Latest news with #insectdecline
Yahoo
21-06-2025
- Science
- Yahoo
Australia's sky could change forever after winter ends
When Aussies look up into the sky at the end of winter, there will be a noticeable difference from what we saw a decade ago. Bogong moths used to migrate across Victoria, NSW, Queensland and South Australia in their billions, reportedly blocking out the moon, but in 2017 and 2018 their numbers crashed by 99.5 per cent. Mortein once advertised its sprays could be used to kill bogong moths, but that advice was eventually removed after the species was listed as endangered in 2021. While the moths have been in steady decline since the 1980s, it was the sudden drop in numbers during the Millennium Drought that caused the average punter to take notice. The situation has a leading conservation biologist 'extremely worried' both about the moth and the animals that depend on it as a food source, like the critically endangered mountain pygmy possum. Dr Marissa Parrott from Zoos Victoria said it's accurate to say 'within a generation, Australia has changed' as invertebrates vanish from the landscape. 'In Australia, with animals like the bogong moth, it becomes apparent things can go wrong very quickly,' she told Yahoo News. For thousands of years, bongog moths have meant spring was here, and Christmas beetles were a sign of summer. These insects are wound up in memories from our childhoods, but today both are seldom seen. '[Insect] numbers are all declining across time. But then you get those big events like a major drought, flood or bushfires and they can wipe out entire species,' Dr Parrott said. 'We're seeing that every day, that these animals are struggling, and we've probably lost far more invertebrates than we could ever even imagine… and it's only getting worse. We really need to change.' Parrott notes the problem is a global one, with many referring to it as an 'intertebrate apocalypse'. Often, people don't realise the insects are gone until their crops stop being pollinated or the birds that eat insects suddenly vanish. When it comes to bogong moths, the good news is that since 2018, there has been a trend towards recovery. But the species' future is far from secure. Zoos Victoria's Moth Tracker project, an online platform where people around the country can report bogong moth sightings, was launched in 2019, and last year was its best season on record. Between September and December, there were 1,956 sightings, and 1,089 were verified by the expert team. Some swarms (groups of over 100 moths) were even observed in 2024, something that hadn't been seen in years. "It was wonderful to see that again, but they're only one more drought from those numbers dropping right back low again. We need to have a long-term plan to protect and recover them," Parrott said. Related: 🚨 Call to protect Australia's changing insect landscape A bogong moth will live for around a year, with each dying after the autumn breeding season. The caterpillars live underground throughout the winter and then migrate up to 1,000km across Australia to alpine regions in the warmer months. Those that survive the feeding frenzy from native animals fly back across the country to their breeding ground to lay their own eggs. 'Each female can lay up to 2,000 eggs, so their numbers could bounce back quite quickly if we can protect them,' Parrott said. 🌏 'Shocking' jellyfish find could change the way Aussies visit the beach 🔍 Rare find inside ancient cave after tourists banned for years 🏡 Key detail caught on front yard security footage sparks alarm Earlier this week, a new study published in the journal Nature revealed bogong moths used constellations of stars and the Milky Way to navigate their migration routes. This upended a belief that moths simply flew towards the brightest light in the sky. The team from Lund University, the Australian National University (ANU), and the University of South Australia compared their abilities to those of migratory birds. Insects like bogong moths face multiple threats, including pesticides for agriculture, deforestation, climate change and light pollution. A 2017 study of select conservation areas in Germany found the insect biomass had dropped by 75 per cent in 27 years. Love Australia's weird and wonderful environment? 🐊🦘😳 Get our new newsletter showcasing the week's best stories.
The Guardian
17-06-2025
- General
- The Guardian
Swifts' decline: how can Britons help these remarkable birds?
