Ducks in Finland and Denmark are hunted for sport, and researchers wanted to see if the number of ducks harvested each year matched how many duck babies were born. They found that the number of goldeneye ducks harvested in Finland went up when more baby ducks were born, which is good for managing their population. However, for teal and wigeon ducks, the number of babies born didn't really affect how many were hunted. This means we need to keep a closer eye on duck populations and hunting to make sure we're not harming them.