Ecosystem destruction: human impact on bird extinction and consequences for global biodiversity throughout history

The research shows that human activity over the millennia has led to the extinction of more than 600 species of birds, and the consequences of these losses are far-reaching and significantly impact global ecosystems. Along with the extinction of individual species, specific functions performed by these species in nature are also disappearing. Birds like hummingbirds, which play a crucial role in pollinating plants, are no longer present, creating chain reactions throughout entire ecosystems. Another species, like vultures, helps recycle dead organisms, and their extinction causes an increase in disease levels due to inadequate removal of dead material.

The loss of birds, which were key to ecological functions such as seed dispersal, leads to a decrease in biodiversity and the capacity of plants to adapt to climate change. For example, birds on tropical islands played particularly important roles, as they developed specific adaptations in isolated habitats. With the extinction of these species, entire ecosystems on islands begin to decline, a phenomenon particularly noted after 1500 when European colonizers introduced invasive species such as rats, cats, and pigs that rapidly spread and destroyed local fauna.

It is estimated that around 1,300 bird species could disappear in the next 200 years if current trends continue. These extinctions will not only affect species abundance but will also dramatically reduce functional and phylogenetic diversity within ecosystems. For instance, the loss of these species diminishes flower pollination, seed dispersal, insect population control, and scavenging, all of which have far-reaching consequences for the sustainability and resilience of ecosystems on a global scale.

Ecological importance of birds

The role of birds in ecosystems is not limited to their abundance but also to their functional diversity. Each bird has its specific ecological niche and helps maintain balance in nature. Hummingbirds, for example, serve as pollinators, while species like vultures remove dead organisms and reduce the potential spread of disease. When these birds disappear, entire ecosystems become endangered, creating a domino effect in nature.

On islands, the loss of birds has a particularly strong impact because these birds were often the only species performing certain functions within local ecosystems. For example, the extinction of the dodo bird on Mauritius led to the extinction of several species of insects that fed on dodo bird droppings. This clearly shows how each bird loss is connected to the loss of other species within the same ecosystem.

The urgency of bird conservation

Scientists emphasize the importance of urgent action to prevent further bird extinctions, not only because of their ecological roles but also due to the loss of billions of years of evolutionary history. Each extinct bird species carries with it a unique branch of the evolutionary tree, and with its disappearance, that evolutionary heritage is also lost. This loss of phylogenetic diversity has dramatic consequences not only for biodiversity but also for the resilience of ecosystems to future changes, including climate change.

Despite ongoing efforts to conserve and restore bird populations, it is projected that the global extinction trend could lead to the complete disappearance of hundreds more species in the coming centuries. Therefore, targeted conservation actions are needed to preserve remaining species and protect the ecological functionality of ecosystems worldwide. These actions include habitat restoration, reintroducing extinct species, and implementing species protection programs for those on the brink of extinction.

Source: University of Birmingham