Conditions for various plant and animal species have improved to some degree in recent years after population decreases of many species between 1950 and 1995.. Since 2000, the number of endangered species of mammals, dragonflies and vascular plants has fallen, and since 2005 a slight reduction can be reported in threat levels for breeding birds and reptiles. Other species groups show very little or no signs of recovery.
Between 1950 and 1995, the number of endangered species rose dramatically. More than one third of all species gained Red List status in this period because they were endangered to some extent. The number of endangered species on the Red List can be regarded as an indicator for the state of the biodiversity in the Netherlands. The higher the number of species on the Red List, the worse the condition of wildlife, and vice versa. Nature policy and land management predominantly focus on groups of species with the broadest public support: mammals, birds, reptiles, amphibians, butterflies, dragonflies and vascular plants. These groups are incorporated in their whole in the Red List Indicator (RLI), i.e. virtually all species in these groups that are native to the Netherlands are included. The RLI represents mainly terrestrial and fresh water species. Apart from a few sea mammals, it includes no marine species.
The RLI is used to monitor progress towards international biodiversity goals. In recent years the Ministry of Economic Affairs has incorporated it in its annual budget account to parliament, as a measure for biodiversity.
Approximately 38 percent of all 1,771 considered species were still at risk in 2016. While the number of endangered species was still increasing between 2000 and 2005, it fell again between 2005 and 2016. Since 2000, vascular plants, mammals and dragonflies have improved considerably. Although the average threat status of breeding birds and reptiles was better in 2016 than in 2005, the number of species of these species groups under threat is still the same (and higher than in 2000). Other species groups show very little or no signs of recovery compared to their 2000 Red List status.
The Red List status per species as documented in the most recent official Red Lists, combined with information on population size and the trend in recent years, yields the Red List status of a species for a specific year. The Red List Indicator represents the net outcome of the year-to-year changes in Red List status of all considered species. Since 2005, the Red List status of many species has deteriorated, but the status of a larger number has improved; 28 “vulnerable” and “sensitive” species have improved and 22 have deteriorated. Nine species that were “seriously threatened” of “threatened” in 2005 have deteriorated further, but 36 species have improved. In effect, the most severely threatened species have improved in status in recent years. In addition, 11 species have re-appeared, whereas 5 have disappeared since 2005.
The population size and distribution criteria to determine Red List status were specifically designed for the Netherlands. Although loosely based on similar criteria, they differ from the IUCN Red List methodology. Therefore, it is difficult to compare national results for the Netherlands with those of other countries. A list of countries with the number of species in each Red List category (of the evaluated species) according to IUCN criteria is available from the IUCN.