The swift (Apus apus) is an acrobatic aerial bird, a remarkable sprinter and endurance flyer that rarely touches the ground. When these sickle-winged birds do come down – after several years in perpetual flight, even sleeping midair – it is to nest in the eaves of roofs across Europe after spending winters in sub-Saharan Africa, migrating 7,000 miles (11,000km) every year. They are celebrated by nature-lovers, artists and poets as they race through city skies on long summer evenings, filling the air with their screaming calls. The fastest bird in level flight (top speed: 69mph/111kph), they feed on airborne insects. Swifts are in trouble because of steep declines in insects, but also because they are losing traditional nesting sites. Swifts once nested in caves and hollow trees but moved into buildings hundreds of years ago. Modern insulation, particularly in roofs, removes the crevices and cavities where they have nested for centuries. Grim. Swift populations slumped by 66% between 1995 and 2022 in Britain and have continued a rapid downward trend. Since the last count of 59,000 breeding pairs, the population this summer is set to be just 40,000 pairs. In five years' time, there could be fewer than 25,000, unless action is taken. Declines are not so pronounced across continental Europe despite similar insect declines. Countries such as Germany and France appear to have retained more nesting sites in old buildings than in Britain, where few buildings constructed after 1944 can accommodate swifts. A swift brick is a hollow brick which slots into the brickwork of new or old homes, providing a cavity where swifts can nest. The bricks have also been found to help other cavity-nesting birds, including the rapidly declining red-listed house martin, house sparrow and starling. Other species including blue tits, great tits, nuthatches and wrens will also nest in the bricks. Swift bricks are made by brick manufacturers large and small, and typically cost about £35. There is a British Standard for them and some developers are already fitting them to new homes. Three years ago, the writer and bird lover Hannah Bourne-Taylor launched a campaign to oblige every new home to be fitted with a swift brick. When in opposition, the UK Labour party supported the 'swift brick amendment', first tabled by the Conservative peer Zac Goldsmith, to do this in England. Now in government, Labour is resisting attempts by its own backbench MP Barry Gardiner to insert a swift brick amendment into the controversial planning and infrastructure bill. Labour is reluctant to impose additional regulations on housebuilders as it attempts to address the UK's housing affordability crisis with a big push for new homes. Nearly 30 housebuilders have voluntarily agreed to install one brick for every new home built. Labour's latest move is to suggest adding swift bricks to national planning policy guidance so that all England's local planning authorities insist on them for new homes. But Bourne-Taylor says this won't guarantee more swift bricks, because many planning authorities lack the resources to ensure planning conditions are met. A recent study found developers, who make multi-billions in profits, were not providing 75% of the nesting boxes stipulated in planning permissions. 'By refusing to mandate swift bricks, the government is making it clear to their voters that they do not care about nature because this would be the easiest nature recovery action, ever,' said Bourne-Taylor. 'Loads of people have told me that they will never vote Labour again because of how the government have acted on swift bricks.' Wooden swift boxes are widely available and are suitable for swifts, provided they can be installed at least 4.5m above ground and not on a south-facing aspect, because this is too hot for the nesting birds. Retrofitting an integral brick is more expensive but slightly better because it provides a cooler space and will last longer than a wooden box. Even if a swift box is ignored by swifts, it will be a boon to other birds. And there are many other ways to help swifts. The Swift Local Network unites swift lovers across Britain. Local groups rescue fallen birds and protect existing nesting sites: talking to neighbours who have swifts in their roofs raises awareness if roofs are renovated. The government's commitment to insulate Britain will be welcomed by all environmentally minded voters, but this makes it more crucial than ever that swift bricks are integrated into all new homes. Campaigners are emailing the housing secretary, Angela Rayner, to let her know. Site-faithful swifts sometimes take a while to discover new nesting opportunities. If house sparrows first take up residence, this is good news because swifts often seek out nesting spaces where they see sparrows – they are a signal for swifts that there are good homes here! Some people play swift calls from a window close to a new nestbox to attract curious swifts when they first arrive back in Britain in May. This can help, but usually only in areas that already have swift populations.
