Acopian Bird Savers are a relatively inconspicuous (visible, but not unsightly) way to prevent bird crashes, guaranteed. They’re a light curtain of strings that wave in the wind, in front of your windows – so birds don’t mistake them for trees or sky.

They have a Build-Your-Own tutorial on their website; if you need a more custom solution or just want the materials done right from the get-go, you can order it from them online.

It’s fairly easy apply decals and UV liquid (remember, only useful for some bird species, not all!) by leaning outside and doing it, but the real fix — Feather Friendly — requires access and time to apply it properly. Feather Friendly is probably the most effective solution out there, and it’s meant to last. It’s easy to apply when you live on the ground floor, but not so easy at higher floors. But higher floors still need effective protection.

That means many apartment dwellers and homeowners who don’t have access to an extension ladder might find it troublesome to prevent birds from crashing into windows. (And because they don’t notice the crashes, they doubt they occur.)

I wrote this to help people who either have casement windows or modern sash-hung windows where you can tip the window inward in order to clean it. You need to be able to access the top of the frame of the window on the outside. Also, this DIY fix is affordable, and as it’s not a permanent alteration to the dwelling, you don’t need your landlord’s permission to use them.