The Molt Migration
By PJ Maguire
One thing that waterfowl hunters can always learn more about is the migration patterns of ducks and geese. To be successful as a waterfowl hunter it is important to understand how and why ducks and geese use certain migration patterns. Of course weather, moon phases and the calendar all play a major role in waterfowl migration timing, while feeding and resting opportunities dictate the flyway patterns.
Since the inception of the Conservation Order on Lesser Snow geese I have paid more attention to spring migration patterns. The spring migration is something that has been long over-looked and misunderstood by waterfowl hunters.
For instance, the majority of snow geese fly down the Western side of the Central flyway in the fall, while in the spring they tend to fly up the Eastern side of the Central flyway. I could get into detail about this particular phenomenon, but I would like to discuss a different aspect of spring migration, the molt migration.
Every summer ducks and geese loose their primary flight feathers for a short period of time, and then grow new flight feathers. This processes is called molting. While waterfowl are in molt they cannot fly and are vulnerable to predators. Because of this vulnerability, another type of northern migration takes place in the waterfowl world.
This northern migration, coined the “molt migration”, is to the tundra, where there are fewer predators while the geese molt. This is a migration process that waterfowl biologists are just starting to study and understand.
The two waterfowl species that can be most visibly noted participating in the molt migration through North Dakota are: resident Canada geese and drake mallards. Canada. geese, like most species of geese, do not breed in the first and sometimes second years of life. The older geese return to breeding areas sooner in the spring and quickly seek out nesting areas. The younger Canada geese, the juveniles, begin to form large flocks.
Have you ever seen large flocks of Resident Canada geese migrating northwest across North Dakota in early June? Those flocks are those juvenile geese making their molt migration to the tundra. The geese come from all over the Midwest and will likely return to their place of birth in future years for breeding.
In early September the young Resident Canada geese begin to migrate south to find waste grain in harvested fields. While hunting in the Early Canada goose season I have witnessed many high flocks of migrating Canada geese returning to the States. Sometimes in September the geese can literally appear over night.
The U.S. Fish & Wildlife Service uses band data from Resident Canada geese to prove that the molt migration occurs. In the Early Goose season in North Dakota my buddies and I shot a few banded geese during those September hunts. None of those geese were banded in North Dakota. The most common state was Nebraska followed by Minnesota, Wisconsin and Iowa. Most of the banded geese we shot were less than 2 years old.
Have you ever wondered why one does not see many drake mallards in the summer? I am not talking about seeing drake mallards at city parks but about not seeing drake mallards in the wild. That is because drake mallards, like “juvie” Canada geese, also make a northern migration to the tundra to molt their feathers in the absence of predators. Of course the migration for the drake mallards takes place after their breeding duties have been fulfilled.
I have often heard hardcore waterfowl hunters talk about hunting the late flight of Canadian mallards that seems to be “all drakes”. In my lifetime I have been fortunate enough to experience a few of these late flights of drakes as well. The reason there is such a high ratio of drakes to hens is also because of the molt migration.
I am not sure why the Mallards do not push as far South as the geese early in the fall. I believe it is because they have less competition for waste grain. However, it is easy to prove that drake Mallards have a migration of their own, the molt migration.
Understanding the molt migration may not help you to put more meat in your freezer. However, an overall understanding waterfowl and their habits will. Be a student of the game and you will be successful.