A total of 267 pairs of white stork nested in Slovenia this year, which is the highest number since 1999, when the Bird Watching Association started keeping record. The number of storks has been rising in all Slovenia's regions bar the Prekmurje region in the north-east, which has traditionally been home to stork.

The success of stork nesting depends on the weather, especially the amount of rain and temperatures in mid-May when the chicks are hatched. If it is cold and rainy then, many chicks die. In general, stork thrive in dry and warm climate, so this species benefits from climate changes.

Some storks have even stopped migrating to the south, the association said. A total of 588 chicks left the nests in Slovenia this year.

Stork numbers have been increasing in all regions in the country, while in their traditional homeland, Prekmurje, their numbers are declining.

In the plains on both sides of the Mura river 87 stork couples nested in 1999, but this year there were only 46. This means more than one pair stopped nesting there a year on average.

"If this trend continues, the Mura plain will be without stork in 25 years," said the head of the Bird Watching Association, Damijan Denac.

The main reason for the dropping numbers is a massive degradation of ecosystems in Prekmurje, especially of agricultural land, where monoculture farming is spreading. Meadows have disappeared and there is no food for stork on the big fields treated with pesticides.

"It is very worrying that stork, which is a generalist, is disappearing. This means that a collapse of biodiversity happened in the cultural landscape of Prekmurje, and not just a collapse of the number of species but also a collapse of the biomass of different organisms that are food for stork," Denac said.