Biodiversity indicators are measurable features that help assess the health and diversity of ecosystems. They can include species richness, which counts the number of different species in a given area, and population trends, which track changes in the number of individuals within a species over time. These indicators provide valuable information about the state of the environment and the effectiveness of conservation efforts. By monitoring biodiversity indicators, scientists and policymakers can identify areas that are at risk and prioritize conservation actions. Tools like the Red List from the International Union for Conservation of Nature (IUCN) and various ecological surveys are commonly used to gather data on these indicators, helping to ensure the sustainability of our planet's ecosystems.