Dear all, The following research papers are now available at the website of Organisation Cetacea (ORCA). They can be viewed by clicking on the link below and then going to the “Downloads” page on the menu bar: http://www.orcaweb.org.uk/index.html Masters Thesis: Using Oceanographic Features to Predict Areas of High Cetacean Diversity Dylan Walker Abstract Current conservation legislation is focused on prioritising areas of high species diversity.Despite this, most oceanic habitats, particularly offshore, remain poorly studied and have received little protection. This study used oceanographic and physiographic features to predict areas of high cetacean diversity. Strong links have been identified between the distribution of cetaceans, their prey, and a suite of physiographic and oceanographic variables (e.g. Murase et al. 2002, Tynan et al. 2005). Cetacean diversity was therefore predicted using a cumulative environmental scoring system (CES) for the features depth (m), slope (°), chlorophyll-a (mg/m3), and frontal significance (arbitrary value) present within a series of pre-set study squares. The predictive power of the CES was tested using Simpson’s Diversity Index (SDI) scores derived from an extensive combined cetacean database from the eastern North Atlantic. Data for 18 species (approximately a quarter of the world’s cetacean diversity) was provided by Organisation Cetacea (ORCA) and Brittany Ferries Surveys (BFS). Results showed that a significant positive correlation only existed between depth and SDI scores (rs38 = 0.336, p <0.05), and between slope and SDI scores (rs38 = 0.370, p<0.05). Further analysis involving SDI scores for species groups ‘baleen whales’, ‘dolphins’, and ‘beaked whales and sperm whale’ revealed that only the ‘dolphins’ group showed a significant positive correlation with depth (Rs38 = 0.422, p = 0.009) and slope (Rs38 = 0.538, p = 0.001). This study is the first of its kind to use remotely gathered environmental variables to predict cetacean diversity, and in so doing, has highlighted a significant relationship between shelf-break habitats with high slope and depth characteristics and high dolphin diversity. Although a number of limitations exist, this research illustrates the potential value of CES as a tool in conservation management, thereby identifying a need for the further development of this concept. Posters submitted to the European Research on Cetaceans 19. Proc. 19th Ann. Conf. ECS. La Rochelle, France. April 2005. European Cetacean Society: The Distribution of Fin Whales in the Bay of Biscay in relation to Bathymetry and Sea Surface Temperature. Farah Chaudry, Nicola Clark, Neal Reay, Ronan Scullion, & Kelly Macleod Abstract Despite being one of the most abundant species in the North Atlantic, very little is known about the distribution of fin whales (Balaenoptera physalus) in relation to oceanographic parameters, including bathymetry and sea surface temperature (SST). Fin whale distribution peaked in August (58.5% of sightings). Mean SST at sighting locations (July – October) was 20.24°C (n = 470, SD = 1.01°C), with a mean depth of sightings at 3350.0m (n = 470, SD = 1049.2m). There was a significant positive correlation between the number of sightings with increasing depth (250m intervals) (Pearson correlation = 0.520, p = 0.027) and between number of sightings and increasing temperature (0.5 °C intervals) (Pearson correlation = 0.744, p = 0.006). Fin whales in the Bay of Biscay show a preference for deep waters off the continental shelf region. Substantial changes in depth over small areas may encourage upwelling of cold, nutrient rich waters to the surface, enhancing productivity. While there appears to be a significant correlation between fin whale sightings and SST, these increased temperatures may induce the high productivity of prey, rather than having a direct impact on whale abundance or distribution. Although the euphausiid bloom occurs in April, fin whales do not aggregate until July, when euphausiids are large enough to become attractive prey. Future studies should focus on primary productivity in the region, and the effect of food on the migration of fin whales to the Bay in the summer months. Further studies should be carried out with expanded survey effort into the south-western shelf region of the Bay of Biscay. Mapping Cetacean Biodiversity in the Bay of Biscay Dylan Walker, Marde McHenry, Ronan Hickey, Steffania Clemente, Nel Beaumont, & Kelly Macleod. Abstract One aim of current conservation research is to prioritise areas with high species diversity for protection (Purvis and Hector 2000). Diversity indices have rarely been applied to cetaceans due to a lack of survey effort in offshore areas where the majority of species occur. These habitats are, however, known to be threatened by the effects of anthropogenic impacts such as overfishing, fisheries bycatch, and pollution. We utilized the Organisation Cetacea (ORCA) openaccess database incorporating 4500 cetacean sightings over a wide geographical area including shelf, slope and oceanic habitats in order to map and compare cetacean biodiversity by habitat within the Bay of Biscay and English Channel. The study area was divided into quarter ICES squares and divided into three habitats based on depth. The number of species occurring in each box was ascertained and a Biodiversity Index (BI) score was developed that attributed the highest scores to the species occurring in the least number of squares. The lowest BI was found in the shelf habitat (5.20). The values for oceanic and slope habitats were 10.53 and 13.31 respectively. Slope habitat was found to have had a significantly greater BS than shelf habitat (p 0.0001). No significant difference was found between the oceanic habitat and either of the other habitats. The results indicate that oceanic, and particularly slope areas, support a higher diversity of cetaceans than shelf waters. All 20 existing and 30 proposed Marine Protected Areas in the Northeast Atlantic are in shelf waters. However, our results indicate that this habitat is likely to have relatively low cetacean diversity. We therefore recommend that greater emphasis be placed on slope and oceanic regions for marine conservation. For further information please contact Dylan Walker by email at: dylanwalker@homecall.co.uk or visit the ORCA website at: www.orcaweb.org.uk