The European Cetacean Society (ECS) was established in January 1987 and aims to promote and advance the scientific studies and conservation efforts of marine mammals and to gather and disseminate information about cetaceans to members of the Society and the public at large (see www.europeancetaceansociety.eu). The ECS is the primary research group concerned with cetaceans (whales, dolphins and porpoises) in Europe.
The next annual conference of the ECS will be held in Galway, Ireland, between 26-28 March. The Science Programme is now available online with 40 long talks, 30 short talks and 3 keynote speakers. Eight workshops are organised for the weekend 24-25 March. The abstract book is now available to download from the conference website.
My personal contribution to the conference will be the following poster communication:
Pierantonio N., Airoldi S. Use of photogrammetry to estimate sperm whales body length in the Ligurian Sea, NW Mediterranean.
Abstract – The sperm whale (Physetermacrocephalus) has unique body features and its size can be estimated using acoustic and photogrammetric techniques. Measuring animal body size, an important characteristic affecting physiological, ecological and life-history traits of a species, can function as tool for summarising diverse biological information. Here, we present photogrammetric body length estimates of sperm whales from the Ligurian Sea. Visual and acoustic shipboard surveys, performed ad libitum between 2008 and 2011, resulted in 239 animals acoustically detected, tracked and recorded. When possible, simultaneous photo-identification pictures and distance to the animal, obtained through a laser rangefinder (LRF), were collected. The camera/lens and the LRF were previously calibrated to relate the distance and the photograph to the fluke span; body size was estimated through a regression equation, previously described for this species. Out of 87 identified whales it was possible to estimate the body length of 40 (45.9%); their size ranging between 7.94-12.88 metres. Based on the current knowledge of sperm whales occurrence in the area, we assumed all animals to be males; accordingly, their age ranged between 6 and 23 years. These findings support earlier acoustic body measurements from the same area. Animals smaller than 9.45 metres (46.3%) were encountered in loose aggregations, while larger individuals (53.7%) were mostly observed alone, confirming what previously reported in the literature. These data represent the first photogrammetric sperm whales length estimates for the Mediterranean Sea, where the population classifies as “Endangered”. This technique does not preclude animals identification, is fast processing and allows several replicates; furthermore, it is very cost-effective not requiring any special equipment. For these reasons it represents a useful tool to evaluate both individual life-history and population parameters, such as growth rate, community structure, size related distribution, density, and home ranges, essential to address conservation issues and establish management measures.