Being common is not the same as being safe. Londoners once used the expression “common as sparrows”. These days, you can walk the length and breadth of the capital without seeing a single house sparrow. In North America, passenger pigeons used to darken the sky and a flock would take hours to fly over. The last one died in Cincinnati Zoo in 1914. Her name was Martha. Over the course of the last two centuries we have seen that a species that exists in vast numbers has no guarantee of survival, and we’re seeing it again now with the yellow-breasted bunting.
The decline of the yellow-breasted bunting is shocking. Since 1980 the population has fallen by 90% and its range has retracted by 5,000km. Once spread out over vast areas of Europe and Asia, from Finland to Japan, the bunting, sometimes known as the rice bird, is no longer present in eastern Europe, European Russia, large parts of western and central Siberia or Japan. It has gone, in the space of a human generation, from ubiquity to scarcity. Dr Johannes Kamp of the University of Münster, writing in the Journal of Conservation Biology, said: “The magnitude and speed of this decline is unprecedented among birds distributed over such a large area, with the exception of the passenger pigeon.”
Like the passenger pigeon, it has been sent into decline by hunting on an industrial scale. Both became major target species because of their apparently limitless abundance. Yellow-breasted buntings used to form huge flocks during migration. They would make evening roosts with thousands of birds on every branch, dozens on every twig. They were taken for food with a classic plenty-more-where-that-came-from attitude, netted and trapped in astronomical quantities. It’s reckoned that, in China’s Guangdong province alone, 1m buntings were consumed each year during the 1990s. Protective legislation was introduced in China in 1997, but there is a thriving black market in buntings. It reflects a wider issue faced by all common Asian birds: that solutions are never as fast-acting as problems. It frequently takes unfeasible amounts of time before a problem is even acknowledged.
But we have at least reached that stage. This year, conservationists in China, Japan, South Korea and Russia have agreed that something needs to be done. An action plan will be set up under the Convention on Migratory Species, established by the United Nations in 1979 to protect species that don’t confine themselves within national boundaries. There are now steps being taken for education and enforcement. In China, birdwatchers are being called on to look out for bird-trapping. Birdwatching is becoming more popular in China and most centres of population now have a local birding group. There is even one in Shenzhen, so famous for its nightlife that it became known as “the overnight city”—perhaps the world’s least obvious place for birdwatching.
Behind the species-specific story of the yellow-breasted bunting is a greater and more wide-ranging issue, and one that doesn’t often get mentioned. The notion of biodiversity is known and accepted across the world, so much so that modern wildlife conservation is frequently seen as an exercise entirely restricted to maintaining the current number of species. But this ignores bioabundance, a term coined far more recently.
The idea behind the word is that the conservation of a token number of each species is not enough. Abundance is also critical, not just in terms of spectacle or even in the wider context of predator-prey relationships, but because some species simply can’t cope when the population falls below a certain level. The passenger pigeon was perhaps one of these, and a similar phenomenon may be behind the catastrophic decline of London sparrows. The plight of the yellow-breasted bunting shows that bioabundance may be as important as biodiversity. And biodiversity is the mechanism by which the planet operates.