Why does it say "Yadati Kol Of Harim"?
Radak: You know only those found in settled places.
What is "Ziz Sadai"?
Rashi: They are Remes ha'Sadeh. They are called Ziz, for Zazim (they move) from place to place.
Radak: "Ziz" encompasses all wild animals. The same applies to "v'Ziz Sadai Yir'enah" (80:14).
Radak citing Vayikra Rabah 22:11: Ziz is a giant bird. When it spreads its wings, it weakens the sun - "hami'Binasecha Ya'ave Netz Yifros Kenafav l'Seiman" (Iyov 39:26). It is called Ziz because it has all kinds of taste, mi'Zeh umi'Zeh.
Malbim (10): It is the smallest living creation. Even it is with Me; everything is under My Hashgachah.
Why does it say "Imadi"?
Rashi: I know all of them.