Swan

Boyd’s Bible Dictionary:

Swans rare in Palestine

Concise Bible Dictionary:

The Hebrew word is tanshemeth, and is mentioned among the unclean birds. The swan has been seen in Palestine, but it is rare, and, as it feeds on vegetation, it is supposed that some other bird is alluded to. The LXX and the Vulgate have the porphyrio and ibis. The RV has “horned owl” (Lev. 11:1818And the swan, and the pelican, and the gier eagle, (Leviticus 11:18); Deut. 14:1616The little owl, and the great owl, and the swan, (Deuteronomy 14:16)). Probably some water fowl is referred to, and the purple waterhen, of the Rallidae family, is a bird that would necessarily be condemned as unclean because of its feeding upon reptiles as well as birds: it seizes its prey by its long toes and conveys it to its mouth. It frequents the marshes bordering the Mediterranean.
The Purple Swamphen