Background
Somewhere out there, a robin "calls" your backyard its home
territory. A robin's territory — the place where
mating and nesting occurs — is usually less than half an acre. Territories
often overlap, perhaps because of the feeding grounds that neighboring
robins share. If you think robins are everywhere, you're probably right!
Read on.
Robin
Squabble Story
One summer a Minnesota woman had a pair of robins nesting in her backyard.
A pair of robins also nested next door on one side of the yard and yet
another nested on the other side of the yard. A fourth pair of robins
nested in the yard behind hers. After a few territorial squabbles, the
robins pretty much kept to their own yards for feeding. But
this woman had the only birdbath on the block, so two of the neighboring
pairs of robins started sneaking into her yard for drinks and baths.
At first, the male and female robins who "owned" that territory
spent a lot of time chasing the intruders away.
But when
the female started incubating her eggs, she stopped chasing off the
other females. The male chased off the other males until the babies
hatched. Then he had to spend so much time searching for food for his
nestlings that he stopped chasing off the other robins — unless
they started exploring beyond the bird bath. As long as the neighbors
flew directly to the birdbath along the shortest possible line from
their territory, he left them alone. But if they veered off that path
for just a few seconds, he charged the birds!
For several weeks, the woman observed where each robin spent the majority
of its time. She noted where each robin could range and be ignored by
the others, and where each was when disputes took place. This information
gave her a clear picture of each robin's territory. She could have drawn
a simple map with each territory outlined.
Activity:
Map A Robin's Territory
Observe your own robins and see if you can map their territories! Here's
how:
- Begin
by drawing a map of a small part of your neighborhood. Mark in the trees,
bushes, houses, fences, and other things that robins might notice. Mark
any robin nests you find.
- Use this
map to study the robins in your neighborhood for a week or two. Give
each robin a letter, number, or symbol. See if you can start to recognize
different individuals and notice where each spends its time.
- Mark a
bird's letter, number or symbol in the right spot on your map every
time you see that bird. Do the robins spend more time in some areas
than others? Can you draw territorial boundaries on your map based on
where the various robins spend their time?
Try
This! Activity/Journaling Question
- Set out
a bird bath or a bowl of water or a lawn sprinkler. How long does it
take for robins to notice it? Does the water attract robins from other
territories? How do the birds work out their "water rights?"
National
Science Education Standards
- Organisms
have basic needs. For example, animals need air, water and food
- An organism's
behavior patterns are related to the nature of that organism's environment.
- Behavior
is one kind of response an organism can make to an internal or environmental
stimulus.
National
Geography Standards
- How to
use maps and other geographic representations, tools, and technologies
to acquire, process, and report information.
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