Bird feeders are good for some species but may be harmful for others


I.In May 2020, when the first wave of the COVID-19 pandemic erupted in Texas, I went to a nature store in Austin and bought a few bird feeders. The birdsShortly thereafter appeared, extracted from seeds and nightingales. They flew down from the walnut trees and telephone wires: bold crested tits, bouncing northern cardinals, and mocked crowds of white-winged pigeons, house sparrows, and European starlings.

I was not alone. Feeders have long been a popular way to connect with nature and attract native species and migrants for our instruction. In 2018, the US has already made $ 4 billion from the global bird feed market from $ 5 to $ 6 billion. But over the past two years, the popularity of bird feeding has increased – nonprofits, including the Audubon National Society, reported record sales in 2020 of their feeders and licensing programs for wild birds, and some bird shops marked a 50 percent jump. in demand. As more and more people began to watch the birds, many, like me, did so by putting up a feeder.

The benefits of all this provision tend to remain undeniable. After all, habitat destruction as a result of human activity is a major cause of declining bird populations, so feeding birds seems an obvious way to compensate for this loss. But a recent review published in Biological conservation is a worrying possibility: feeding birds may change some local environments – and squeezing out some species of birds such feeding should help. “If you dump millions of tons of extra unnatural resources into the environment, you’ll get huge, massive impacts,” said lead author Jack Shatt, a conservationist and conservationist at the University of Manchester in England. “And they won’t always be what you expect.”

Feeding birds carries several well-known risks. Chief among these is disease transmission. This conclusion was reached by scientists in 2005 common feeders in the UK may have helped pigeon trichomania – opportunistic and nasty parasitic infection –jump in European greens, after which it reached epidemic levels and killed up to half a million birds. In the US trichomania and salmonella outbreaks associated with dirty feeders are common killer birds. “You have different species that peck at the same plastic that is covered in different biological fluids of birds,” says study co-author Alexander Lis, an ornithologist. at Manchester Metropolitan University. “It’s a recipe for disaster.” (When a mysterious disease struck birds in several states last summer—because of which officials asked poultry farmers to remove the feeders– The conclusion that the feeders were ultimately not to blame came as a surprise to many experts.)

But a number of studies conducted in the UK suggest that the effects of extensive supplementation may be much deeper than disease transmission. Although the U.S. is the world leader in pure seed consumption, the densely populated UK is one of the world’s most dedicated bird-feeding crops, Fox says. About 64 per cent of British households produce poultry seeds – about 165,000 tonnes – enough, according to one study, to maintain three times the population of the most common types of feeders on the island. Indeed, another study found that seed feeders can recover as much as 75 percent the daily diet of an individual British tit. A third study has found that feeding in the UK Blackcaps can be an incentive speciation event between birds that fly to continental Europe and those that stay near the feeders in winter.

These studies prompted Lisa and Shatta to take a closer look at the literature on bird feeding to find clearer links between feeders and their impact on the wider ecosystem. What they found was alarming. According to them, as feeding has grown over the past 25 years, the population of adapted and aggressive station wagons – great tits, Eurasian slugs and invasive ringed parrots – has risen sharply by 40, 83 and 1,480 percent, respectively. At the same time, forest species that avoid feeders, such as forest reeds and marsh tits, have declined sharply. Willow tits are increasingly losing their nesting holes due to blue tits that use feeders, and are losing hatching to hungry great spotted woodpeckers, another species that uses feeders, which have grown nearly 150 percent in the past 25 years. Over the same period, the willow tit population in the UK has declined by 87 per cent. In fact, researchers say, the commercial feeding industry in the UK seems to have helped aggressive broad-based professionals adopt whole bird communities and pour out of the gardens into the unsecured deserts.

Seeds are eaten not only by birds: bird feeders can feed the population of rodents and foxes, increase nest predation and may cause other as yet unknown consequences. In Australia and New Zealand, where invasive species have wreaked havoc on local ecosystems, such concerns have forced conservation groups to take a much colder stance on the occasional feeding of birds.

Shat suspects that these types of indirect feeding effects – increased rodent numbers and altered ecosystems – are likely to be much more common than previously thought. “The processes are similar, regardless of the individual species involved,” he says. “Once you give a huge amount of resources to a select group, not their competitors, you will knock out their competitors.”

