Abstract
This report provides an evaluation of cetacean indicators (current and potential) with respect to a pre-defined list of activities and pressures, and also ecosystem structure and function. A summary of national and international policy and legal commitments for monitoring and surveillance is also provided.
There is only a single indicator currently in operation associated with a particular pressure: bycatch. Bycatch is the single most important anthropogenic impact on cetaceans in general and, in particular, small cetaceans. Additionally, a single ecosystem structure and function indicator is also in current operation: bottlenose dolphin abundance and area usage in relation to Special Areas of Conservation.
Because so few pressure related indicators exist for cetaceans, this review also includes consideration of potential indicators for which a body of work already exists. These are predominantly focused on synthetic and non-synthetic pollutants (e.g. metals, organotins, PCBs, brominated flame retardants and radioactivity), but also cover elements of underwater noise, climate change and additional ecosystem structure and function indicators. It should be noted that these potential indicators are speculative and would require validation prior to their implementation.
The sample requirements for this variety of indicators can readily be met by current monitoring and surveillance (e.g through the UK Cetacean Strandings Investigation Programme and the UK Bycatch Monitoring Scheme), although, a commitment to undertake additional analytical work will be required. The most significant gap the UK has in implementing its policy obligations is a systematic surveillance and monitoring scheme. Such a strategy is currently under development by JNCC in line with the UK Marine Monitoring and Assessment Strategy (UKMMAS).
With cetaceans it is often difficult to link cause and effect, and to distinguish natural from human impacts on the species. The implementation and refinement of a strategic monitoring and surveillance programme will be essential to meet the requirements of the EC Habitats Directive and the MSFD. This will need to advocate a coordinated transboundary approach due to the wide ranging and highly mobile nature of cetaceans. A better understanding of the abundance and distribution patterns of cetaceans, including any existing persistent seasonal variations, as well as basic life history parameters for most species (growth rates, age at sexual maturity, reproductive rates and mortality) would help determine the magnitude of any impacts to populations and also potentially aid industry in reducing the risk of impacts.
Accompanying the report are a series of Excel spreadsheets:
- Documentation of indicators of pressures (Annex 1).
- Documentation of indicators of ecosystem structure and function (Annex 2).
- Identification of an effective indicator set (Annex 3).
