214 N. Nicholson—Trials of an A viculturist



in advance of the wild Robins and due to hatch within two days.

However, I decided to act immediately and transfer the eggs.


A Hedge Accentor’s nest was discovered in the same area also,

and I decided, for experimental purposes, to place one egg in this nest

and place the other four in the Robin’s nest. The eggs being duly

transferred my hopes ran high once again.


After watching both the Robin and Accentor go back on to the

nest I came back home.


The next day I drove out to make an inspection, and imagine my

feelings once again, on approaching the Robin’s nest, to find all the

eggs of my Bluebird broken and outside of the nest. The beak marks—

of the Robin I have no doubt—could be seen quite clearly on one egg.


My thoughts were now centred on the Hedge Accentor as the only

hope of rearing at least one Bluebird for the season 1932. Upon

approaching the nest the bird flew off and, on inspection, I was amazed

to find her own three eggs in the nest but that of the Bluebird had

vanished. I was not long in finding the egg, it being in the bottom

of the hedge, broken, immediately under the nest.


On arriving home I decided to separate the Bluebirds for this

year at least, and hope for better things next season if they still remain

in my possession.


The questions arising from my experiences are as follow


Had the wild Robins in the two latter cases colour sense, and did

they know that the blue eggs of the Bluebird were not their own ?


In the case of the Hedge Accentor the egg resembles very much

in colour that of the Bluebird but varies a little in size. Did the Hedge

Accentor know the difference in size ?


In the last instance also, was it possible that the wild Robin (she

having only been incubating for three days as against twelve days

by the Bluebird) had the instinct of knowing, from the movement

of the young Bluebirds within the shell, that her eggs could not be so

far advanced ?


In the small area where the Robin’s nests were located to my own

knowledge there have been at least twelve broods of young reared to

maturity, which I think rules out the question of vermin destroying

the eggs. The particular place is miles away from even a village







