Potential Use of Sightings Data for Determining Changes in Range and Abundance
Since publications of the Atlas of cetacean distribution in north-west European waters (Reid et al. 2003), many new data relating to cetacean distribution have been collected. The European Seabirds at Sea and Sea Watch databases have been augmented by data from opportunistic, generic surveys, as well as systematic, geographically targeted ones. The SCANS (Small Cetacean Abundance in the North Sea and adjacent waters) survey was repeated over a more extensive area in 2005 , and survey coverage was further extended by the 2007 CODA (Cetacean Offshore Distribution Abundance) survey. In addition to these, other Europen data sets now exist that were not available for the Atlas and would enhance any future update.
There are several national and international instruments that would be served by an updated Atlas; however, perhaps the most appropriate legal driver is the EC Habitats Directive (HD; EEC 1992). All species of cetacean are included in Annex 4 of the Directive, which places an obligation on all European Union Member States to accord them strict protection. This carries with it the requirement to report on species conservation status every six years. Favourable conservation status (FCS) must be assessed with regard to four parameters: natural range, population size, habitat (extent and condition) and future prospects. While some flexibility is accorded to national experts, EC advice recommends the use of time series data to detect change in FCS, possibly in comparison against favourable reference values.
In 2006 a working group was established to update this cetacean data resource and produce a new atlas. It aims to achieve this through establishment of a Joint Cetacean Protocal (JCP) rather than a static database. The JCP will comprise standards for the integration of cetacean abundance and distribution data collected from European waters using a variety of methods. Data will be shared under a common agreement, ideally through a web-based portal demanding little maintenance, which would, if necessary, restrict access to data not in the public domain. This project has received support from ASCOBANS and a growing number of European governmental and non-governmental organisations. As part of the initial phase of the project, exploratory analyses were commissioned by the UK and Ireland on a subset of data from the southern Irish Sea, which were considered representative of the eventual JCP data resource.
The aim of this pilot study was to determine how disparate data types might be integrated and what power the final data resources may have to detect trends in range and abundance. The results of this work are presented here.
Potential Use of Joint Cetacean Protocol Data for Determining Changes in Species’ Range and Abundance: Exploratory Analysis of Southern Irish Sea Data