The Guardian
17-06-2025
- Science
- The Guardian
Insects are dying: here are 25 easy and effective ways you can help protect them
Insects are in trouble. Around the world, scientists are reporting catastrophic declines in their numbers, even in nature reserves that are largely protected from human touch. We are also beginning to see huge drops in the populations of other animals – such as birds – that depend on insects as food. Many of the drivers of those declines are structural, and require strong action by governments to turn around. But there are clear, easy steps that anyone can take to support the insect world. For species under such pressure, any respite is important, and we can create refuges for insects in a world increasingly hostile to their survival. In creating better habitats for insects, you can also reap the benefits: thriving gardens, more songbirds, and a healthier web of life. Here are 25 small, achievable, science-backed actions you can take today – at home, in the garden, or out in the city. Everyone has seen moths circle a bulb at night. But if that light stays on, researchers estimate one-third of insects trapped in its orbit will die before morning. Light pollution is a huge driver of insect declines: it changes insect behaviour and can even make leaves too tough for them to eat. It is also a relatively easy one to solve, says Brett Seymoure, a behavioural ecologist at Washington University in St Louis. 'Once you turn off a light, it is gone. You don't have to go and clean up, like you do with most pollutants. I am not saying we need to get rid of light at night, I think we just need to use it wisely.' You can help by switching off your outdoor lights or putting them on a sensor, and shading windows so they're not shining out into the night. You can also ask your local council to consider switching off some street lights for at least part of the night, particularly in parks and nature reserves – a move that studies have shown benefits insects and saves councils money. One of the best things you can do for insects is cultivate native plants, says Prof Douglas Tallamy, an entomologist at the University of Delaware. Local insects have evolved alongside local plants, and adapted to specific bloom shapes or leaf textures – many bees, for example, will only visit a single type of flower, even if others are growing nearby. Imported ornamental species and foreign plants often don't work as food or shelter for local species – by installing native plants, you can help insects get the food they need. Clothing moths are a huge pest in many households, chewing through winter coats, jumpers and wool carpets. But insecticides such as moth bombs can kill off every other insect in the vicinity. Now, some experts – including museums, which can't expose their artworks to chemicals – are experimenting with a natural ally: tiny parasitic wasps. The wasps are minuscule, barely visible to the naked eye, and lay eggs in moth larvae. Once the moths are gone, the wasps go too. The tiny wardrobe allies have been trialled by the National Trust, and used for pest control on cassava crops. You can order sachets of the wasps online. Even on the coldest winter days, compost heaps provide warm, safe habitat for insects to thrive. Over time, compost also improves soil structure and fertility, providing food and habitat for other garden insects. If you don't have a compost heap of your own, many organisations run neighbourhood composting schemes. As the climate heats, droughts are ramping up – and insects are struggling to survive the dry conditions. Providing sources of water with a basin, puddle, pond or bowl can help. Keep in mind that bees can't swim, so deeper water sources will need either a clear rim to drink from, or 'islands': according to University of California, floating corks or piles of rocks can work. Research has also shown that bees get important nutrients from 'dirty' water, where leaves or algae are breaking down, so don't keep your bee pools pristine. When trees shed their greenery, resist the urge to rake them up: leaf litter is a crucial habitat. Researchers have found that raking up leaves reduces moth and butterfly numbers by 45%, beetles 24%, and spiders up to 67%. Save yourself the trouble, and let the leaves lie. Creating food for insects can happen on any scale: a sprawling meadow, tiny balcony, or even single window box. If you have a balcony, you can create a pollinator garden entirely in pots. If you don't have any outdoor space at all, even window pots or boxes with flowering native plants can provide a valuable pitstop for pollinators flying through. Most people aren't aware of the link between medical prescriptions and insect life. But overuse of antibiotics and other medications was ranked in the top five emerging threats to pollinators. The clearest links to damage are from agricultural antibiotics, sprayed on fields. But human medications – huge amounts of which enter ecosystems through waterways – are also affecting many species, and are of growing concern for ecologists. No one should stop taking necessary medications, but you should use them only as directed, and dispose of them properly when out of date – don't just flush them down the toilet. Some butterflies rely on just a few plant species for food and reproduction. They also need variations in habitat, particularly scrubby areas with sparse, longer vegetation, shade from intense heat, and shelter. That's where butterfly banks come in. By creating a raised area of habitat that