Case Study: Redhead

The Redhead (Aythya americana) is a duck that stays North America (thus the name for the specific epithet, americana). These birds typically breed in the Prairie Pothole Region, an area that is being severely degradated through agricultural practices  thus putting nesting areas at risk for the Redhead, causing population declines. Although still common, they have had sharp declines in the population size.
An interesting topic about the Redhead is that it parasitizes on it's "similar" looking Canvasback. The interesting thing about this, is the Redhead is smaller than the Canvasback, but yet the Redhead is frequently successful. Redheads perchance parasitize because they may be young and inexperienced or they already have an established nest and just put their eggs in other nests to increase their reproductive success. Also, redheads have more options in nesting than typical ducks (they can either lay eggs or not lay eggs):

1. Not lay eggs
2. Lay just parasitic eggs
3. Lay eggs in their own nest
4. Combine parasitism and laying eggs in their own nest

This can increase their reproductive success since they have more options. Other reasons why the redhead may do this is: weather conditions (poor conditions, less likely to spend energy on a nest), young females put a lot of effort into nesting successful, they lose the ability to survive over winter and also there is a certain weight threshold which may make the females switch strategies. Heavier females frequently occupy nests more than the lighter females.  They do not only parasitize on the Canvasback but will often lay eggs in the nests of Northern Pintails, Cinnamon Teal, Mallards and Ruddy Ducks.