Spotted a Male Hummingbird this morning!! Noticed that the Male always migrates back first. After doing some reading, the Male shows up early to establish territory and also gives time for more nectar and bugs to become available for the female. She needs to reserve her strength for raising her young.

http://www.learner.org/jnorth/tm/humm/MigrationMalesFirstAns.html

This also applies to other birds such as the Baltimore Oriole