provides shade and natural variations in temperature throughout the day, butterflies have areas of refuge from unpredictable weather extremes. Many nature reserves and some farms are using them to help butterflies survive global heating. Recent trials have built the banks in an 'E' shape – if you have access to a larger garden or piece of land, you can do the same. While many harmful insecticides have been banned in food production, some remain legal for treating fleas in dogs and cats. A growing number of studies show that they are a disaster for wildlife, often leaching into waterways from fur. One monthly flea treatment for a large dog contains enough imidacloprid to kill 25 million bees, according to recent research. Avoid them altogether, or if you absolutely must de-flea, don't let your dog swim for at least a month after treatment. If you're planting for pollinators, knowing where to start can feel overwhelming. Many nature-loving gardeners advocate for the 3 x 3 x 3 method: pick three native plant species that flower in each growing season – spring, summer and autumn – and plant them each roughly in their own area. This way, you provide insects with food and habitat throughout the year. Here is a beginners' guide to getting started. While native plants in general will help, a smaller subset are absolutely critical for insects – particularly caterpillars – and the birds that feed on them. 'Just 14% of our native plants are supporting 90% of the caterpillar species in North America – we call them keystone plants,' Tallamy says – and the same applies to many other countries. After he rehabilitated his own plot of land with keystone species, Tallamy says, he watched the numbers of insects and birds shoot up. For the US, those keystone plant species are listed by region by the National Wildlife Federation. The UK also has lists of local keystone plants: native varieties of cherry, birch, and oak, for example, support 400 species of caterpillar each. In other regions, try searching for insect keystone species for your area. Of the world's more than 20,000 bee species, between 64% and 83% nest in the ground. Researchers from Australia conducted an experiment to find how native bees responded to different nest materials, and found that sprinkling rocks and gravel over the soil resulted in the greatest increase of nests. Different bee species need different environments to survive – you can speak to local bee conservation groups about specific ways to make gardens around you more nest-friendly for local and endangered species. There is very clear evidence that collapsing insect populations are driven by the rollout of intensive agriculture and pesticide use. If you can afford it, buying organic foods, which are produced without the use of synthetic pesticides, can help give space for insects to recover. 'Tiny plastic particles are everywhere and can reduce pollinator health and lifespan,' a new report on threats to global pollinators has found – ranking microplastics as the second most significant emerging threat to insects. All polyester, nylon, spandex and acrylic fabrics are plastic, and they shed millions of fragments as they're washed and worn – a single load of polyester-containing laundry can shed 700,000 microplastic fibres. Natural fibres, such as wool, silk and linen don't shed any (cotton also does not shed microplastics, but is responsible for about 4% to 10% of the world's pesticide and insecticide use – you could opt for organic cotton, which does not use synthetic pesticides). Likewise, reducing all of your plastic use – bags, packaging, bottles, toys – will help cut the microplastics you release into the world. Death and disintegration are part of the life cycle of ecosystems, providing vital food and homes for insects, and adding nutrients to the soil. Dead trees, fallen branches and logs – even small dead mammals – all provide important food for invertebrates. By clearing them away, we eliminate habitats and nutrients. If you can safely do so, let things rot. Herbicides and pesticides are one of the most significant threats to insect life. Glyphosate, one of the world's most common herbicides, has significant effects on insects, damaging their immune systems. Avoid blasting unwanted plants with chemicals and weed by hand instead – there is also research to indicate that spending time gardening is linked to better physical and psychological health. Insects are particularly sensitive to changes in temperature, which act as a trigger for stages of their lifecycle. But as global heating disrupts previously predictable weather patterns, these processes are increasingly out of sync. Creating cooler areas of shade – particularly when temperatures are abnormally high – provides shelter and respite for insects. No mow May is one of the most successful recent environmental campaigns in the UK, intended to provide more habitat to bees, butterflies and other invertebrates during a key part of their lifecycle when they are emerging from a cold, hard winter. But it doesn't have to be only May. Letting grasses grow uninterrupted, particularly where native wildflowers thrive, can be a big boost for insects. Sometimes, all a vacant plot, neglected berm or empty lot needs to boost its biodiversity value is seeds. Researchers from Poland recently found that patches of wildflowers in cities can be just as good for insects as natural meadows. By protecting and growing those patches, 'we can alleviate the hostile environment of urban space for wildlife', the researchers