Table 1.

Key attributes of effective indicators of biodiversity.

attribute	details
representative	includes all species in a chosen taxon, or a representative group.
immediate	capable of regular update, ideally, at least on an annual basis.
simplifying information	transparent, easy to interpret and visually attractive. Complex information must be presented simply to have impact and communicate.
easily understood	non-experts, from policy makers to members of the public, must be able to grasp the issues to have any ownership of them.
quantitative	accurate measurement with assessment of error. Shows trends over time, measures a rate of change and changes in the rate.
responsive to change	sensitive to environmental change over relatively short time-scales.
timeliness	allows rapid identification of trends—an early warning of issues.
susceptible to analysis	data can be disaggregated to help understand the underlying patterns and shed light on the potential causes of trends.
realistic to collect	quantitative data are available or can be collected readily. Does not require excessive or unrealistic financial resources.
indicative	representing more general components or attributes of biodiversity than just the constituent species trends, ideally reflecting ecosystem health.
user driven	developed in response to the need of stakeholders.
policy relevant	indicators aim to provide signals to policy customers to help them develop and then review policy measures.
stability	buffered from irregular, large natural fluctuations.
tractable	susceptible to human influence and change.