Losing my nerves as half-naked birds go au natural

THE nights have been cold around here.

When I go out in the morning to feed the hens there is frost on the ground and often a skin of ice on their drinking water. The hens stand around waiting for a scoop full of food from the bin and I'm sure if birds could shiver they would be shivering.

This is largely because their feathers are all falling out. Just before the weather began to get cold they started to moult. Feathers are rather miraculous things that perform several functions but in a semi-flightless bird like a domestic hen the principal function is to keep them warm. So it’s a bit paradoxical they should start shedding feathers just when they need them most.

This moulting business must be very annoying for the hens but it’s also annoying for me. After feeding the birds I open the nest boxes. There are lots of discarded feathers but no eggs. Hens tend to stop laying while they’re moulting.

There is, of course, an obvious reason for this apparently unseasonal moult – hens are tropical birds and in their original habitat the problem of a lack of feathers on a frosty morning just never arises.

It used to be thought domestic fowl were all descended from the red jungle fowl and were first domesticated in India. However, research has shown that is not entirely true, although the birds in my hen run still share the same scientific name with the red jungle fowl.

It’s now been shown most domestic breeds share the genes of more than one species of wild jungle fowl. You may sometimes buy one of those yellow-skinned chickens in a butcher or supermarket. They are often advertised as ‘corn fed’ and are supposed to taste better. I always assumed the yellow skin was a result of a different feeding regime, but apparently this isn’t so. The gene for yellow skin is found in the wild grey jungle fowl but not in the red so these birds are carrying a gene from a different wild species.

It also appears jungle fowl were first domesticated in south-east Asia, probably Thailand, possibly Vietnam, and not in India. This happened more than 10,000 years ago, making them one of the earliest forms of livestock. The dog is probably the only domesticated animal with a longer pedigree.

Hens seem to have spread gradually eastwards and westwards from their original home. There is evidence that American hens (mostly in South America) arrived directly from Asia and not via Europe. The westward spread reached India and paused there, which is why there used to be an assumption this was where they originated. They then spread via Persia into south-eastern Europe, arriving in places like Romania, Ukraine and Turkey as early as 5,000 years ago. There is then another inexplicable pause before they spread into western Europe.

They were certainly in ancient Greece in 500 BC but it appears they were not kept by the Neolithic farmers of Ireland. We can’t be sure when the first hen arrived here but an Iron Age date around 2,000 years ago seems likely. Today domestic fowl are the commonest birds on earth with an estimated global population of 25 billion.

Looking at my half-feathered hens suffering in the frost reminded me of one other Irish creature which does things at the wrong time of year. Atlantic grey seals have their pups at this time of year so they are born in a season of winter storms and cold. It’s believed they were originally a species that pupped on ice floes and that they haven’t yet adjusted to the fact the last Ice Age is over.

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