The Physiologus says of the turtledove that she loves her mate and is faithful to him; so much so that if he dies she will never take another mate. The Epiphanius version is essentially the same. The interpretation recommends chastity as well as faithfulness to God.
The turtledove in the van der Borcht copperplate engraving below is sitting in a leafless tree. Though it is not mentioned in the Physiologus text, another attribute the turtledove is said to have is that if her mate dies she will never again perch on anything green.
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The woodcut below (from the Rome, 1577 edition) also shows the mourning turtledove perched in a leafless tree. The trees in the background have leaves, suggesting that the turtledove's perch is a dead tree.
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Properties of the Partridge
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