Reproductive effort and success of wild female mallards: Does male quality matter?

- Mallards mate assortatively by body condition. Only young females mate assortatively by body size.
- Younger females nested earlier and had higher nest survival when mated to males with better plumage scores.
- When paired with larger bodies males, younger females renested faster and brood survival increased among older females.
- There is an additive effect of male quality on female investment and success in free-ranging mallards.