Around this time last year I found both engine cowlings in our Seneca filled with birds nests, one of which contained several freshly hatched inhabitants. Nothing visible at all from outside even when looking up through the cowl flaps or through the oil flap, was only because it hadn't run for a while and I'd seen a couple of birds darting around the outside of the cowlings I bothered to take them off to check. It's easy enough to cut a couple of bungs out of foam too, worth the effort.
Last edited by NZFlyingKiwi; 6th Sep 2022 at 07:16.