European Ocean Biodiversity Information System

Monitoring abundance and distribution is essential in any conservation strategy, but is often ignored in many regions, including much of the Mediterranean. It is a priority of the Italian Ministry of the Environment, who funded a series of aerial surveys around Italy, to provide significant baseline information on cetaceans distribution and abundance. The covered areas included the Pelagos Sanctuary, the Central Tyrrhenian, the Corsica and Sardinia Seas, and the Ionian Sea and the Gulf of Taranto. Numbers of animals within the Sanctuary are significantly higher in summer, when human activities and thus potential population level impacts are highest. A crude comparison with data from past shipboard surveys suggests an appreciable decrease in fin whale density in the Pelagos Sanctuary area over the last decade, reiterating the need for a major synoptic basinwide survey, as well as regular monitoring surveys. The low CVs and Cis reconfirm the effectiveness of aerial surveys in estimating abundance of certain cetacean species in suitable areas/circumstances and may provide a model for other areas of the Mediterranean. These surveys provide baseline data to develop efficient long-term systematic monitoring programmes, as required by a number of national and international frameworks. The collected data may also be crucial in assessing whether ship strikes, one of the main causes of death for fin whales in the Mediterranean, are affecting the Mediterranean population. Effort data are from 2009 only. When time and observed counts were not available, "00:00:00" and "1" was filled in, respectively.