Birds as Indicators of Climate Change

The Mönchsgrasmücke, a seemingly unremarkable bird with its gray-brown feathers, captivates with its melodious singing. Males perform lengthy songs that vary in 'dialects' based on their regions, with notable differences between northern German and Austrian singers. Currently, these garden birds are particularly vocal as their breeding season begins earlier than in the past.

According to avian expert Leander Khil, the Mönchsgrasmücke typically winters in southern regions but is increasingly staying in Austria during winter months. Other garden birds, such as the European Robin, Common Redstart, Willow Warbler, and Song Thrush, are also shifting their migratory patterns due to climate change. These short-distance migrants usually winter in nearby southern areas, typically around the Mediterranean. Warmer temperatures in places like Croatia prompt these birds to return home earlier.

The earlier onset of spring leads to a greater availability of insects, which are vital food sources for birds. Consequently, breeding seasons are beginning sooner and lasting longer, resulting in an increase in the number of young birds observed during unusual times of the year, particularly in urban environments. For instance, some Tawny Owls have been spotted raising chicks in the middle of winter.

Another significant consequence of climate change is the growing number of bird species choosing to winter in regions where they previously would not have done so. This adaptability highlights the role of birds as crucial indicators of climate change.

However, the implications of climate change are not entirely positive for avian populations. Increased temperatures, water scarcity, and extreme weather events like floods pose serious threats to birds. While they can migrate to escape harsh conditions, their nests may be destroyed by flooding, and food sources can become scarce. A severe instance of this was observed last summer when heavy rainfall resulted in a massive die-off of swallows. These birds, which feed on flying insects, were unable to catch their food during the storms, leading to thousands succumbing to starvation and exhaustion.

Adjusting to these unprecedented changes requires resilience, but it also presents challenges for many species. To aid birds in adapting to these shifting conditions, experts recommend creating water sources in gardens during hot summers and opting for native plants that attract insects, such as elderberry hedges instead of non-native varieties.

For those interested in birdwatching, Leander Khil has authored a guide titled 'Birdwatching' published by Kosmos Verlag and offers birdwatching safaris in Seewinkel.