To the Committee of Management of the Zoological Gardens   3 February 1859

[3 February 1859]¹

Report on the Aviary

Out of 59 birds received during the year we lost 13, of these 7 died by disease, 1 female blackbird and 1 male trush were killed by a very pugnaceous cock-blackbird, whilst 2 linnets and 2 Goldfinches escaped during a severe storm which caused by a mighty flood great damage to the aviary. If we take into consideration the sickly state of the birds after a long sea-voyage, the morbidity amongst them cannot be regarded as very great.

The following table shows the increase and decrease of the birds.

	1858. from January to December	January 1859.	increase	decrease
Canaries	14	36 males and females	24 2
Goldfinches	6 one female only	4 one male and one female		2
Chaffinches	2 males	2 males.
Siskins	6 males.	5 males.		1
Linnets	7 one female only	4 2 males and 2 females.		3
Java Sparrows	6	5 probably all males.		1
Nightingales	3	1 male		2
Skylarkes	5 (December)	4 2 males & 2 females		1
Blackbirds	6	4 2 males & 2 females		2
Trushes.	4.	3 2 males and 1 female		1
	59.	68	24	13

The increase of birds through breeding would have been greater, had been means available to subdivide the aviary into different partitions for proper separation of some of the species. Thus several nests of the Canaries were destroyed by the other birds. In the additional wing to the aviary now under contemplation separate chambers will be provided.

But what more yet militated against the propagation of the birds was the disparity of the sexes of most species except Canary birds, as shown by the tabulated statement and even in the instance of the blackbirds, altho' both sexes existed, impregnation did not take place. The only female Linnet laid two eggs which became accidentally destroyed. Of Goldfinches we obtained the first female bird only a few days ago. The one of the female blackbirds made 3 nests and laid 13 eggs, which however proved sterile.

[F. Mueller]³