wrote. A number of NGOs distribute free native wildflower seed packs. You can even buy (or construct) your own sprinkling system: put a mix of seeds in a spice shaker, and carry it to sow flowering species in neglected spots of green. Research on insects has been troubled by a lack of good population data. To fill the gap, some researchers are turning to surveys by citizen scientists or local communities: one of the most influential, robust pieces of research on insect declines was a study that used data from amateur entomologists across Germany, and found insects in nature reserves had dropped 82%. You can volunteer for one of the butterfly counts now run across the UK, US, Europe, and many other parts of the world. Often, that involves just 15 minutes of counting butterflies in a nearby location. The UK also has the Buglife 'splatometer' survey, measuring how many bugs are squashed on vehicle number plates over time. Invasive species can be catastrophic for biodiversity. A single colony of Asian hornets, for example, can 'butcher' 90,000 UK pollinating insects in just one season. You can help control invasive species that haven't yet established breeding populations by learning what to look for, and reporting sightings to the relevant government department. The UK, for example, runs an Asian hornet-spotting app, and most US states have their own process for reporting an invasive species to their wildlife departments. While often hidden from sight, bats and some owl species feast on insects through the spring, summer and early autumn, and play a key role in regulating their populations. Where owls and bats disappear, farmers tend to increase their insecticides: a study last year found that when the local bat population died, farmers dramatically increased chemical pesticide use. By supporting your local bat and owl populations, you can have positive knock-on effects for insects. 'We're at a new point in human history,' entomologist David Wagner says, where the heating planet has become the biggest threat to insect life across the world. Up until the last decade, 'the major drivers of biodiversity losses around the planet were really land degradation and land loss, habitat loss. But I think now, that climate change is by far exceeding that,' Wagner says. Stopping the worst of global heating – and saving trillions of insects – requires us to dramatically cut our use of fossil fuels. Find more age of extinction coverage here, and follow the biodiversity reporters Phoebe Weston and Patrick Greenfield in the Guardian app for more nature coverage
Forbes
20-05-2025
- Science
- Forbes
Climate Change And Land Use Changes Threaten Native Bee Populations
Warming temperatures at night combined with habitat destruction are the cause of large population declines in wild native bee populations. The world's insect population is collapsing, with more than 40% of all insect species facing extinction (ref). The most affected insect groups include our old friends, the butterflies and moths (Lepidoptera), bees and wasps (Hymenoptera) and dung beetles (Coleoptera). This impending collapse poses grave threats to global food security, to the proper functioning of global ecosystems and to global biodiversity, and is particularly severe for solitary bee species, which are especially sensitive indicators of ecosystem health. A recently published study reports that the complex interplay between climate change and human land use – agriculture and urbanisation – is the main problem underlying the rapid decline of insect populations. Already, scientists report that intensive agriculture is the main driver of population declines in unrelated animals such as birds and insectivorous mammals. But how do land use changes and climate change interact with each other to impact insect communities in different habitats? To better answer this question, ecologist Cristine Ganuza, a postdoc at Julius-Maximilians-Universität Würzburg, and a large team of scientists from the University of Bayreuth, the Technical University of Munich, and Weihenstephan-Triesdorf University of Applied Sciences, collaborated to investigate how the effects of warmer temperatures act in concert with intensified land use practices. Using several field survey methods, the researchers examined 179 plots in 60 study regions across Germany. These plots comprised one of four habitat types: forest, grassland, arable land and human settlements (Figure 2, also see Figure 3). As they predicted, Dr Ganuza and collaborators found that pollinator diversity increased as human land-use intensity declined (also ref). The researchers also found that bee populations living in forest environments were extraordinarily resilient to the stresses of warmer days; surprisingly, increased daytime temperatures in these natural landscapes even correlated with higher bee abundance and diversity. Unfortunately, this beneficial climate warming effect was not seen for bees living in urban settings, where their numbers plunged by 65%. This finding highlights the detrimental effects of excessive heat combined with habitat destruction. But what specifically was harming the insects? Although bees are active during the day when it's generally warmer, Dr Ganuza and collaborators found that warmer nighttime temperatures, particularly when combined with urbanization, were harmful, creating 'climate traps' where bees and other insects struggle to survive despite environmental protections. Further, warmer nighttime temperatures consistently diminished both the richness and abundance of bees across all habitat types investigated. This is especially worrying because global climate change is increasing nighttime temperatures faster than daytime temperatures. 