University of Arizona
4 files

Plant and Animal Phenophase Definitions

Version 5 2023-04-28, 21:15
Version 4 2023-03-30, 15:16
Version 3 2022-10-12, 18:03
Version 2 2022-10-11, 21:44
Version 1 2022-09-27, 20:46
posted on 2023-04-28, 21:15 authored by USA National Phenology Network

The USA National Phenology Network’s (USA-NPN) standardized phenology monitoring protocols were designed to capture the seasonal life cycle stages of plants and animals across polar, temperate, tropical, and water-limited ecosystems. The protocols can be tailored to any sampling density or frequency and can be used either within the Nature’s Notebook observation program, or independently. The resulting data can be used to answer a variety of scientific and management questions from local to continental scales. 

The protocols are specific to major taxonomic groups and consist of a suite of “phenophases”. A phenophase is an observable stage or phase in the annual life cycle of a plant or animal that can be defined by a start and end point. For plants, phenophases identify the presence or absence of structures (e.g., leaves, flowers, fruits) on an individual plant that is observed repeatedly over the course of one or more growing seasons. For animals, phenophases identify the presence or absence of behaviors such as breeding, migration, and use of food resources. 

Intensity or abundance measures for each phenophase indicate the degree to which the phenophase is expressed. They represent either an estimate of the number of plant structures or individual animals that are present or engaged in a behavior, or an estimate of the percentage of plant structures observed in a particular state (e.g., percent of flowers that are open). 

In this Plant and Animal Phenophase Definitions document, the phenophases in use for major plant and animal taxonomic groups are summarized in tables, and the full phenophase definitions and associated intensity or abundance measures are included in subsequent sections. The multiple files represent updates over time to reduce confusion in the phenophase definitions, include new taxonomic groups, and expand protocols to more fully capture certain life cycle stages. Be sure to use the most current version of the file. Also note the version number for this record does not necessarily correspond to the version number of the most recent Definitions file.

For inquiries regarding the contents of this dataset, please contact the Corresponding Author listed in the README.txt file. Administrative inquiries (e.g., removal requests, trouble downloading, etc.) can be directed to