What is phenology?
According to the National Phenology Network, “phenology is the study of the timing and cyclical patterns of events in the natural world, particularly those related to the annual life cycles of plants, animals, and other living things.” You can think of it as “nature’s calendar.”
Examples of annual events include:
- the dates that Lake Mendota freezes in the winter and thaws in the spring
- the date in early spring when male red-winged blackbirds first begin singing to declare their territories near University Bay
Watching the seasonal cycles of its plants, animals, and physical systems is a fascinating way to deepen your appreciation and understanding of a natural area like the Lakeshore Nature Preserve. Everyone can enjoy phenology, no matter how much or how little they know about natural history. Small children can grasp its core concepts, and senior scientists still find wonder in the insights it generates. Phenological observations also help us understand how our climate is changing.
Start looking!
How do you get started observing these natural cycles? One great strategy is to identify a trail you especially enjoy, and walk it every week from March through July. Visiting the same places in the Preserve weekly or monthly will reveal how they change in predictable ways.
Click each season page below to find a list of natural events that are easy and fun to observe. Find your season and your trail—and start looking!
Recording the rhythm
Nature watchers have observed and recorded the timing of events like these—and countless others—from time immemorial. This is reflected in historical records, poetry, and folklore from around the world.
If watched and recorded carefully, the historical record of past seasonal change can be used to predict future events as well. In the seasonal examples we offer below, we’re essentially predicting the future for you: if you want to see Jack-in-the-Pulpits in bloom, for instance, go looking for this plant in early spring.
Many phenological records note the first occurrence each year of a particular biological event, such as the first observed blooming of a particular wildflower. But phenology is not limited to recording just the beginning of an event. It can also include when that event ends: for example, when the nesting period for a particular species of bird is complete.
Phenological record-keeping isn’t limited to biological events. Phenology includes observations of the timing of physical phenomena in a given locale, such as the dates of freezing and thawing for Lake Mendota collected over the past 150 years. These have provided scientifically valuable information showing how a particular lake in the Midwest is responding to climate change.
When these recorded observations of Lake Mendota are combined with similar observations of lakes, streams, and rivers throughout the northern hemisphere, the result is a compelling history of how ecosystems are changing in response to changing climate. In fact, phenological records are providing some of the most convincing evidence for climate change.
Beyond their scientific value, phenological observations are easy and fun. They allow us to observe the pulses and rhythms of places we hold dear. We can also share our observations with people at different locations, and the combined records can then paint a picture of changes in the timing of similar events across different landscapes. Simple though such studies may seem at first glance, they have been quite central to our understanding of climate change.
Learn more!
The following are excellent sources of information if you’d like to deepen your knowledge of this fascinating science of phenology:
Wisconsin Phenological Society
EEK! Environmental Education for Kids
USA National Phenology Network
Aldo Leopold Foundation Phenology: Stan Temple Talks Phenology