Comparing
Spring Reports of Robins Singing
Each
spring observers report when they hear their first robin singing
on territory. A singing robin is a fairly clear
sign that the robin has staked its nesting territory for
the season. We can use maps to compare robins reported singing
from
year
to year.
Carefully
study the maps above.
- What
are the two maps comparing?
|
- How
are the the two maps different?
|
- What
do you notice about the number of dark blue dots (sightings
after April 15)?
|
- List
3 ideas that could explain differences between the
two maps.
|
|
