They certainly see the buffalo. Suddenly it dawns on the bemused Italian. These people do not realize that the buffalo are large creatures which only appear to be small because they are far away. In the tangle of the jungle nothing far away can be seen. The pygmy hunters have no understanding, or experience, that would enable them to correctly interpret the scene in front of them.
Some bugs bite.
Others bug might make a small snack, but they will not feed a village. No wonder the hunters are unexcited by the nearness of the biggest feast they might ever know. Sometimes we are staring right at something and we cannot see what is actually there. Our own experience to date and cultural conditioning cause us to see only what we expect to see. The Pharisees and the Scribes have spent a lifetime learning the flora and fauna of the Mosaic law.