CorMedNet – a baseline database of the distribution and demographics of Mediterranean coralligenous species

Knowledge of habitat and species’ distributions and their conservation status is crucial to enhance their conservation and management plans, which is especially urgent in the current era of rapid environmental change driven by anthropogenic activities. Scientists have been collecting data for several decades on the coralligenous assemblages in the Mediterranean Sea, one of the most important habitats with high levels of associated biodiversity. However, the inconsistency, lack of harmonisation, and dispersion of data across different sources limit their applicability in sound, broad-scale strategies. Here, we present the CorMedNet database, a collaborative and open-access initiative designed to boost the acquisition of baseline information on the distribution, demography, and population genetics data of Mediterranean coralligenous assemblages. Through a literature review, the CorMedNet database compiled 8575 georeferenced records representing local populations of 418 macroinvertebrate species. Although currently limited to cnidarians, poriferans, and bryozoans, CorMedNet is designed to encompass the full diversity of coralligenous species, including other relevant taxa such as calcareous algae. This version represents the most comprehensive dataset available to date for macroinvertebrate species inhabiting coralligenous habitats. The analysis of the compiled data showed that records were mainly from a limited number (14) of species which are considered habitat-forming species. Moreover, information is geographically biased towards the NW Mediterranean and mainly related to species distribution. Demographic and population genetic studies represent only 26.7% of records. In addition, there is a lack of long-term demographic studies, hindering our ability to examine the conservation status of populations at relevant temporal scales. For that reason, the ultimate goal of the CorMednet initiative is to provide a common platform to foster continuous data integration while identifying the main gaps in knowledge. We therefore expect that CorMedNet will also become a key resource to guide research actions and support the design and implementation of effective conservation and management strategies for the unique Mediterranean coralligenous.