

The eight species that showed declines were (species that occur in Ireland in bold) Small Heath, Wall Brown, Small Copper, Dusky Large Blue, Meadow Brown, Common Blue, Marsh Fritillary, and Large Skipper.

From Seville and Cordoba comes the startling news that Common Swift Apus apus and Pallid Swift Apus pallidus nestlings are being killed by extreme heat or when attempting to escape the extreme heat. Hundreds of nestings are being found on pavements, near death. Great tit chicks in Montpellier are starving to death because their parents cannot forage in 45-degree heat.

These are cavity-nesting birds, which often breed in cultural environments such as cities, parks and gardens, making the effects of extreme heat easily observable.

We might be missing what is going on elsewhere and to less conspicuous wildlife, like our moth species.

Apart from drastic global action needed to reduce emissions of greenhouse gases, we need to protect landscapes, like the Burren, to buffer the effects of a warming climate. Bog restoration, grassland restoration, native woodland restoration would also help.

One step you can take right now to express your support for our wetland habitats is to sign the petition in support of the establishment of the National Peatlands Park in Northwest Kildare and East Offaly. The petition is being run by No Planet B, a dedicated group of young environmentalists, ably led by Butterfly Conservation Ireland member Niamh Cowdell. The petition is here: https://chng.it/hYm7vfJjJT

 

Lullybeg Nature Reserve is a Bord na Móna rehabilitated cutaway area, managed since 2010 by Butterfly Conservation Ireland. It is listed in the Bord na Móna Biodiversity Action Plan 2016-2021. This is an important conservation location (rated Nationally Important in the Kildare County Development Plan) as it is home to a population of Marsh Fritillary Euphydryas aurinia, the only protected species of butterfly (and the only protected invertebrate) in Ireland (protected under Annex II of the Habitats’ Directive 1992). Other important butterflies present are Dark Green Fritillary Speyeria aglaja (ranked Vulnerable), Wall Brown (ranked Endangered), and Small Heath Coenonympha pamphilus (ranked Near Threatened). Twenty-six butterfly species have been recorded on the reserve. The rewards of conservation management and scrub removal/control are evident as the already impressive list of flora and fauna recorded on site is increasing. The site is used as a transect for the Irish Butterfly Monitoring Scheme (IBMS) run by the National Biodiversity Data Centre, with 12 years of IBMS records underlining the site’s importance for Lepidoptera. Moths that are present on the site include species ranked Near Threatened on the macro-moth Red List published by the National Parks and Wildlife Service in 2016 (Allen et al. 2016), such as Small Chocolate-tip Clostera pigra, Dark Tussock Dicallomera fascelina, Small Purple-barred Phytometra viridaria, and species ranked as Vulnerable, such as Narrow-bordered Five-spot Burnet Zygaena lonicerae. Teal (Amber-listed), Woodcock (Red-listed), Snipe are among the breeding birds present. Merlin (Amber-listed), Buzzard, Kestrel (Red-listed), Sparrowhawk, Jay, Raven and Linnet (Amber-listed) occur here.

One of the pleasures of being in an area of high biodiversity is encountering the sheer range and abundance of invertebrates. Yesterday, for example, there were hundreds of young grasshoppers, their abundance a reassurance of the health of the habitats at Lullybeg. Recording what is observed using a camera is a great way to build memories of what is present, and a great way to record species one is unsure of for identification later, using reference texts on online resources. The quest for that perfect photograph, capturing a wild animal at its best, is another motivation for many nature lovers.

Here are some images from the reserve taken this week. Enjoy!

All images copyright J. Harding

 

The bramble is in bloom on Ireland’s highways, Cross-leaved Heath is flowering on our wet heaths and bogs, buttercups are starring in old pastures and our limestone areas are awash with trefoil, vetches, cranesbills, and Burnet Rose. There is a gap in June vacated by the spring butterflies being on their last wings while summer species have not entered the fray, so June can be eerily quiet in our countryside. The Meadow Brown is just beginning to bob jerkily around the grasses and flowering bramble, while the Ringlet is not out yet. We are awaiting our first Dark Green Fritillaries and while the Small Tortoiseshells are hatching, they are mainly beyond the public eye, staying close to their breeding plants in the fields and staying away from our gardens and flowery grasslands.

