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- When an ecosystem is healthy,
it can do amazing things.
Support pollinators and store nutrients
and trap carbon.
Our life on Earth as humans completely depends
on the health of these ecosystems.
- We know as ecologists that climate change
is already impacting the Earth's biodiversity.
And this is shifting when species are active,
when plants are flowering,
when insects are emerging.
- These really rapid ecological changes
are threatening the ecosystems of many organisms.
About 30% of North American birds have disappeared
in the last 50 years.
That's almost three billion birds.
Last year, 11 bird species were declared extinct
in the United States.
(door clicking)
Birds are very good indicators of ecosystem health.
In my lab, we are really interested
in the evolution and behavior of birds,
bird coloration, bird color vision, and bird eggs.
One system we're exploring in detail is hummingbirds.
The broad-tailed hummingbirds that we study migrate
to the Colorado Rockies every summer.
And the question we're asking is,
how will climate change impact
these broad-tailed hummingbirds?
- You ready? - Yep.
- North. - Okay, north.
- 38 degrees. - Okay.
We've been using time lapse cameras
to understand the secret lives of hummingbirds.
These cameras take a picture once every second.
This is allowing us to build up a really rich data set
to see how foraging behavior may change through time.
We know that at our field site,
the wildflowers are blooming even earlier
than they did a few decades ago.
And that's happening because the winter snow
is melting faster.
- If plants respond to climate change
by flowering earlier in the year,
but their pollinators,
on which they depend for successful reproduction,
don't also come earlier in the year,
this creates a mismatch.
- [Mary] The wildflowers will miss out on pollination,
and the hummingbirds will lose access
to a very valuable resource.
- Which would ultimately be disastrous
for the species in that habitat.
My lab complements Professor Stoddard's work very nicely
because we're trying to understand,
what are the actual predictors of how plants function
and operate in these ecosystems?
(plastic crinkling)
Our experiments actually involve bringing plant communities
from alpine environments down to warmer climates,
(helicopter humming)
the climates they will experience in the future.
And then we can then examine the response
of these alpine communities to these warmer climates.
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We then take this information
and we use it to inform mathematical models
to project the fates of the plant community
at different timescales going forward.
- To answer these questions about the health of ecosystems,
we need a broad interdisciplinary approach.
The Princeton environment makes it especially easy
to do that.
Birds are the starting point
for our scientific inquiries,
but they push us,
they lead us to these interdisciplinary collaborations.
- Oh there you see. - Okay, there.
- Nice.
- [Mary] So even though we're just looking at one part
of this much larger equation,
appreciating bird behavior and evolution
is going to give us our best chance
at protecting and preserving habitats
and healthy ecosystems for the future.
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