However, whether bird feeding has these alarming effects in other parts of the world remains largely unknown. For example, the United States tends to feed less intensively – and less densely populated – than the UK, and therefore may not change the fate of birds so dramatically. But real field research remains insignificant. “We don’t quite understand the indirect effects of bird feeding,” says Emma Greig, project manager for Project Feederwatch, a civilian research program affiliated with Cornell University. The program has tracked some of these effects, she says, including a 2017 study that potentially links expansion of the winter range in the species of the West Coast hummingbird to the wider use of homestead nectar feeders. But Greig is hesitant to draw too many conclusions about the impact of bird feeding in the U.S. from British research. “The story about tits in England will definitely be about creeps in Michigan. Therefore, the repetition of such issues in different systems, I think, will be very important, “she said.

The question of how bird feeding affects ecosystems desperately needs further research, says James Rivers, an environmentalist at the University of Oregon. “It’s very surprising to me how limited the data is,” Rivers said. The last few decades of this practice are essentially a global environmental experiment, he notes, with impacts that can be as profound as reintroduction of wolves to Yellowstone National Park, which defeated elk herds, increased beaver populations and changed the wood composition of forests. Although the changes in Yellowstone were mostly positive, they were also far-reaching and unexpected.

But studying the environmental impact of feeding our feathered friends will require decades of projects and complete American datasets that don’t yet exist. “A study of these indirect effects [in American species] lagged behind relatively direct consequences, ”such as disease transmission, Rivers says,“ because looking at a community of organisms interacting in natural circumstances is incredibly difficult ”.

In both the US and the UK, the wider bird community doesn’t seem willing to ask too many questions. Supplemental feeding is often sold to consumers as a way to contact local birds and help them. But behind these reports of well-being lies a multibillion-dollar industry whose environmental footprint is in terms of carbon, transport and land use costs-requires serious attention, says Lis. And yet conservation organizations such as Audubon, carefully involved in the industry, sell specialized seeds and licensed feeders, and partner on projects with companies like Wild Birds Unlimited. Conflicts of interest that arise may be unconscious, but they are present no less. (Wild Birds Unlimited did not respond to requests for comment.)

To complicate matters further, feeding birds has some undeniable benefits. As Greig and Lees point out, this encourages people in more urbanized and developed areas, where it is harder to find natural food sources for birds, to interact with birds. Indeed, supplementary feeding can be anything that supports endangered species in human settlements, such as house sparrows and European starlings – species that are not native to the United States and are often considered pests, but the number of which is at its most the matter is declining in the world.

What is needed, Fox says, is to take the potential impact seriously enough to encourage further study that would allow experts to give much more detailed advice on where to feed and where to avoid it. Such research can also help researchers provide targeted advice on what foods to offer.

“I think in the future it should be more scientifically sound, focused, because you can’t just pour resources into the system and not expect these cascading effects,” says Lis. “I am not saying that all this should be abolished immediately. But I think it is necessary to understand what is happening. “

Meanwhile, if you have land, there are other ways to help wild birds that are independent of the feeder (although if you have a feeder, it should be removed and cleaned dilute the bleach solution every two weeks; most people don’t). Greig suggests leaving the leaves untouched or parts of the lawn unmown and occasionally creating a bunch of bushes. Less intensive land management increases the population of local insects, which in turn attracts local birds such as sparrows, juveniles and feline birds.

Then there is gardening – planting only local wildflowers and shrubs, nectar, fruits and seeds of which attract local birds. Although it is easier to do in an unpaved yard, planting a variety of herbs and flowers in mobile garden boxes will also help even on the balcony of the apartment. Easily available fresh water – from a refined pond or from a well-groomed, bubble bird bath – will also attract your share of birds. (I say from experience: after installing an 18-gallon plastic pond in my backyard last year, clouds of cedar waxwings and big-tailed astrakhan came to drink and swim.)

“You are essentially introducing natural resources into your diet, not imported and non-native goods,” says Shatt. Although these natural resources may attract less bird density than bird feeders filled with non-native seeds, this means that emerging birds receive “normal, positive amounts of food for this environment,” he says. .

“Making your garden useful to wildlife is a million times better than feeding 10 common bird species” commercial bird food, Fox says. After all, local plants are important for a cohort of insects, reptiles and mammals. “You create a resource that doesn’t require you to keep coming back and buying bird seeds. And [you’re] creating something that could potentially stay after you, as opposed to feeding, which is a very consumer model of helping birds ”.

These days I only have one bird feeder. In the yard of my lease I built several garden boxes, sowed them with local flora and scattered among them piles of logs for fencing lizards and nettles. I maintain bird baths and let the leaves go where they want. I write, I look out the window at the garden, and there is a fuss. The flowers are waving. The lizards are running away. And the birds are still arriving.

Bird feeders are good for some species but may be harmful for others

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