The link you put up describes "stick" and/or "walking fetch" as part of the FF process. Down at the bottom of the page under the heading STICK FETCH ....
"Then the dog is digging out to beat the stick and seems totally reliable without any ear pinch, you are finished--you have successfully force-fetched your retriever".
In fact the last 3 paragraphs on the page describe a "walking fetch" drill and how to implement it. Clearly the author(s) considers this part of FF.
So are you saying you don't FF this way or you do ??
Sorry again for the confusion on my part.
Regardless, again, had the OP included ducks in the FF process at some point, there would likely have never been a problem to solve.