There are about 7,000 eggs in the collection, all acquired before 1954.
It has been illegal to take the eggs of most wild birds since the Protection of Birds Act 1954 and it's illegal to possess or control any wild birds' eggs taken since that time under the Wildlife and Countryside Act 1981. The eggs have not been on display for many years.
The first purchase of eggs took place in 1906 when 5 cases containing 496 eggs were purchased from Mr J Britcliffe for £5-8-0d. After the purchase of the Booth Collection of birds in December 1924, Booth's collection of about 3,000 bird eggs was purchased at a cost of £58 in April 1925.
In 1937 gifts were accepted of over 200 eggs from Mr Ainsworth and approximately 360 eggs from Mr Musgrave Whitham. In the following year, Mr Stanworth gave a collection of 500 British bird eggs. The final addition to the collection was the bequest of John Jackson in 1941 of over 2,400 eggs.
By 1938, the egg collections were not on display and the Exhibition Catalogues stated "The eggs are kept in cabinets in the office and may be seen on application."
The egg collections, like some other parts of the Natural History collection, has not been fully recorded in the Accession Registers, There are index cards but no photographs have been taken and nothing added to the Modes database.