Valley oak acorns

Phenology is the study of the seasonal timing of biological events such as plant leaf out and flowering, insect emergence and the arrival of migratory birds and other animals. Many factors, including climate change, can affect the timing of these recurring biological events.

Many plants and animals are extremely sensitive to changes in their environment. Observing and recording the timing of phenological events or phenophases, such as leaf budding or flowering for plants or date of first nesting for birds allows scientists to document how various organisms are responding to climate change.

Santa Monica Mountains National Recreation Area currently monitors the phenophases for six different plant species at 40 monitoring sites located along 5 hiking trails within the park. Collection of phenological data will allow scientists to better determine the relationships of plants to their environment as well as detect signs of ecological changes due to climate change.