...The European Breeding Bird Atlas (Ebba2) provides the most detailed picture yet of the distribution of the continent’s birds after 120,000 volunteers and fieldworkers surveyed 11m square kilometres, from the Azores in the west to the Russian Urals in the east.
Overall, 35% of birds increased their breeding range, 25% contracted their breeding range and the rest did not show any change, or the trend is unknown. Forest birds and those protected by international legislation have generally expanded their range, while farmland birds occupy a smaller total area.
Generally, if a species is present in more areas it is less likely to go extinct, but it could be spreading out because of habitat deterioration, and not because the population has increased.
... the situation is really very complex, and that’s why we will provide this dataset for further exploration and investigation,” said Dr Petr Voříšek from the Czech Society for Ornithology."
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“Generally, if a species is present in more areas it is less likely to go extinct….”