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It's odd that you can see the borders between Belgium and France for various birds (like the swift and cuckoo), same for the border between Germany and Poland.
by 317070 18d ago
It's odd that you can see the borders between Belgium and France for various birds (like the swift and cuckoo), same for the border between Germany and Poland.
I wonder why that is? There are no topological features defining these borders. Maybe the data is normalised in some way across countries?
- Cthulhu_ 18d agoIf this is based on bird spotters, I'd say the national bird spotting organizations don't report or watch for the same birds.
- ileonichwiesz 18d agoThat’s the more likely hypothesis, but I also wonder if different land management practices could be influencing a map like this. Agriculture in Poland is much more fragmented than in Germany - smaller fields of different crops, often separated by meadows and forests, creating lots of niches for biodiversity. In Western Europe you’re more likely to see giant, mechanised monoculture fields as far as the eye can see, leaving less space for agrarian-landscape wildlife.
- _joel 18d agoThe birds remained part of the schengen zone and have freedom of movement :)
- lioeters 18d agoAlways been a bit jealous of birds for their freedom. It comes at a cost of course, but so does being human.
- dspillett 17d agoDifferences in farming practices and hunting rules between countries can have a surprisingly stark effect on the movement patterns of birds, either directly or by affecting their food sources or predators. https://www.bbc.co.uk/news/blogs-news-from-elsewhere-43244856 https://www.bbc.co.uk/news/blogs-news-from-elsewhere-4324485... is a notable example of this.