the bird's children may be crippled if it gets tangled in their feet while they're still developing, see https://en.wikipedia.org/wiki/Stringfoot https://en.wik

the bird's children may be crippled if it gets tangled in their feet while they're still developing, see https://en.wikipedia.org/wiki/Stringfoot https://en.wikipedia.org/wiki/Stringfoot (which is in general a common sight wherever pigeons can be found); when my flat's fibreoptic was being installed, the cable-layers made a big deal of collecting the cuttings where they spliced the cable and ensuring nothing would be in reach of any animals.