I remember as a kid doing a hell of a lot of climbing and exploring and coming across many birds nests which we used to investigate. I remember once a friends saying that we were not to touch the nest as otherwise the mother wouldn't come back and hatch the eggs leaving them to die, how much truth was there in this?
last year blue tits nested in wooden box on gate used as letter box. put note up for postman to leave alone till birds flown some one took no notice and touched nest mother did not come back so i checked 6 baby blue tits dead all in position of waiting for next feed from mother so it is true