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Sartori L.,University of Padua | Bulgheroni M.,Ab.Acus S.r.l. | Tizzi R.,Oceanomare Delphis Onlus | Castiello U.,University of Padua | Castiello U.,Centro Interdisciplinare Beniamino Segre
Frontiers in Human Neuroscience | Year: 2015

The aim of the present study was to investigate the effect of observing other’s movements on subsequent performance in bottlenose dolphins. The imitative ability of non-human animals has intrigued a number of researchers. So far, however, studies in dolphins have been confined to intentional imitation concerned with the explicit request to imitate other agents. In the absence of instruction to imitate, do dolphins (un)intentionally replicate other’s movement features? To test this, dolphins were filmed while reaching and touching a stimulus before and after observing another dolphin (i.e., model) performing the same action. All videos were reviewed and segmented in order to extract the relevant movements. A marker was inserted post hoc via software on the videos upon the anatomical landmark of interest (i.e., rostrum) and was tracked throughout the time course of the movement sequence. The movement was analyzed using an in-house software developed to perform two-dimensional (2D) post hoc kinematic analysis. The results indicate that dolphins’ kinematics is sensitive to other’s movement features. Movements performed for the “visuomotor priming” condition were characterized by a kinematic pattern similar to that performed by the observed dolphin (i.e., model). Addressing the issue of spontaneous imitation in bottlenose dolphins might allow ascertaining whether the potential or impulse to produce an imitative action is generated, not just when they intend to imitate, but whenever they watch another conspecific’s behavior. In closing, this will clarify whether motor representational capacity is a by-product of factors specific to humans or whether more general characteristics such as processes of associative learning prompted by high level of encephalization could help to explain the evolution of this ability. © 2015 Sartori, Bulgheroni, Tizzi and Castiello.

Visser I.N.,Orca Research Trust | Zaeschmar J.,P.O. Box 91 | Halliday J.,6 Kennedy Street | Abraham A.,Care of Orca Research Trust | And 13 more authors.
Aquatic Mammals | Year: 2010

The first record of killer whale (Orcinus orca) pre-dation on false killer whales (Pseudorca crassi-dens) is reported here. On 25 March 2010, a group of 50 to 60 false killer whales, including approximately 15 calves and accompanied by three to five bottlenose dolphins (Tursiops sp.), were sighted in the Bay of Islands, New Zealand. Within 30 min, they were approached by a group of approximately eight killer whales. Five false killer whales were attacked, with at least three rammed from below, forcing them out of the water. After 29 min, the killer whales were milling at the surface and feeding on the carcass of a false killer whale calf, possibly the only individual killed. The killer whales had prolific fresh and healed oval wounds, which were attributed to cookie cutter shark (Isistius sp.) bites.

Pulcini M.,European Commission - Joint Research Center Ispra | Pulcini M.,Cts Inc. | Pace D.S.,Oceanomare Delphis Onlus | La Manna G.,Cts Inc. | And 3 more authors.
Journal of the Marine Biological Association of the United Kingdom | Year: 2014

This paper represents the first quantitative assessment of the distribution and abundance of bottlenose dolphins (Tursiops truncatus) inhabiting the waters around Lampedusa Island, Italy. Eleven years of photo-identification data, collected from 1996 to 2006 by three different research groups, were brought together, reviewed and analysed to fulfil the following objectives: (i) to obtain baseline information on the abundance and residency of the local bottlenose dolphin putative population; (ii) to review the current Marine Protected Area (MPA) boundaries, especially those referred to waters around Lampedusa Island, with a view to establish a new Special Area of Conservation (SAC); and (iii) to explore the potential and limits of analysing heterogeneous datasets to improve future data collection methods. The most resident dolphins were regularly observed in six specific areas around Lampedusa Island. From a total of 148 photo-identified bottlenose dolphins, 102 were classified as well-marked. The capture histories and the distribution of sightings clearly show a number of dolphins regularly use the study area. Best estimates for the first period within the 'core study area' were obtained for 1998 data. The 2005 estimate was significantly larger than the 1998 estimates (z = 2.160; P < 0.05) compared to that of 1998. Implications of our results for the current MPA, for transboundary conservation initiative involving Italy, Malta and Tunisia and for directing future research within and outside the MPA are fully discussed. © 2013 Marine Biological Association of the United Kingdom .

Mussi B.,Oceanomare Delphis Onlus | Miragliuolo A.,Oceanomare Delphis Onlus | Zucchini A.,Oceanomare Delphis Onlus | Pace D.S.,Oceanomare Delphis Onlus | Pace D.S.,University of Rome La Sapienza
Aquatic Conservation: Marine and Freshwater Ecosystems | Year: 2014

Boat surveys aimed at studying sperm whales in the Tyrrhenian Sea were conducted between 2002 and 2011. During 768 daily surveys, a total effort of 32602km was achieved within an area of 8800km2 resulting in 92 encounters with 229 sperm whale individuals. Average encounter rates of sperm whales was 0.5 groups per 100km2, with a higher concentration in the vicinity of the submarine canyon of Cuma, confirming the importance for the species of this small hotspot in the Mediterranean Sea. Encounter rates increased with increasing distance from the coast. It is possible that the intense boat traffic and anthropogenic disturbance in the area may be moving animals away from the coast leading to habitat loss. The species-habitat relationship documented in this study has implications for conservation. © 2014 John Wiley & Sons, Ltd.

Pace D.S.,Oceanomare Delphis Onlus | Pace D.S.,University of Rome La Sapienza | Miragliuolo A.,Oceanomare Delphis Onlus | Mariani M.,Oceanomare Delphis Onlus | And 2 more authors.
Aquatic Conservation: Marine and Freshwater Ecosystems | Year: 2014

The sperm whale (Physeter macrocephalus) is one of the eight species of cetaceans routinely encountered in the Mediterranean Sea; however, information on the social organization of sperm whales living in the basin remains scarce. The social behaviour of sperm whales within female units, and groups of males are reported, made over an 11-year period (2002-2012) in waters around the islands of Ischia and Ventotene (Tyrrhenian Sea, Italy), an area characterized by the presence of a submarine canyon system and a coastal marine protected area ('Regno di Nettuno' MPA). Different types of aggregations were identified, consisting of social units and two arrangements of males (bachelor groups and clusters). Close clustering at the surface was recorded both for social units and bachelor groups, with evidence for long-term relationships between females (as expected from other studies) and, surprisingly, also among some immature males. Such long-term associations between individuals in bachelor groups may allow immature males to benefit in several ways, including optimizing feeding efficiency. © 2014 John Wiley & Sons, Ltd.

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