Decline of Irish insects reflects inconsistent approach to protecting endangered species

The approach taken to protect endangered species is riddled with inconsistencies. Some species get a lot of attention and others, for no obvious reason, get none.
In Ireland birds such as the curlew and corncrake (deservedly) get multimillion euro projects to boost their populations, while nightjars and ring ouzel (also critically endangered) get nothing. The basking shark recently became the first marine species to get legal protection, though it is only one of a number of shark species that are endangered. Atlantic salmon enjoys frequent media articles while Arctic charr and twaite shad, also threatened fish, never enjoy the limelight. But the divide becomes even more stark when it comes to animals that are not reasonably large or in possession of a backbone.
According to the UK’s Royal Entomological Society, 90 per cent of all species on the planet are insects yet in Ireland only one insect enjoys any kind of legal status: the marsh fritillary butterfly, which is listed under the EU’s habitats directive. Even this protection is limited, requiring only that some areas be designated for them as “special areas of conservation”.
This is not because insects are under less threat than other species groups, or because they are less important. Insects are arguably the workhorses of terrestrial ecosystems, breaking down waste and recycling nutrients, pollinating flowering plants and providing food for fish, amphibians, birds, mammals (especially bats) as well as other invertebrates.
Diminishing numbers have been highlighted through the apparent lack of dead insect splatter on car windshields, something that was empirically demonstrated in a study from Denmark published in 2019 and which noted a 80-97 per cent reduction in insect abundance over 22 years.
Although insects are never very large, they are frequently charismatic. Even in Ireland we have spectacular butterflies and moths, impressive beetles with iridescent carapaces and, of course, bees, up to 100 species of them, which have managed to connect with the wider public due to their industrious nature.
The all-Ireland pollinator plan, launched in 2015 by the National Biodiversity Data Centre, is a rare example of a conservation programme aimed at insects, albeit encompassing a range of species, not only bees but hoverflies, wasps, moths and butterflies that are appreciated for their pollination services. This programme has uniquely managed to engage communities across the country with science-based conservation measures to address the extinction crisis. However, despite this, the evidence suggests that bumblebee numbers “remain in a precarious position”, while one species that is part of their monitoring programme, the large carder bee, continues a “serious decline nationally”. Data for butterflies shows no species has increased in number since monitoring began in 2008.
While pollinators have captured the public imagination, the many groups of insects that do not pollinate flowers (ants, aquatic flies, many varieties of beetle, dragonflies, grasshoppers and weevils, for instance) remain overlooked.
It is widely cited that one third of Ireland’s wild, native bee species are threatened with extinction, but this pattern is mirrored across the insect groups that have been studied. Among them are seven species of moth that are classified as “critically endangered”, including the yellow-ringed carpet which is found in only two locations in Co Antrim.
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Nearly a third of mayflies are threatened with extinction, including the scarce summer mayfly, most recently recorded in the 1990s from only one area in Co Galway. The hairy wood ant, a species conspicuous in the forests of Scotland and Scandinavia because of its enormous nests constructed from pine needles, plays an important role in woodland ecology but is in “serious decline” nationally and was last recorded in only five localities in three counties.
Aidan O’Hanlon is entomology curator at the National Museum of Ireland. He says there are about 12,000 documented species of insect in Ireland, but it is estimated that the real figure is nearer 16,000. This is a large number but is dwarfed by the one million insects that have been named worldwide (which itself is just a fraction of the true diversity). “They’re the most diverse group of animals in the world and also in Ireland, comprising half of all our fauna,” he says. Being small and with many species quite similar to one another means identification of groups, such as parasitic wasps, is a specialist business.
Nevertheless, O’Hanlon believes insects are well-studied in Ireland compared with many places. He knows from the museum collections, which go back to the 1800s, that species that were once common are now scarce. “We have records for some solitary wasps from north Dublin and Wicklow and I try to go out and find them, but they’re just nowhere to be found. It’s definitely not for lack of effort or looking in the right place … and that’s an experience I share with a lot of entomologists in Ireland.”
Globally, less than 1 per cent of the known insect species have had their conservation status assessed, but in Ireland O’Hanlon points out “red lists” have already categorised the threat level of about 1,000 Irish species, including butterflies and moths, mayflies and stoneflies, water beetles and dragonflies. Developing individualised conservation plans for all of these species is not practical and he believes that “the best thing to do is to preserve and enhance the habitat where these animals live”.
One example of a project where an insect takes centre stage (the only example I could find, in fact) is that of the great yellow bumblebee on the Mullet Peninsula/Erris region of Co Mayo. Where once it was widespread in Ireland, by 2014 this area was the last holdout in Ireland for this charismatic bee.
Looking a bit like a flying piece of Christmas tinsel, the great yellow bumblebee was never common but is now endangered with extinction. It was the Belmullet Tidy Towns group that recognised the importance of the bee and encouraged students to carry out research on it. In 2021-2022 this formed the basis of an environmental innovation partnership (EIP), funded by the Department of Agriculture. Margaret Tallott of the Tidy Towns group told me “the response was great. Once we had the EIP it allowed us to build relationships with local farmers and that is essential”.
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The EIP provided payments for farmers for delayed mowing and grazing as well as creating linear features for pollinators. “Farmers have to be paid for this,” Tallott said. While walking around Belmullet, the visitor will notice the array of pollinator-friendly green spaces and striking murals of the local wildlife, including the great yellow bumblebee. Local schools are on board and there is even a beautifully illustrated short story following the plight of Bláithín the bee and her search for flowers.
Farmers who were involved in the EIP are now a part of the EU-funded Life on Machair project, which provides enhanced payments for good quality habitat. The project’s ecologist, Karina Dingerkus, showed me around one of the machair habitats on the Mullet Peninsula (a rare type of sandy grassland), which is known to have great yellow bumblebees. She told me how the research that has been carried out shows this species is fussy and prefers particular plants that are found in abundance on machair, such as kidney vetch, knapweed, ragwort and red clover. But the measures will benefit all pollinators, indeed all kinds of insects and this region is also home to the red-banded sand wasp and Manchester treble-bar moth, which are also endangered.
The EIP worked, in so far that it was proved farms in the scheme had more great yellow bumblebees, but this has not been enough to stop its general decline. While in 2022 there were 78 records of the bee, in 2023 there were only 29. This year has not been agood, probably due to the cool temperatures, and during our search of the machair we did not encounterany. The fact remains that without measures to improve the habitat in the wider landscape, not just in small and dispersed pockets, the future for insects, like so much of our wildlife, remains precarious.