Loss of habitat is becoming all too common for species around our planet. Historically, normal changes in climate occur and species become extinct. Many of these extinctions occur undetected. This UN article from 2007 may seem dated but it really is not. Looking forward from that year and we begin to see an increase in the disappearance of vital stop-over points for migratory birds – especially, those traveling for long distances.
Climate shifts throughout history have occurred gradually and bird species were able to adapt. Today, human-induced climate change is forcing behavioral shifts in migration versus evolutionary shifts. Over long periods of time, birds gradually recognize that change is coming and begin to search for adaptive strategies. Shorter-term changes occurring rapidly force habit changes that do not allow for these gradual, adaptive shifts in behavior to occur.
“Climate change is likely to impact migratory birds in a number of different ways. Increased storm frequency, lowered water tables, higher drought frequency, sea level rise and habitat shifts resulting from climate change could all have a dramatic impact on migratory birds.”
The example used in the UN article is the black stork.
“The long journey to his non-breeding grounds south of the Sahara desert was arduous. The majestic bird is desperately looking for a place to rest, where he can recover and refuel until taking up his journey to return to his breeding grounds in a few months time. But instead of water and wetlands, which were once common across the region, all he sees is sand and dust. Gradually his black wings flap more slowly and his tired eyes continue looking for a place to rest – in vain.
One of the major effects of climate change is the loss of habitats. The habitats migratory birds depend on are in danger to change and to disappear due to increasing temperatures, flooding or desertification. Coastal wetland areas that migrating birds use for nesting and foraging are an example. During their migration, birds rely on these areas to provide food and resting places. There they can refuel and repose before continuing their long journeys. Rising sea levels due to climate change cause the flooding of these habitats and they are lost for birds and other animals. Without these stop-over places, the birds have insufficient reserves to continue and have difficulties completing their journeys.
The loss of habitats continues through increasing desertification for example of the Sahel region. Increasing populations lead to a demand for more land to grow crops and graze animals and to the intensified use of land. This contributes to further land degradation and leads to expansion of desert areas. Climate change worsens the effect by a decrease in rainfall in the Sahel region.
Increasing temperatures, changing vegetations and extreme weather conditions lead to significant changes of the birds’ essential habitats. In many cases these are likely reasons for the decline of bird populations and changes in migration patterns.”
The Black Stork is just one of many bird species and its Sahara route is just one of many used by the variety of species on their seasonal migrations that are coming under assault. As you read the article: Climate Change and Migratory Birds, think about not just the Black Stork and not just about birds, but all global species – humans included.
Birds do not need to engage in any rigorous debate on climate change. They simply take flight and search for points along their long-established migration routes to refresh lost energy en route to distant breeding grounds. The land below speaks loudly to them. Habit forces them to land. It does not take them long to understand what might be the same and what might be different. Then, they must take flight and continue their journey. Or, they must rapidly change their long-established evolutionary patterns to avoid extinction
In the meantime, the human debate about climate change continues in spite of growing signs that things at ground level are beginning to change regardless of who wins the debate.