The international team of ornithologists together with their colleagues from the Moscow State University spent several years studying the migration of bar-tailed godwits. They found that the phenology of their migrations has changed due to the impact of global climate change in the Arctic. In turn, these changes were catastrophic for the birds, leading to a reduction in the number of their populations.
Birds that migrate each year cover considerable distances in order to perpetuate the species in northern latitudes and wintering in warm regions. For example, bar-tailed godwits are a species of birds of the sandpiper family. They are located in West Africa throughout the unfavorable cold period, and in the spring they move to the Arctic for reproduction purposes.
They make a one midway stop on the coast of the Wadden Sea, which is in Western Europe. They stay there for about 25 days. During this time, they manage to regain strength and increase their body weight by almost 2 times, which allows them to overcome a long distance to their destination without landing.
The lack of rest does not allow birds to recover, which has a very negative impact on their rate of survival. Speaking of numbers, the journey from the Wadden Sea to the north proved to be intolerable for 2% of the birds. At the same time, such a negative effect is more pronounced in females, who spend much more energy on the flight. Studies have shown that between 2002 and 2016, the population of this bird species has diminished almost by 50%.