Courtship in the Air: Do athletic hummingbirds produce more offspring?

Methods

Summary

I will record courtship displays from territorial males at a local botanic garden. The garden includes substantial habitat for both males and nesting females. 3D flight trajectories will be digitized using computer software, which will enable the calculation of flight speed, acceleration, and other aspects of flight performance.

I will capture focal males, females, and nestlings to collect feathers to be used for DNA extraction and paternity analyses. Adult hummingbirds can be easily capture by using feeder traps which are virtually harmless to the birds. To collect feathers, nestlings will be gently taken from their nests before fledging, and then placed back when done.

Challenges

The process of DNA extraction, amplification, and sequencing in order to assign paternity will require much lab work and funding. Sequencing costs are part of my budget request, and if funded, will go a long way in accomplishing the goals of this project.

This project will require substantial field work, especially to find nesting females and their offspring to collect feathers for paternity analyses. With the aid of undergraduate field assistants, and other volunteers, to record males and track females to their nests I will overcome these challenges.

Pre Analysis Plan

omputer digitization of video recordings will allow for 3D analysis of flight speeds and accelerations, likely important flight performance variables. Sound recordings of displaying males facilitate accurate quantification of wingbeat frequencies (the rate at which the wings are flapped per second). Both methods will allow me to estimate a male's courtship-flight performance.

A protocol for extracting DNA from feathers has been developed in a collaborating lab at UC Riverside. Using this protocol, and hummingbird DNA primers, I will be able to extract DNA for paternity analyses. Assigning paternity will allow me to test whether courtship-flight performance is related to reproductive success (fitness).