High-quality data on species distribution and knowledge of species ecology are necessary pre-requisites for their effective conservation. In the European Union, a network of protected areas called the "Natura 2000 network" was set up to conserve the most valuable and threatened species.
The Natura 2000 network was supposed to improve rare species conservation, but has it? In this paper, an analysis of data collected from 1 x 1 km grids on the distribution of orchids in East Macedonia (NE Greece) in two consecutive periods of time (before and after 2010), revealed the degree to which a larger data set (including both periods instead of only one) improved our knowledge of the distributions of species and whether the Natura 2000 network can be used as a basis for the conservation of the orchid flora in this area. When the data for the first period and cumulative data for both periods were compared, orchid species richness and density were very similar.
However, comparison of the two datasets showed that more orchid taxa were recorded per grid in the first than the second period. However, based on the surveys in the second period, the knowledge on orchid distribution increased significantly.
In particular, ten orchid taxa were recorded for the first time in East Macedonia during the second period and significantly more (54.79 % of the total number of species) were recorded. This resulted in a better understanding of their altitudinal requirements.
It also confirmed that most of the orchid-rich grid cells in East Macedonia overlap with the Natura 2000 network, which highlights importance of Natura 2000 for orchid conservation.