'The fact that night-time temperatures have such an impact on diurnal insects is significant. Precisely because average night-time temperatures rise even faster than daytime temperatures,' Dr Ganuza said. Do hot nights affect bees in the same way they affect humans? Are they, like humans, unable to sleep on a hot night, making them unable to function at their best during the day? Or are they dying during the night because of the heat? 'We do not find it likely that they die from excessive heat during the night,' Dr Ganuza replied in email. 'However, the problem is worse for bees than for humans. This is because bees are ectothermic organisms, which means that they cannot regulate their body temperatures as we humans do.' 'Bee metabolism is determined by external temperature conditions,' Dr Ganuza explained in email. 'Therefore, warm nights might keep bees metabolically active when they should be resting. This could stop their bodies from recovering properly, and a high metabolism can also consume fat (i.e. 'energy') reserves.' Dr Ganuza emphasized the importance of this insight because it helps scientists understand how physiological stresses during rest periods may undermine daytime activity and survival. 'While this is just a hypothesis, we do know that flying takes a lot of energy for bees,' Dr Ganuza continued. 'If they are tired and weak after a hot night, they might have trouble foraging for food and could be more likely to get eaten by birds or other animals.' In short, understanding how these climate change and land use changes operate in concert will be pivotal for developing conservation strategies that buffer insect populations against rapid climatic changes. A bumblebee in flight. (Public domain) Public Domain Dr Ganuza and collaborators found that the combined stresses of climate warming and land use intensity did vary across insect trophic levels. On one hand, insects higher in the food chain – predatory insects – showed a greater tolerance to elevated temperatures but, on the other hand, they were harmed by simplified landscapes that are devoid of natural vegetation – agricultural fields. This study's findings have important implications for agriculture and land management practices because many predatory insects play a critical role in natural pest control. This damaging effect can be somewhat mitigated by maintaining a mosaic of farmland interspersed with natural habitats that are suitable for supporting insects that are crucial to sustainable food production. Additionally, the study's findings advocate strongly for the protection and restoration of heterogeneous landscapes that maintain connectivity between forest and grasslands, thereby allowing native insects to move around between these natural habitats. Therefore, the preservation and creation of interconnected natural habitats within agricultural and urban areas is of great importance. Such measures are critically important because pollinators and predators respond differently to environmental stresses and to increasing nighttime temperatures, and these differences may upset the balance between these groups of insects that are crucial for proper ecosystem function. Such an imbalance could end up threatening vital ecosystem functions such as pollination and natural pest regulation, which are the foundation for both biodiversity and human agriculture. Probably the most worrying finding is the implication that even subtle climatic shifts can amplify existing human pressures on ecosystems in complex and unexpected ways. For example, as environmental temperatures continue their upward trajectory, understanding the intricacies of insect responses – especially among critical pollinators like bees – will be essential for safeguarding global food security and, indeed, for protecting life on Earth. Dr Ganuza and collaborators meticulously documented how the interaction between climate warming and land use forms a complex web of threats that cannot be addressed in isolation. Dr Ganuza and collaborators' meticulous study calls for urgent, nuanced responses to insect declines that take into consideration the synergistic effects of climate warming and land-use change, to prevent more irreversible losses to biodiversity and ecosystem services. Cristina Ganuza, Sarah Redlich, Sandra Rojas-Botero, Cynthia Tobisch, Jie Zhang, Caryl Benjamin, Jana Englmeier, Jörg Ewald Ute Fricke, Maria Haensel, Johannes Kollmann, Rebekka Riebl, Susanne Schiele, Johannes Uhler, Lars Uphus, Jörg Müller and Ingolf Steffan-Dewenter (2025). Warmer temperatures reinforce negative land-use impacts on bees, but not on higher insect trophic levels, Proceedings of the Royal Society B: Biological Sciences 292(2046):20243053 | doi:10.1098/rspb.2024.3053 Cristina Ganuza, Sarah Redlich, Johannes Uhler, Cynthia Tobisch, Sandra Rojas-Botero, Marcell K. Peters, Jie Zhang, Caryl S. Benjamin, Jana Englmeier, Jörg Ewald, Ute Fricke, Maria Haensel, Johannes Kollmann, Rebekka Riebl, Lars Uphus, Jörg Müller, and Ingolf Steffan-Dewenter (2022). Interactive effects of climate and land use on pollinator diversity differ among taxa and scales, Science Advances 8:18 | doi:10.1126/ © Copyright by GrrlScientist | hosted by Forbes | Socials: Bluesky | CounterSocial | Gab | LinkedIn | Mastodon Science | Spoutible | SubStack | Threads | Tribel | Tumblr | Twitter
