Arthur G. Butler — Colour-change in Birds



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yellow to a dirty pink or creamy white As instances, our friend

mentions the Linnet, the Red Cardinal, the Orange Weaver, the

Sepoy Finch, the Scarlet Tanager, and one or two Australian birds.


We all know that the Linnet and its allies, among which I certainly

should include the Rose Finches, lose their rose and crimson colouring

at the first moult. The Pine Grosbeak and Crossbills do likewise,

and the American Nonpareil Finch loses its scarlet underparts in

patches, becoming more and more yellow at each successive moult

if kept in* an indoor aviary or flight-cage not exposed to bright

sunlight, and if not supplied with an abundance of living insect-

food. If, however, it is removed to a sunny outdoor aviary and given

additional natural food, the red colouring is gradually restored at

each successive moult (I still have three skins of specimens formerly

living in my aviaries which indicate these facts).


Touching the Virginian Cardinal, the Orange Weaver, and the

Scarlet Tanager, my experience differs wholly from that of our

Australian friend. I have had three cock Virginian Cardinals, two of

which I have kept in large cages and the third in an outdoor aviary,

and they all retained their bright colouring to the end of their lives ;

so also did my two male Scarlet Tanagers, which lived in a bight-

cage for over eighteen years. As regards Orange Weavers, I have

remarked more than once that their colouring tends to deepen

with age. I have never known them to become paler, and I have

kept many examples ; indeed, among the twelve skins of the species

which I have preserved I have bve males in breeding plumage,

not one of which shows any deterioration in colour. The same is

true with regard to the Grey Cardinals, the Military Starlings, and

many other birds; they retain their colouring perfectly. It is true

that a pair of Pintailed Nonpareils in my possession became melanistic

after their second moult, and the abdomen of the male changed from

scarlet to yellow; but I have seen similar examples in the British

Museum series, which apparently were obtained from collectors,

so that neither captivity, lack of sunlight, nor sufficient live insect-

food could have caused the change in them.


I do not think our friend should assume, because <£ colour is

produced by interference of light waves ”, that feathers contain no



