With nature and a camera

Chapter V. Nests, eggs, and young

Abnormal eggs

Although birds' eggs, as a rule, follow pretty closely the common type of their species in regard to coloration and markings, extraordinary departures are sometimes met with, and I believe that such variations are generally due to the indifferent health of their layers. I have once or twice met with common Wrens' eggs without markings of any sort, and some years ago took a clutch of pure white eggs from a House Sparrow's nest. I have also seen a Chaffinch's nest containing five pale greenish-blue unmarked eggs. I found a Blackbird's nest in the spring of 1896 containing four small greenish-grey unspotted eggs, the shells of which were rough and granulated.

Coal tit

Some birds lay their eggs straight off, one every day, and then commence to sit, whilst others, probably influenced by the character of the weather, lay irregularly, missing a day or two as they proceed. I have endeavoured to make a series of systematic observations on this point, but accidents and lack of time to carry them out properly have rendered my figures unworthy of tabulation.

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What puzzles me in regard to some birds is that they build in such cramped situations and lay so many eggs that they cannot possibly cover them all except two deep, and yet those in the bottom layer receive a sufficient amount of heat to incubate them. I have seen Coal Tits' eggs disposed in this way, and the bottom row had each worked themselves such deep indentations in the materials with which the nest was composed as to be half buried. I have also seen a Moor hen's nest with nine eggs in it, some of which were piled upon the others. Of course, it may be said that a sitting bird turns her eggs over daily, but even then one would think that the variable amount of heat generated around them must be detrimental to the embryo chick. In the case of the Coal Tit just mentioned, I very much question whether they were turned over at all, because such an action would have prevented the great amount of embedment of the eggs in the materials of which the bottom of the nest was formed.

Members of the Plover family greatly dislike their eggs to lie any way except with their points to the centre of the nest, and, when a boy, I used to alter the disposition of the eggs of Peewits and Golden Plovers in order to see how quickly they would set them to rights again.

According to my experience, birds are not nearly so particular about their nests and eggs as is popularly supposed. I recollect once examining a Dipper's nest, situated in a horizontal cleft of rock, and containing four eggs, which were centred round a sharp piece of stone projecting right through its bottom. I have also seen a Chaffinch's nest with a piece of blackthorn showing through it, although it was quite finished and contained eggs.

Starlings frequently drop their eggs about in the fields. Pheasants, Partridges, Grouse, Eider Ducks, Wrens, and Tits, there is every reason to believe, occasionally lay their eggs in the nests of other birds of their own species, and, in the case of the first-named two, I have found them mixed together in the same nest.