There are some serious delights to be savoured, however, and here we feature some.

The first may seem an odd choice. Mainly a spring species, the Orange-tip can be found flying throughout June, especially on more exposed sites where it may emerge later. One of our loveliest species, there are plenty of larvae to be found on Cuckoo Flower seed pods, on plants in sunny positions.

The male Green Hairstreak is a tiny, hyperactive pugilistic character but the female is less bullish and far likelier to sit quietly in warm sunshine, especially when not egg-laying. The species always perches with closed wings, and one’s first sighting is unforgettable. This one was careful not to land within the field of vision of a crab spider perched on a buttercup; crab spiders are voracious butterfly killers but their peripheral vision is so poor that a butterfly can land adjacent to it without being noticed but passing across its field of vision is lethal. A swift paralyzing bite is delivered to the butterfly’s thorax, and the venom then dissolves its innards. The Green Hairstreak in this photo moved from the buttercup to an adjoining white clover, avoiding the spider. The Green Hairstreak should be sought on bogs and wet heaths, especially near scrub.

A butterfly in flight on our wilder grasslands during June is the Marsh Fritillary. Typically a low flier, males dart wildly across their patch in sunshine but quickly settle when cloud covers the sun. Our only protected butterfly needs help, because our flower-rich grasslands are in poor condition and according to data in a 2019 report by Ireland to the EU, some of these habitats are not doing well. For example, the future prospects for orchid-rich grassland are: Range: poor, Area: bad and Structure and functions: poor. The overall assessment of the conservation status for this habitat is deteriorating. But on Butterfly Conservation Ireland’s reserve at Lullybeg, the species is happily booming in 2022. Over 100 were spotted on one day in late May. Here is a male on Ragged Robin.

Finally, a humble member of the brown family, the Small Heath. Again, this one needs watching because land-use changes generally destroy its preferred habitat, grassland on infertile, unpolluted soils. This is one of those butterflies that we used to take for granted. Not any more.

If you see any of these butterflies, why not let us know? Our Records page shows you how to send your records: see https://butterflyconservation.ie/wp/records/

Happy hunting!

 

Preparation for the moth morning on Saturday June 4th began months ago, when we did some preliminary trapping on Eddie and Denise Smyth’s farm which lies just south of the Grand Canal near Umeras Bridge, in County Kildare.

Results showed what we expected; an abundance and range of moths in rich habitats. The farm contains scrub, species-rich wet grassland, tree lines, and a garden with flower beds and borders.

The traps were set on Friday, and we noted the sky was clear, not a great sign for moth activity unless it is very warm. The morning was cool with a breeze that was not strong but certainly with a bite.

On the plus side, the traps were set in sheltered spots so we had our hopes. Our moth enthusiasts were led by Philip Strickland, BCI’s moth specialist. We carefully inspected the area around the trap for moths that settled close by, a habit of some species attracted by light but only occasionally enter traps.

While abundance was suppressed by the weather conditions, the moths of the area were well represented, with real beauties making an appearance, such as Cinnabar moth, Buff-tip, Elephant and Poplar Hawkmoths, White and Buff Ermines, and less showy stalwarts including Small Square-spot, Clouded Bordered Brindle, Clouded Brindle and Brown Rustic. Plenty of micro-moths were tucked into the egg cartons that line the interior of the traps, much there to interest Philip, who has found a number of species previously unknown in Ireland.

Pale-shouldered Brocade was especially numerous, probably because of the abundance of willow, and Green Carpet and Seraphim were also in evidence. A species that excited admiration was the Eyed Hawkmoth, a large and dramatic species whose polychromatic hindwing uppersides deliver a striking foil to the cryptic bark-blending forewing uppersides.

Our group was then treated to the warmth of Eddie and Denise Smyth’s hospitality, when we were seated indoors for our post-moth tea and snacks. Conversations about our nation’s biodiversity flowed, and hopefully new contacts and ideas were generated. I enjoyed the event enormously, as did everyone else.

Butterfly Conservation Ireland thanks all who took part, especially Denise and Eddie for hosting our event.

Photos J. Harding