European Ocean Biodiversity Information System

The Fixed Line Transect Mediterranean monitoring Network (FLT Med Net) is a multidisciplinary monitoring project coordinated by ISPRA since 2007, that uses ferry boats as observation platforms to undertake surveys of marine macro-fauna and main threats (maritime traffic and floating marine litter). The programme involves several partners (EcoOcean Institut, CIMA Research Foundation, University of Pisa, University of Tourin, Gaia Research Institute, Accademia del Leviatano, Capo Carbonara MPA, Ketos, University of Palermo, ATUTAX, University of Barcelona, University of Cadiz, Nereide) that share common protocols for data collection across different routes in the Mediterranean Sea. For cetaceans monitoring, data are collected by 2-3 dedicated observers (MMOs) placed on both sides of command deck of ferries during the entire trip, following standard line transect protocol, and observations are undertaken only in good weather conditions (Beaufort state <4). Within this protocol macro-fauna sightings are also collected and used as presence data, recording distance and angle from the trackline, together with number of animals, presence of juveniles, behavior and response to the ship (escape-approach-indifferent). During the same surveys, systematic data of sea turtles and other macro-fauna are collected using the MEDSEALITTER protocol to monitor floating macro-litter within a fixed strip transect. A dedicated observer checks a fixed strip of up to 50 m at the side of the ferry, where all floating items are identified and classified. The dataset here provided consists of sighting data of loggerhead turtles collected between April 2013 and October 2017, along the ferry route between Italy and Spain, crossing the Western Mediterranean Sea region: Tyrrhenian Sea, Sardinian Sea and Balearic Sea. The transect was surveyed all year round, covering more than 79.700 km over 333 transect lines. 117 georeferenced sightings were recorded during the general effort period and during the systematic monitoring of floating marine litter.