John Dee, (July 13, 1527 to ca. 1608) Elizabethan magus and philosopher to the Queen, was, we learn in The Life of Dr. John Dee (1527 - 1608) (Charlotte Fell Smith, 1909), [possibly] employed by Queen Elizabeth I as a spy....
[S]ome have gone so far as to‘suppose that all the notes of his pretended conversations with spirits, were, in fact, political intelligence, couched in cyphers. As they contain a kind of jargon meaning nothing itself, they might undoubtedly be used occasionally for such purposes. Dee himself avers in his narrative, that he was taken into the Queen’s service on her accession to the throne.
John Dee notes in his diary (March 1579) about his cat getting a young fledgling sparrow " that had never had but one - the right- wing naturally." In this era of exciting new knowledge, everything was investigated since the doors of scientific orthodoxy had not yet crushed the genuine thirst for knowing. That being said, it sounds to me like Dee's cat caught somebody's pet bird.
Dr. Dee died having been "so poor in the latter part of his life as to be obliged to sell his library piece-meal for subsistence..." This library had once been among the grandest in England.