Birds are building nests with our rubbish. Can we offer them something better?

It’s spring, and Australian birds are building their nests. But with what? Alongside grass and twigs, birds are collecting our rubbish. In 2023, a global study found litter in the nests of 176 different bird species, with common culprits including cigarette butts, plastic bags and fishing nets. The risks these materials pose for birds – and particularly chicks – include choking, poisoning and entanglement. In Australia, birds are already doing it tough, with a biodiversity crisis and the arrival of bird flu. People might wonder: what can be done to help our feathered friends? One approach is to try and make better nest-building materials more readily available to birds, particularly at this crucial time of year. Our experimental project Peckable Architecture is designed to do just that. This month, as part of the Melbourne Fringe exhibition Design x Nature, 100 bricks made from natural nesting material have been installed across two prominent Melbourne sites: Federation Square and the Royal Botanic Gardens. Each brick combines bark, casuarina needles, fine twigs, coconut fibre and moss with an organic gelatin binder. The aim is for birds to collect the nesting materials they need as the bricks break down over time. Bethany Kiss, the creator of Peckable Architecture, is a designer and researcher whose practice explores the relationship between buildings and wildlife. Fred Kroh/Royal Botanic Gardens Victoria Birds are architects Birds nests are extraordinary creations; intricate webs of natural materials coming in all shapes and sizes. Fairy wrens build domed nests, willie wagtails make open cups, and apostle birds build deep mud bowls reinforced with dried grasses, in tree forks. In designing their nests, birds respond to the natural environment in ingenious ways. A study of more than 700 nests held in museum collections found that those from rainy places had thinner walls to dry out faster, and open cup nests from windy places were often deeper, to keep eggs from blowing away. As their local environments have changed over time, birds have adapted, incorporating human-made materials. A study of 893 nests from Australian museum collections, representing 224 species, found the occurrence of human-made materials in bird nests rose from 4% in 1832, to 30% in 2018. Most of these additional materials were plastics. In Europe, researchers documented crows and Eurasian magpies building nests with anti-bird spikes. Ironically, the magpies placed the spikes pointing outwards, possibly to keep other birds away. Magpies’ nest made from anti-bird spikes. Photo credit: Auke-Florian Hiemstra, Naturalis Biodiversity Center. The risks of rubbish use Avian resourcefulness often comes at a cost. String, fishing wire and plastic twine frequently make their way into nests, where they can wrap around birds, trapping or choking them. In Portugal, a study on white storks found 91% of nests included human-made materials. Over a period of weekly monitoring, 12% of the nestlings became entangled, most commonly in baling twine. The damage from human-made materials can also be less visible. In Mexico, house finches line their nests with cigarette-butt fibres, which repel nest parasites – themselves a significant threat to birds and particularly chicks. A study found that while nests with cigarette-butt fibres resulted in better hatching and fledgling success, the chicks showed increased signs of genetic damage. The Litter Bird-en project invites members of the public to share images of birds interacting with human-made materials, making the prevalence of the problem more visible. Ursula Dutkiewicz/Federation University Australia, CC BY-NC Birds need our help Birds are already struggling. One in six Australian bird species are nationally threatened, with land clearing, cat and fox predation and changes in climate the most serious threats. Compounding this is the H5N1 strain of bird flu, which was detected in Australia for the first time in June. Since arriving in Australia, bird flu has already caused mass mortality events and there are legitimate fears it will accelerate the biodiversity extinction crisis. Now more than ever, we need to help ease the pressures our birds are facing. Designing with animals in mind Our cities shape what birds can find to build their nests. When gardens are cleared of fallen leaves and twigs or paved over by concrete or lawn, birds lose access to precious nesting resources. Peckable Architecture asks what the built environment might look like if we designed it with bird welfare in mind. Our bricks use materials that local birds in Melbourne, such as superb fairy wrens and grey fantails, typically use. At the installation sites at Fed Square and Royal Botanic Gardens, we’ve installed motion-activated cameras to record which bird species visit and which materials are taken away. Peckable Architecture’s bricks are made with natural materials that native Melbourne birds are known to prefer. Fred Kroh/Royal Botanic Gardens Victoria What you can do at home Let leaf litter, bark, grasses, and twigs build up in parts of your garden, and leave spider webs where you can. Many small Australian birds, such as fairy wrens and grey fantails, use web silk to bind their nests together. You can also put out natural materials such as dried grass, short lengths of coconut fibre, straw and bark. Skip anything long and stringy, which can easily tangle around chicks. Dryer lint is also not a good idea as it can fall apart and release chemicals. Pick up rubbish where you can, especially hair ties, fishing line and cigarette butts. If you see a bird tangled in rubbish, contact your local wildlife rescue service. Birds build their nests with whatever they can find. This spring, let’s make sure some of those materials are as nature intended. Find Peckable Architecture at Royal Botanic Gardens and at Fed Square (The Test Garden on the car park roof) in Melbourne CBD until October 18 as part of the Design X Nature exhibition.