Future of Four Seasons in Maine and the Maine Data Literacy Project
When are the hummingbirds likely to arrive this spring?
Background: It’s finally starting to feel like spring outside. The temperatures are
warming, there are patches of grass peeking through the snow, and we’re beginning to
see birds migrating north for the summer. Among those birds is the tiny Ruby-throated
Hummingbird. Weighing in at only 2 to 6 grams, it migrates from southern Mexico,
across the Gulf of Mexico, to its summer home as far north as southern Canada each
spring and back again each fall.
The graph below is line graph showing the number of adult male and female Rubythroated Hummingbirds captured each day by a group in Quebec, Canada in 2007
between May 6th and August 27th. On days where zero birds were caught, either there
were no birds out that day or it was too windy or rainy to catch birds safely.
Number of hummingbirds captured
Number of adult hummingbirds of each sex captured per day, by capture date (2007)
Data Source: http://www.projetcolibris.org/English/projet2007.html
1. Describe what the graph shows about hummingbirds between May and August in
Quebec.
Purpose here is to elicit description of what the graph shows. Sample response: The highest captures
per day occurred between May 14 and June 6, with a peak of 25 birds captured on May 24th. Capture
dropped off to between 1 and 5 per day until July 31st, where it picked up again with a maximum of 12
birds on July 31st. Hummingbird activity dropped off again around August 20 th.
2. I interpret the graph to mean….
(Purpose here is to elicit an explanation (e.g. of the pattern or variability) or interpretation of the
meaning in terms of the context of the question. Sample response: The evidence suggests that
hummingbirds migrated north through this area (in Quebec) between May 14th and June 6th and back
south between July 31st and August 20th. The increased captures between July 31 and August 18 were
probably hummingbirds migrating back south from summer locations farther north. There are a lot
more hummingbirds migrating north through this area in the spring than in the fall. It may be because
the birds take a different route when migrating south or because many adults die over the course of the
summer.)
Extra question for teachers to consider:
How does the timing of spring arrival of males and females compare? What about
the southward migration?
It looks like the males arrive first in spring, but a pair of box or dot plots might be easier to tell for that
question. It looks like both sexes leave in the fall at the same time.