Kestrel and Grey Wagtail nests have been raided by egg thieves in Sculthorpe.
Police are appealing for more information after the eggs were stolen two nests in Sculthorpe Meadow between May 4 and Thursday, June 4.
Officers believe this incident is linked with the theft of Marsh Harrier eggs last month in Guist.
Kestrels and Grey Wagtails are protected under the Wildlife and Countryside Act 1981 and officers would like to hear from anyone who believes they may have seen any suspicious behaviour in the area.
Anyone with information about egg thefts should call the 101 number.