Deaf birds


Each time I attend a motor racing Grand Prix I wonder at the persistence of the local birds in living normally while surrounded by horrendous noise and chaos.

The French Grand Prix was no exception. Welcome swallows challenged the conditions while feeding and rearing their young in a nest in the garage of the McLaren team. I watched all weekend as the parents dived among the drivers, mechanics and press photographers.

At the end of this pandemonium McLaren won and the babies survived. However, the young developed much louder calls than I have heard swallows make before – they are probably partially deaf by now. Still, birds can re-gain their hearing, unlike any other species.

Loud noise and excess mechanical vibration damages and even kills the essential hair cells, leading to a permanent hearing loss. If you look at a chick’s inner ear following such a damaging noise exposure, there are no projections on the hair cells. Some of the hair cells die and are ejected from this cell layer. If you expose a bird to a loud noise that causes hearing loss and kills these auditory hair cells, these hair cells can regenerate and birds can hear again. Valuable work is being done to find out how this regeneration can be replicated in humans.