What do birds do to nurture their offspring during spring?

The start of spring, and the miracle of life takes place all around us – often without us being aware. From a chrysalis emerging from the soil as a butterfly, hedgehogs and dormice coming out of hibernation ready to mate, to the sounds of different species of birds singing and protecting their territory. Birds will also be finding food for their mate who is probably sitting incubating the eggs in the nest.

When we used to rear rare breeds of poultry, I was fascinated by incubation, whether it was eggs under a broody hen or in an incubator. The fact that there is everything in an egg to become a chick from the calcium in the shell to the protein, minerals and vitamins in the albumen. As the incubation continues it is noticeable that the shell becomes thinner as the chick absorbs the calcium as it grows.

Domestic poultry and wild birds such as moorhens or mallard ducks have a yolk that is bigger than the garden birds. This is because the chick absorbs two thirds of it into its stomach as it hatches. They can therefore survive for at least two days as they learn to feed themselves although still dependant on their mothers for warmth.

Garden birds as an example, have a small yolk in their egg and it is all used up for the development of the chick. When it hatches it will be very vulnerable as it will not have grown any feathers and will be totally dependant on the parents for food. The incubation period is much shorter as they don’t have to develop so far, and this will only be 11 - 12 days in comparison with 20 – 22 for the moorhen or 28 days for a duckling. With really brightly coloured beaks they gape to attract the adults. It means the chick is the kind of creature that only its mother would love rather than a lovely fluffy one!

The chick is tightly curled with its head underneath its wing. At the blunt end of the egg is an air sac. Eventually the chick fills the shell and pierces the air sac with its tiny egg tooth on the tip of its beak. The chick now changes from living in fluid to breathing air. The neck starts to vibrate so that the chick makes the first hole in the shell. Rotating its body very slowly it continues to pierce the shell until it has gone right around the egg and the top will come off. The chick will climb out of the eggshell and exhausted, it will lay as it dries. Life begins.

The aquatic creatures that emerge as insects, and in turn feed all kinds of wildlife – many of them that we are dependent upon to pollinate our food. We need to value and be fascinated by the world about us.