by: Erin Schoenfuss

Interesting Facts


Many may think not much research has used Tree Swallows as their test subjects, but an interesting fact is that Tree Swallows are considered the fruit fly or lab mouse of Ornithology.  They are the species of choice when it comes to examining song birds.  Some consider them as the “model species.”  They have brought contributions to learning more about not only the biological aspects of other birds, but they have also helped learn more about bird ecology and behavior. 


Tree Swallows work as great “model species” because they are easy to attract.  All you need to do is build a birdhouse and they will be flocking in before no time.  The one advantage to building birdhouses then is that if you do want to do research you bring the Tree Swallows to you and it is easier to manipulate these conditions.  Another advantage to using Tree Swallows as test subjects is that they will return to the same spot each year so you can watch them for years.  Also, Tree Swallows will not desert their eggs or babies if you touch them or need to handle them for research.  Finally, they make good subjects because most of their life is spent out in the open, so you can examine them easily.


In one specific research project, which has been going on for over 40 years, scientists are documenting the laying date of Tree Swallows in North America.  As climate change is raising the temperature and causing spring to come earlier, so are the Tree Swallows.  In 1995 Tree Swallows were coming 9 days earlier than records showed in 1971.  That is quite a significant change.  Research is determining whether or not the cause for early Tree Swallow migration is directly related to the increase in temperature or if it is the increase in food causing the Tree Swallows to migrate for those reasons.  These earlier springs could then allow a greater chance of survival for the young born allowing a greater increase in the Tree Swallow population.


To learn how to attract your own Tree Swallows click How to Build Your Own Birdhouse.  Click here to return return to the Tree Swallow:Tachycineta bicolor Homepage.