The magic of birds’ eggs
By Phyllis Maiden
It has been illegal to take the eggs of wild birds since the Protection of Birds Act 1954
Birds’ eggs are truly diverse and magical, ranging in size from 16mm (wren) to 41mm (pigeon). They contain the substances which, during incubation, will develop into a tiny fledgling, hatching into the nest to be fed by the adult birds until they are old enough to fly.
To put it simply the egg contains membranes and the white albumen which surrounds the yolk. The albumen will feed the developing embryo with water and protein. Incubation time varies from bird to bird, but when the chick is ready to hatch the albumen will act as a lubricant to help the chick to move about and break the shell to hatch.
The shell of the egg, made of calcium carbonate is semi permeable and will let in oxygen and water. They are patterned in many beautiful ways. This depends on where they are laid. They can be spotty, splodgy, plain or speckled.
Nests in hedges and trees will contain bluish or green eggs for camouflage. Robins’ eggs are often a particularly bright blue. Blackbirds’ eggs are a paler blue.
Nests in holes will usually have pale or white eggs so that they can easily be seen.
Ground nesting birds will often have speckled eggs to camouflage them. Skylark eggs laid on the ground, are brown and splodgy.
I well remember nearly treading on a turnstone nest in Scotland. The eggs were exactly the same colour as the surrounding pebbles.
I often see birds’ egg remains in the village but they are mostly the eggs of pigeons. Their nests are very scant and inadequate and a gust of wind will send the whole lot crashing down. I sometimes wonder why there are so many pigeons in the village!