Ask A Scientist Zoology Archive

name Taylor B.
status student
age 13

Question - I am doing a science experiment in which I a setting out
3 different colored bird feeders (blue, yellow, and green) and seeing
which one attracts more birds and which one has less birdseed left in
it. I also have to do research for this project. I just want to know if
birds, such as the sparrows, pigeons, and doves that will be feeding in
my backyard, are colorblind and how so? Also, how do birds react to
color. If you could, please give me these answers in detail so I can use
some of it to write my research paper.  
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Taylor, 
 
I cannot answer your question directly.
My reason for writing is to give some information to consider when setting up your experiment.
 
There may be other considerations which could lead to a preference of one feeder over the other.  
Your experiment would do best to set up feeders in several areas to minimize error based on 
preference from other influences.
 
1.  Proximity to a wooded area, or the area of nesting:  if a bird is nesting in a wooded area, when 
they approach the feeders they might select the first one they encounter. They too could feed at a 
feeder they feel is most "safe".  "Safe" could mean anything from being safe from predators, being 
farthest from human disturbance, roads, traffic, etc.  Setting several locations with each color 
could show if there is a trend which tries to remove location as an influence.
 
2.  Feed type:  be sure to use the exact proportions of feed for each of the feeders so that a 
change in weight of feed remaining, demonstrating what was consumed,  is not influenced by some 
preference of one seed over another.  This could be a major source of error if not standardized.
 
3.  Size of feeder: these should all be identical, as larger birds might not visit feeders which are 
too small;  if they fed more heavily on a larger feeder, the results of your experiment would be 
skewed.
 
4.  Try to standardize the location.  Feeders in a sunny area might be preferred by some birds, and 
feeding there could be heavier than in shady areas, or vice versa.
 
Bottom line is that I would suggest several locations for the feeders using each color in the several 
locations.  The desire is to isolate, as well as possible from any other influences, the factor you 
are trying to evaluate.
 
Good luck with your investigation, thanks for using NEWTON!
 
Ric Rupnik
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A good way to find information on these types of questions is to search
the medical literature at the National Library of Medicine.  You can use
http://www4.ncbi.nlm.nih.gov/pubmed/boolean.html and type in key words.

A helpful article for your topic, that you can access on the internet,
is in the Journal of Experimental Biology, http://jeb.biologists.org. 
If go to this site and click on search and then you type in bird, color
perception in the key word slot, you'll get the a number of articles,
including: D Osorio, M Vorobyev, and CD Jones, Colour vision of domestic
chicks
J. Exp. Biol. 1999 202: 2951-2959.

Good luck with your experiment and learning about birds and their color
perception.

Laura Hungerford, DVM, MPH, PhD
University of Maryland
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