Diving apart together Call propagation in diving long-finned pilot whales

Lack of behavioural responses of humpback whales (Megaptera novaeangliae) indicate limited effectiveness of sonar mitigation

Exposure to underwater sound can cause permanent hearing loss and other physiological effects in marine animals. To reduce this risk, naval sonars are sometimes gradually increased in intensity at the start of transmission ('ramp-up'). Here, we conducted experiments in which tagged humpback whales were approached with a ship to test whether a...

Naval sonar disrupts foraging in humpback whales

Modern long-range naval sonars are a potential disturbance for marine mammals and can cause disruption of feeding in cetaceans. We examined the lunge-feeding behaviour of humpback whales Megaptera novaeangliae before, during and after controlled exposure experiments with naval sonar by use of acoustic and motion sensor archival tags attached to...

Disturbance-specific social responses in long-finned pilot whales, Globicephala melas

Social interactions among animals can influence their response to disturbance. We investigated responses of long-finned pilot whales to killer whale sound playbacks and two anthropogenic sources of disturbance: Tagging effort and naval sonar exposure. The acoustic scene and diving behaviour of tagged individuals were recorded along with the...

Biological significance of sperm whale responses to sonar: Comparison with anti-predator responses

A key issue when investigating effects of anthropogenic noise on cetacean behavior is to identify the biological significance of the responses. Predator presence can be considered a natural high-level disturbance stimulus to which prey animals have evolved adaptive response strategies to reduce their risk of predation by altering behavior away...

Controlled sonar exposure experiments on cetaceans in norwegian waters Overview of the 3s-project

The 3S2 experiments – studying the behavioral effects of naval sonar on northern bottlenose whales, humpback whales and minke whales

In order to properly consider how behavioral responses to anthropogenic noise affect marine mammals and establish safety limits for sonar operations, there is a need to establish behavioral impact criteria. In order to achieve this, knowledge about how marine mammals might respond, thresholds and durations of responses as well as the biological...

Predator sound playbacks reveal strong avoidance responses in a fight strategist baleen whale

Anti-predator strategies are often defined as ‘flight’ or ‘fight’, based upon prey anatomical adaptations for size, morphology and weapons, as well as observed behaviours in the presence of predators. The humpback whale Megaptera nova eangliae is considered a ‘fight’ specialist based upon anatomy and observations of grouping behaviour and active...

Severity of Expert-Identified Behavioural Responses of Humpback Whale, Minke Whale, and Northern Bottlenose Whale to Naval Sonar

Controlled exposure experiments using 1 to2 kHz sonar signals were conducted with 11 humpback whales (Megaptera novaeangliae), one minke whale (Balaenoptera acutorostrata), and one northern bottlenose whale (Hyperoodon ampullatus) during three field trials from 2011 to 2013. Ship approaches without sonar transmis-sions, playbacks of killer whale...

First indications that northern bottlenose whales are sensitive to behavioural disturbance from anthropogenic noise

Although northern bottlenose whales were the most heavily hunted beaked whale, we have little information about this species in its remote habitat of the North Atlantic Ocean. Underwater anthropogenic noise and disruption of their natural habitat may be major threats, given the sensitivity of other beaked whales to such noise disturbance. We...

The social context of individual foraging behaviour in long-finned pilot whales (Globicephala melas)

Long-finned pilot whales (Globicephala melas) are highly social cetaceans that live in matrilineal groups and acquire their prey during deep foraging dives. We tagged individual pilot whales to record their diving behaviour. To describe the social context of this individual behaviour, the tag data were matched with surface observations at the...

Responses of male sperm whales (Physeter macrocephalus) to killer whale sounds: Implications for anti-predator strategies

Interactions between individuals of different cetacean species are often observed in the wild. Killer whales (Orcinus orca) can be potential predators of many other cetaceans, and the interception of their vocalizations by unintended cetacean receivers may trigger anti-predator behavior that could mediate predator-prey interactions. We explored...

The Severity of behavioral changes observed during experimental exposures of killer (Orcinus orca), long-finned Pilot (Globicephala melas), and sperm (Physeter macrocephalus) whales to naval sonar

This study describes behavioral changes of wild cetaceans observed during controlled exposures of naval sonar. In 2006 through 2009, 14 experiments were conducted with killer (n = 4), long-finned pilot (n = 6), and sperm (n = 4) whales. A total of 14 6-7 kHz upsweep, 13 1-2 kHz upsweep, and five 1-2 kHz downsweep sonar exposures, as well as...

Pilot Whales Attracted to Killer Whale Sounds: Acoustically-Mediated Interspecific Interactions in Cetaceans

In cetaceans’ communities, interactions between individuals of different species are often observed in the wild. Yet, due to methodological and technical challenges very little is known about the mediation of these interactions and their effect on cetaceans’ behavior. Killer whales (Orcinus orca) are a highly vocal species and can be both food...

Cross Media in cijfers. Cross Media Monitor 2010

Social Structure of Risso's dolphins (Grampus Griseus) at the Azores: A Stratified Community Based on Highly Associated Social Units

In this study, we present for the first time a model for the social structure of Risso’s dolphins (Grampus griseus Cuvier, 1812). Over the period 2004–2006, 1028 Risso’s dolphins were identified at Pico island, Azores. Individuals sighted on 10 or more occasions were included in the analysis of social structure (n = 183). High resighting rates...