cetaceans at risk by plastic debris: first results from the

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Mediterr. (2015), 22 (1): 248-249. A. ARCANGELI1,2 ... 249. Results - The Civitavecchia-Barcelona transect was repeatedly surveyed from. Sept. 2013 to Sept.
Biol. Mar. Mediterr. (2015), 22 (1): 248-249

A. Arcangeli1,2, M. Azzolin3, I. Campana4,5, A. Castelli6, C. Giacoma3, C. Luperini6, L. Marini4, M. Paraboschi4, G. Pellegrino7, A. Ruvolo4, M. Tringali7, A. Vetrugno4,8, R. Crosti9 ISPRA, Dip. Difesa della Natura, V. Brancati, 60 - 00144 Rome, Italy. 2 Università Roma Tre, V. Marconi, 446 - 00146 Rome, Italy. [email protected] 3 Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy. 4 Accademia del Leviatano, Via Astronomia - 00144 Rome, Italy. 5 CISMAR, University of Tuscia, Borgo Le Saline - 01016 Tarquinia (VT), Italy. 6 Dipartimento di Biologia, University of Pisa, Via Derna, 1 - 56126 Pisa, Italy. 7 Ketos, Via Italia, 58 - 95127 Catania, Italy. 8 Università Politecnica delle Marche, Piazza Roma, 22 - 60121 Ancona, Italy. 9 MATTM, Rome, Italy. 1

CETACEANS AT RISK BY PLASTIC DEBRIS: FIRST RESULTS FROM THE FIXED LINE TRANSECT MEDITERRANEAN MONITORING NETWORK CETACEI E PLASTICA: PRIMI RISULTATI DELLA RETE MEDITERRANEA DI MONITORAGGIO Abstract - Marine plastic debris is one of the main threat affecting cetaceans and other macrofauna. A specific protocol was adapted by the Mediterranean network that monitors cetaceans using ferries as platform of observation allowing a complementary data collection on marine macro-litter. Since 2013, the protocol was applied along 5 fixed transects (2700 km monitored year-round) between Italy, France, Spain, Tunisia and Greece. Plastic was the main component of the marine litter, with highest density in summer (2.53±0.5 items/km 2). Kernel analysis revealed variation in distribution of plastic debris and the overlap with squid-eating species distribution. Key-words: cetacean, plastic debris, Mediterranean Sea.

Introduction - Among cetaceans, toothed species are mostly affected by ingestion of plastic litter that can be confused with potential preys. Despite the legislative framework still few data are available in the Mediterranean basin on marine macro-litter and there is a lack of knowledge on sensitive areas where the potential damage to the biota is greater. Based on methodologies in use by international programs for monitoring of marine debris, a specific protocol was adopted by the FLT Mediterranean network (Arcangeli et al., 2013) allowing a complementary data collection on marine mega-fauna and plastic debris (H03.03 Habitats Directive threats code). Preliminary results along the Civitavecchia-Barcelona transect allowed to detect risky areas due to the overlap of high plastic density and squid-eaters records. Materials and methods - An experienced observer is positioned on one side of the vessel and makes the observation by the naked eye, using binoculars to confirm the sighting of debris bigger than 20-25 cm. Data are recorded on a handheld GPS (effort track and marked points) and on data sheets. At the beginning of the survey the width of the monitored strip is defined a priori (up to a maximum of 100 m) based on the type of platform of observation, height, sea state (≤2 on the Beaufort scale) and visibility, assuming that all litter larger than 20-25 cm is detected. For each sighting, composition, source, buoyancy, dimensions are recorded. Within the strip, sea turtles and other macro-fauna is also recorded. Since 2013, the protocol was applied along 5 transects of the FLT Med Mon Network running between Italy, France, Spain, Tunisia and Greece (Fig. 1).

platform of observation, height, sea state (≤2 on the Beaufort scale) and visibility, assuming that all litter larger than 20-25 cm is detected. For each sighting, composition, source, buoyancy, dimensions are recorded. Within the strip, sea turtles and other macro-fauna is also recorded. Since 2013, the protocol was applied along249 5 Cetaceans at risk by plastic debris transects of the FLT Med Mon Network running between Italy, France, Spain, Tunisia and Greece (Fig. 1). Results - The Civitavecchia-Barcelona transect was repeatedly surveyed from Results - The Civitavecchia-Barcelona transect was repeatedly surveyed from Sept. Sept. to Sept. kmeffort on effort for cetacean monitoring (57 runs) 2013 2013 to Sept. 2014 2014 alongalong 2293222932 km on for cetacean monitoring (57 runs) and and macro-litter monitoring runs) 1). We recorded 34 sightings 35563556 kmkm for for macro-litter monitoring (40 (40 runs) (Fig.(Fig. 1). We recorded 34 sightings of ofsquid-eaters squid-eaters[10[10Ziphius Ziphiuscavirostris cavirostris,Cuvier, Cuvier,1823, 1823,Zc; Zc; 21 21 Physeter Physeter Macrocephalus macrocephalus, Linnaeus, 774 items of litter litter Linnaeus, 1758, 1758, Pm; Pm; 33 Grampus Grampus griseus Griseus (Cuvier, (Cuvier, 1812), 1812), Gg] Gg] and and 774 items of (70% of plastic). The proportion of plastic items was higher in Autumn and Summer (70% of plastic). The proportion of plastic items was higher in Autumn and Summer (>72%), lower in the others (72%), lower in the others (