What If We Lose Half Our Birds?

Birds are all around you, even if you live in the depths of the city and sometimes they feel like an abstract concept with the exception of the ubiquitous city pigeons. They’re a beautiful and diverse and splendid and amazing part of the natural environment, whether they’re soaring eagles or tittering sandpipers or songbirds that whistle merrily in the morning — there’s a reason we talk about the birds chirping in the morning, why birdsong is the part of so many idealised Disney moments. Culturally, we associate birds with some sort of happiness, freedom, beauty — and that’s before their important ecological role.

They snap up insects, snails, slugs, and other pests. They eat fish, and small rodents. Building homes for owls around your home can help keep the rat, mouse, and vole population down, reducing food spoilage and interference with the garden. Vegetarians gobble down fruits, nuts, and seeds, spreading them across the landscape as a result — some plants have in fact evolved side by side with birds and their seeds need to go through the digestive tracts of birds to germinate. Everywhere, birds are playing a vital role in the ecosystem, digging in to the environment and interacting with other animals and plants.

What would the world be like, then, if we lost half our bird population? It’s not exactly a hypothetical question, as a report from the National Audubon Society revealed in September. Within the century, we¬†can expect fully half of the native bird species in North America to be disrupted by climate change, including rare, unusual, and endangered species that may disappear entirely. That’s going to change the landscape forever, adding to the already serious changes that will happen as a result of climate change — and possibly compounding the environmental devastation being created as the globe shifts radically.

Several issues are contributing to the pressure on bird populations. Many bird habitats rely on a very narrow range of normal climate conditions — and we’re not talking about rain and sun from season to season, but larger trends. Raise or drop temperatures by a degree, and plants can fail to thrive. Push prevailing wind patterns around, and seeds may not be carried far enough, or a landscape may become too windy. Deplete water supplies as a consequence of inadequate rain, and a region will be looking at drought and poor conditions for many native plant species as well as birds — waterbirds, of course, will be nowhere to be seen.

It’s not as simple as pushing birds into a new habitat. You can’t teach an old dog new tricks, as they say, and that’s an actual truth for bird species, which typically evolve to live in very close association with their natural environment. They’re used to specific plant and animal species where they live, to particular temperatures, to given moisture levels. When the climate starts changing around them, they can’t keep up — and there may be nowhere for them to go, as no habitat will have conditions that match those of their old home. That leaves birds with limited options, particularly when their habitats are already being crunched by human encroachment, which makes it hard for them to seek refuge.

By 2080, the report warns, roughly half of the birds in the US will be facing significant disruptions because of our changing climate. While some will move on, adapt, and adjust because they’re hardy species or happen to find the sweet spot, others will not, and may be facing extinction. This includes not just threatened and endangered species, which are particularly vulnerable thanks to their low numbers, but also other, established species that simply won’t be able to adapt as their habitats change in response to the shifting climate.

It’s impossible to estimate which species will be most affected, and how many could be lost entirely. With over 600 bird species in North America, researchers can make some estimates based on past records, known bird populations, existing research, and climate trends, but it’s difficult to tell exactly how many birds will be involved and what their new lives will look like. While we may not ‘lose’ half our birds in the sense that they simply vanish, their role in our lives will be changing, and that will have a ripple effect on the natural environment, not just our birdwatching life lists.

Evidence suggests that some of the damage we have already inflicted on the planet is irreversible, and that if decisive action is not taken within the next few decades, even more of it will become so. With the evidence of the potential ramifications of climate change mounting, the West (most responsible for anthropogenic climate change) is still failing to take action on the issue, preferring to doom the planet to costs that could be extremely high — we may be looking at mass extinction events, at fundamental changes in our way of life, at a planet that becomes functionally unsurvivable.

Losing half our birds isn’t about not seeing a given species at the bird feeder. It’s about the huge, spreading cost of allowing North America’s climate to shift so radically that it’s fundamentally changing the environment for hundreds of plants and animals. And it’s about the snowballing results of these changes — today, this, tomorrow, that, and each day after that, more and more.

Many members of the bird community are concerned about climate change because they know it will affect global bird populations, and because they’re worried about the planet at large. The same goes for many other enthusiast groups and organisations that surround various other species. It would seem that the humble person with binoculars out on the shores of the lake early in the morning jotting down notes cares more about the environment than your political representatives do. What will it take to change that?

Image: Swan on golden water, glacierman, Flickr.