Nature conservation in Sweden is today strongly linked to nature conservation in the EU and is to a significant part regulated by various directives. The EU Habitat Directive is an important directive and focuses on conservation of biodiversity. This report presents a national study where the primary objective was to assess underwater video as a visual method for monitoring of marine habitats and typical species defined in the EU Habitat Directive. The overall goal is to develop a well-functioning and harmonized environmental monitoring program designated to protect and monitor our coasts and oceans.
The project is conducted within the framework of a joint project between the Swedish Agency for Marine and Water Management, the Swedish Environmental Protection Agency and the Swedish Species Information Centre, and the findings are the basis for the manual Visual underwater methods for monitoring of marine habitats and typical species (Havs- och vattenmyndigheten manus) and contribute to the project Biogeographic monitoring (contract 2574-13). The study was conducted during the summer of 2012 with the main objective to compare and evaluate data collected using four different photographic methods, two video analyzing methods and two still image analyses, among themselves and against data collected using SCUBA diving. Variables tested included taxonomic resolution, the ability to estimate various organisms’ coverage with good precision and the cost efficiency of the different methods. To get a general picture of the Swedish coast, five geographically dispersed areas were selected (from the Gulf of Bothnia in the northern Baltic Sea to the Koster archipelago near the Norwegian border). Within each area investigations were carried out on hard- and soft bottoms and included five replicates per bottom type.
The results show that SCUBA gives a higher taxonomic resolution than photographic methods, while video techniques where the whole film was analysed turned out to be better than image photography methods where a number of still images from the videos were analysed. Interesting from a monitoring perspective is that video analyses from the whole film showed equivalent precision and repeatability as SCUBA. Regarding costs, the findings showed that the photographic methods are clearly advantageous in comparison with SCUBA diving technique. To create a harmonized environmental monitoring instrument and to monitor marine habitats and typical species under the EU Habitat Directive underwater video can be regarded as an interesting and good option, as also other recent studies (e.g. Sundblad et al. 2013a, b, c) have indicated.