Short-Distance
and Long-Distance Migrants
Comparing Robins and Hummingbirds
Overview
Some birds, such as robins, are called short distance migrants.
They migrate with the seasons, but many remain in the United States in winter.
Meanwhile, ruby-throated hummingbirds are long-distance migrants;
they fly up to 2,000 miles between their wintering sites in Mexico and Central
America and their breeding sites in the U.S. and Canada.
Why do these
species have such different migration patterns? What makes each unique?
Compare these spring migrants as you gather data from Journey North updates
and research. As the migration season unfolds, think about how each species'
needs, adaptations, and migration patterns are intertwined.
Laying
the Groundwork
Introduce
the concept of long- and short-distance migrations to students. Ask, Have
you ever seen a robin in your neighborhood in the winter? When do we usually
see robins in spring? When do we usually see hummingbirds (if at all)?
Which do you think is a short-distance migrant? A long-distance migrant?
Have students explain their thinking.
Exploration
- Hand out
the the Student
Record Sheet for comparing robins and hummingbirds. Have students
complete the migration
map comparison activity* at the top. The second comparison (What
prompts migration?) is already filled in.
- Over the
course of the season, students should try to complete the other comparisons,
drawing on Journey North News Updates for robins
and hummingbirds, FAQs,
and other sources. As they do, assign some of the journaling and discussion
questions listed below, and create some of your own.
(* The Teacher
Tips page provides sample responses to the worksheet.)
Journaling
and Discussion Questions
- How do
the factors that prompt each species to migrate (e.g., food and weather
vs. photoperiod) explain their different migration patterns?
- What are
two ways in which a robin's specific food needs and preferences help
explain its migration patterns?
- What are
two ways in which a hummmingbird's specific food needs and preferences
help explain its migration patterns?
- How else
do you think each species' migration patterns are linked to temperature
and other weather factors?
- Which
birds (robins or rubythroats) do you think have a longer nesting season?
Explain your thinking.
How
Could Global Warming Affect
Short- and Long-Distance Migrants?
Scientists
studying climate change have some interesting theories about this.
They believe that long-distance migrants, such as hummingbirds,
may have a harder time adapting to global warming than birds that
don't travel as far. Why? Long-distance migrants depend on changes
in daylength to trigger their migration. Short-distance migrants
respond more to weather clues, so they can gradually move northward
as weather improves. Scientists believe that these birds can get
a jump on resources and outcompete long-distance migrants that arrive
in a region later.
How
Did Scientists Form Their Theories?
They gathered long-term data on climate and on the return
of migrating birds in different regions. As they reviewed and interpreted
data, they discovered that a pattern exists between temperatures
and the average date of return of different species. In one study,
for instance, researchers discovered that short-distance migrants
returned 13 days earlier during the second half of the 1900s (when
average temperatures were higher), but long-term migrants returned
only 4 days earlier.
What's
Ahead?
Global warming is a "hot" topic. Watch the
media for more news from scientists studying climate change. Also
. . .
- See
Journey North's Climate Connections feature. >>
- Learn
about climate change in the arctic. >>
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