Global Species Programe: how WWF classifies species

What is a flagship species?

• A flagship species is a species selected to act as an ambassador, icon or symbol for a defined habitat, issue, campaign or environmental cause.
• By focusing on, and achieving conservation of that species, the status of many other species which share its habitat – or are vulnerable to the same threats - may also be improved.
• Flagship species are usually relatively large, and considered to be 'charismatic' in western cultures.
• Flagship species may or may not be keystone species and may or may not be good indicators of biological process.

What is a priority species?

• The terms “flagship” and “keystone” have generally consistent definitions across the conservation community, however “priority species” is a WWF term, and is solely for the purposes of planning and simple communication.
• For WWF, a “priority species” may be either a flagship or a keystone species and is chosen to represent an ecoregion or region.
• A “priority species” is reflective of a key threat across that ecoregion - such that conservation of the species will contribute significantly to a broader threat mitigation outcome. It is often crucial to the economic and/or spiritual wellbeing of peoples within that ecoregion.

What is a keystone species?

• A keystone species is a species that plays an essential role in the structure, functioning or productivity of a habitat or ecosystem at a defined level (habitat, soil, seed dispersal, etc).
• Disappearance of such species may lead to significant ecosystem change or dysfunction which may have knock on effects on a broader scale. Examples include the elephant's role in maintaining habitat structure, and bats and insects in pollination.
• By focussing on keystone species, conservation actions for that species may help to preserve the structure and function of a wide range of habitats which are linked with that species during its life cycle.

What is an indicator species?

• An indicator species is a species or group of species chosen as an indicator of, or proxy for, the state of an ecosystem or of a certain process within that ecosystem.
• Examples include crayfish as indicators of freshwater quality; corals as indicators of marine processes such as siltation, seawater rise and sea temperature fluctuation; peregrine falcons as an indicator of pesticide loads; or native plants as indicators for the presence and impact of alien species.