Four Pacific Black Ducks were in the grassy area between the eating shelters and the river. These were possibly two pairs. The pairs had a different response to my presence. Two of them, who were very near the eating shelter located on top of an embankment, started to move down the embankment further away from me as I approached. The other two were already moving up the embankment, and despite my presence, they kept coming. One of them circled around me but beyond that was not too concerned by my presence. It was not even bothered when I crouched down to get a more eye-level photograph.