Jacques Weber

Status and Trends

Our limited knowledge of the world’s biodiversity, coupled with the limitations of the current approaches to cataloguing biodiversity, are the main driving forces behind new approaches to species identification. Estimates of the total number of existing eukaryotic species range from the most conservative of 3.6 million to over 100 million, with a figure of 10 million favoured by most analysts as the nearest order of magnitude. To date, some 1.9 million species have been deposited in museums.

The Importance of Marine Biodiversity

The study of marine biodiversity is timely and fundamental for a number of reasons (CBD, Global Biodiversity Outlook 3, 2010). Marine biodiversity plays a key role through ecosystem services (provisioning and regulation, amongst others). They provide economic wealth and resources that range from active ingredients for pharmaceuticals and medicine to products from fisheries and aquaculture, as well as contributing to cultural well-being and supplying relevant “biological models” for both basic and applied research. The role and dynamics of biodiversity are central themes when addressing climate change, earth and universe sciences or sustainable use of natural resources. Thus the issues of application involve policy, regulations and ways to globally manage energy and food security.

The Impacts of Human Activities on Marine Biodiversity

Human impacts have been shown to profoundly modify genetic and species diversity (Palumbi 2001) (Fig. 1.9). The main direct impacts are caused by overexploitation and habitat loss, while indirect effects may result from cascading interactions in the food web (e.g. removing competitors and predators from the system) and the effects of environmental change. Dulvy et al. (Fish Fish 4: 25–64, 2003) reviewing local, regional and global marine extinction, identified “exploitation” and “habitat loss” as being respectively responsible for 55 and 37 % of 133 reported extinctions.

Drivers of Changes in Biodiversity and its Uses

In describing the triggering element of a phenomenon, the terms “drivers” and “driving forces” will be used interchangeably here.

Integrated Scenarios and Policies

A wide range of options is available to society, especially stakeholders and managers, to move towards the goals of sustainable use, conservation, and restoration of marine biodiversity. Management approaches include protected areas to preserve ecosystem state and habitat restoration to maintain ecosystem services. A series of additional tools is being developed to enable decision-makers to (1) take ecosystem value into account in their decisions (e.g. in managing recreational uses and tourism), (2) recognise diffuse ecosystem benefits on a local scale, (3) establish property or access rights for living resources (e.g. ITQs or managed quotas) and (4) disseminate knowledge and raise public awareness about ecological footprints, life-cycle analyses, green- or eco-labelling, etc.