USA NPN National Phenology Network

Taking the Pulse of Our Planet

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An observer who took this picture in his backyard reported "yes" to flower visitation for a monarch butterfly, and "yes" to open flowers on the milkweed plant.

Image credit:
Howard B. Eskin

Our Scientific Approach

The USA-NPN promotes status monitoring, a standardized approach to observing phenology, which builds on previous methods, has been vetted by a community of researchers and can be adapted to a range of questions, sampling designs and ecosystems.

Status Monitoring

Observers following a status monitoring approach visit a site regularly to check the phenological status of marked individual plants and animal species. Life stages, or phenophases, are reported as a series of yes/no questions.

This approach ensures the capture of negative data (when the phenophase is not occurring), repeat events (for example, a second wave of blooming after a desert rain), and allows for an estimation of the uncertainty around the beginning or end date of a life stage.

Use the USA-NPN protocols independently or as part of Nature’s Notebook

The USA-NPN has developed protocols (suites of phenophases) for 35 plant and animal functional groups found in the United States. These protocols PDF Icon can be downloaded and used independently in the field by any researcher or organization.

In addition, the USA-NPN has implemented the status monitoring approach for the 1000 plant and animal species available in its Nature’s Notebook program. This program consists of online training and species information, as well as interfaces (web and mobile) for data entry, an online database and data access tools.  

Through the efforts of the National Park Service's Northeast Temperate Network, protocols are available for acoustic and camera monitoring of phenology (see full protocol or an R toolkit for phenocam data).