March in the Midwest and East US was very warm, usually
so. Chicago experienced 8 days over 80 degrees, when there is usually only one
day over 80 degrees in April. Unofficial reports suggested that spring flowers
and leaf flush come to Chicago 5-6 weeks ahead of normal. April turned cooler
but peonies in Indiana and Michigan are still blooming two weeks before
Memorial Day. The peony is a patron flower of Memorial Day here in
the Midwest. As the climate changes further, we might need to find a new flower
for honoring the graves of loved ones on Memorial Day.
So who is keeping track and making sense of this stuff—these
anomalies in climate and the timing of creatures? The answer is the National Phenology Network (NPN), a government-funded organization that is
collating and investigating one of the most visible aspects of climate and
climate change. “Phenology” means
“ecological timing” in the parlance of ecologists. The NPN sits in Tucson, AZ but
interfaces with scientists, managers, and the public nationwide. Anyone can
submit observations to the NPN to help in their research. You could post an observation about the first arrival of a
migratory bird in your neighborhood or the timing of lilac flowering in your yard. Postings are made via their public database at Nature’s Notebook. You can also visualize
data that others have contributed to the database at http://www.usanpn.org/.
Several studies have shown that climate change is altering
the timing of life (see this paper or this one).
Spring has come earlier to many parts of the country and world, leading in some
cases to mismatches of species (e.g., see this study).
Experiments also show that warming can change the timing of two or more
interacting species, changing them in ways that affects their overlap and
individual success. Take the endangered species, the Bay checkerspot butterfly,
for example. When we warmed the Bay checkerspot and its habitat, we found that warmer conditions accelerate the insect and it’s food plants. But that
acceleration happened faster in one host plant species than another, increasing
the butterfly’s reliance on the second host species, when and where it
is available. This result means that warming affects the butterfly itself but also affects its success by changing the timing of its food.
Recording observations about the timing of life is one of the easiest ways to
track the effects of climate change. Such observations are a kind of
“biometer” (like “thermometer” but measures how creatures perceive the
climate). There are several things that researchers need to learn about
phenology to maximize the value of its measurement, however. First, we need to learn
if shifts that we see in species’ timing are useful changes that represent
adaptive (good) adjustments that species are making, or if those changes are
maladaptive adjustments that undermine a species’ or ecosystem’s success. We
also need to better understand *why* species are changing at all: What cues are
they reacting to? What genes or traits control these responses? And why do some
species or populations adjust and others do not? Finally, we need to determine
how much of the changes in species and ecosystem timing are due to exposure and how much is due to
sensitivity. In other words, are species and populations changing because the climate where they live is shifting rapidly, or are they instead finely tuned to climatic variables?
We can look in the future to the NPN for answers to these and
other questions. Please help the NPN by contributing your own observations. (Anybody can
do this!) And keep an eye on the NPN as they grow and discover new things about our
changing world.
Also, check out efforts related to the NPN at the Chicago
Botanic Garden, called Project Budburst.