“Land Use Changes from a Bird’s-Eye View”

A Unique Perspective on the World's Changing Environments

Imagine the unique perspective migrating birds have of the Earth. Each year they fly thousands of kilometres across entire continents covering the vast expanse of the planet, its many different climates and landscapes.

This unrivalled view also enables them to notice the dramatic changes which are currently threatening many of our planet’s ecosystems. Each year more and more of the sites migratory birds depend on during their journeys disappear. As these ecosystems change, there is no guarantee that the habitats migratory birds need along their migration path, will be there the next time they return.

Looking at the world's changing landscapes from a "bird's eye view" is a valuable perspective and can help reveal humankind's dramatic impact on the global environment.

The majority of these changes are caused by human use of land and have a direct impact on migratory bird populations, which are particularly sensitive to any interference to the sites they use throughout their migratory cycle.

Through their dependence on many habitats along their migrations, birds often feel the effects of these changing environments first before many other animal species, making them key indicators for the health of our environment. By focussing on "Land use changes from a bird's eye view" World Migratory Bird Day 2011 aims to highlight the negative effects human activity is having on migratory birds and our global environment.

The Human Hand

Harmful Changes to Migratory Bird Habitat Are Likely the Result of Human Land Use

Human land use is the greatest threat to migratory birds because it profoundly contributes to the loss of migratory bird habitat. Consequently it is the overwhelming reason for the declining populations and extinctions of migratory birds. Of all the threats to migratory birds, the “Human Hand” effect on the Earth’s natural environments is the greatest. The Human Hand, or the way humans change and use the natural world for their needs, is the greatest threat to migratory birds because it directly changes, degrades, fragments or removes the habitats migratory birds need to survive.

It is undeniable that the world looks drastically different from how it did even one century ago and that this transformation is the result of human activity.

These changes are the direct result of human use of land, as humanity must necessarily change and use natural environments, such as forests, wetlands and grasslands, to sustain its need for food and shelter. But the rate and global scale by which humans now change natural environments risks altering them too much, to the point where it is no longer sustainable.

Migratory birds are a good indicator of how humans interact with and use the natural environments around them. Migrating birds connect all of the continents and oceans of the world, and protecting these birds, by protecting their habitats can also benefit other plant and animal species. Furthermore, protecting migratory birds and the habitats they need to survive can also help ensure that the natural world will continue to provide for future human generations.

Different Land Uses and Migratory Birds

Certain Land Uses are More Damaging than Others

Certain land use changes have a particularly profound impact on migratory bird populations, as they are extremely damaging to the birds’ critical habitats.

For example, urbanization and intensive agriculture can fragment and replace complex networks of habitats needed by the birds. Deforestation and mineral extraction can damage entire regions used along the birds’ annual migration paths. In addition, land reclamation and biofuel production remove or degrade crucial wetlands and other habitats for many migratory bird species.

While human survival depends on these transformations of natural areas, a sustainable use of land is vital to reduce the impacts on our natural resources, such as water, soil, nutrients, plants and animals – including
migratory birds.

Deforestation

Deforestation removes, degrades and fragments large areas of habitat crucial to the survival of many migratory bird species. These forests, such as the Amazon in South America, are important habitats where some migratory birds stay when it is too cold at northern and southern breeding grounds. The loss of wintering habitats is thought to greatly contribute to the continuing decline of migratory birds that migrate to tropical forests. [ read more ]

Urbanization

The consistent growth of cities and urban networks can disrupt the intricate chain of habitats birds need to complete their migrations. The steady expansion of cities and increasing urban development often leads to the destruction or replacement of productive natural habitats which migratory birds use as resting, feeding and breeding areas during their migration. Dense regions of urban development such as in Europe have resulted in the loss of many of these connecting habitats, making migration for birds increasingly difficult. [ read more ]

Land Reclamation

Land reclamation often entails filling in critical bird areas such as wetlands and estuaries for the extension of cities and agricultural lands. Yet these wetlands are biologically extremely productive habitats, which often support millions of birds a year. Despite the relatively small size of these areas, the loss of these important habitats can have dramatic affects on many migrating bird species at once. [ read more ]

Mineral Extraction

Mineral extraction can harm the sensitive ecosystems migrating birds depend on through damaging habitat and pollution. Not only do mines often physically remove large areas of habitat, (sometimes even eradicating entire mountains and lakes); some extraction processes can use and pollute limited water supplies from local wetlands. These pollutants affect food webs and productivity, damaging the natural environment’s ability to support migrating birds. [ read more ]

Intensive Agriculture

Intensive agriculture differs from other types of agriculture because of its magnitude and use of chemicals and pesticides. Large-scale intensive agriculture creates vast regions of featureless landscapes, replacing water sources and diverse food webs with crop monocultures. These monocultures break up and fragment habitats used by migrating birds, making it increasingly difficult to complete migration through vast areas of intensive agricultural regions. [ read more ]

Biofuel Production

Increasing demand for ecologically friendly fuel has dramatically enlarged bio-fuel production. Yet in regions of water scarcity such as in Africa, many bio-fuel farms are built on biologically rich areas for their abundance of water and nutrients. Migrating birds depend on these “oases” amongst vast regions of land not productive enough to support them. [ read more ]