Hi, thanks for replying to this post! I originally had a longer version of this, but I accidentally clicked on “cancel” instead of “reply” because I’m still getting used to this interface.

I understand where you’re coming from. I’m in no way familiar with bird biodiversity, specifically in Germany where I live, but I’ll try and present (what I think is) a argument against this:

We can’t successfully keep the cats out of the garden long-term. We can do it for a few days, but then a neighbour lets them out or they lift up the catflap backwards or something else frees them. It’s, unfortunately, a pointless venture.

There’s also the issue of shrinking living options for the birds in our city’s center (“Altstadt”). Homeowners have started putting up nets and barriers in places where birds have been coming for literal centuries, and because of that, they’re becoming increasingly desperate and come to our garden.

We’ve decided to leave this the way it is for now because

1. Most of the birds still make it. About 80% of the birds that don’t fall out of the nest make it. Even the ones that do have a good chance.
2. Helmut’s bird amount has remained about the same for the past decade. It’s always 1-2 birds a year.
3. The birds simply have no other place to go. We don’t let the cats out, they find a way out. We don’t let the birds in, 2-4 nests don’t get built.

I understand if you don’t agree. But we’ve simply done what we see best, and you are completely in the right to disagree.