The migratory birds cover thousands of kilometres to overwinter in warmer climes
The birds usually stay in Spain from April to September, and ‘Operation Exit’ of the swift occurs once they have raised their young and they are strong enough to make the perilous journey, a trip which can now be tracked thanks to the use of geo-locators.
In 2012, the Spanish Ornithological Society (SEO / BirdLife) implanted these tracking devices for the first time on the birds in order to monitor their flight via satellite, after decades of using the much less reliable ring system on their legs.
One of the first swifts equipped with a geo-locator was a bird called Goyeneche, who flew more than 9,000 kilometres in just two months to reach its wintering area between Uganda and Tanzania in early October. The little bird then moved more than 800 kilometres at the beginning of December to settle in a shrubby savannah close to the island of Zanzibar.
Thanks to the monitoring devices, we now know that swifts exhibit a rare migration pattern, whereby breeding populations from southern Europe migrate to the southernmost wintering areas in Africa while northern populations overwinter in areas further north.
As a rule, swifts begin their return journey to Spain in February, crossing Africa, the Gulf of Guinea and the Sahara desert to reach the Peninsula, a trip that can cover more than 11,000 kilometres.
According to the SEO / BirdLife program, each year migration dates vary slightly depending on a number of factors including the availability of food and weather conditions. In 2021, the swifts were a little later arriving for their summer season in Spain, but it remains to be seen if they will now delay their departure.
Image: SEO / BridLife Facebook
Source: Murcia Today