At any one time, there are approximately 50,000 commercial vessels operating throughout the world’s oceans. If we consider recreational vessels and unlicensed vessels, that number is many times higher. Vessel traffic can impact cetaceans in several ways, the first and most obvious impact is vessel collisions, often referred to as ‘ship strikes’. Ship strikes can be caused by large commercial vessels, which mainly impact whale species, or smaller vessels which can impact both baleen whales and odontocete (toothed-whales and dolphins) species. Collisions with larger ships often go unnoticed and unreported; the incidents that are reported are often of fatal injuries. Collisions with smaller vessels can be fatal, but more often result in injuries that can impact an individual’s ability to undertake normal behavior.
Other issues caused by vessel traffic include noise pollution and disturbance from physical proximity. These issues are harder to quantify as they often don’t have a visual impact. Noise pollution can mask cetacean communication signals and has been shown to alter species’ behavior. Avoidance of certain areas by cetaceans due to the presence of vessels may have impacts on their health or energy expenditure. These cumulative impacts can affect the health and fecundity of individuals which ultimately can affect populations if left unchecked.
We are currently expanding our research focus in several key regions to collect more information regarding the impacts of vessel traffic on cetaceans.
Project Partners
Barbara Galletti, Centro de Conservacion Cetacea
Recent Publications
2022: Olson, G.L., Stack, S.H., Machernis, A.F., Sullivan, F.A., Currie, J.J. Mapping the Exposure of Pantropical Spotted Dolphins and Common Bottlenose Dolphins to Different Categories of Vessel Traffic in Maui Nui, Hawai‘i. Aquatic Mammals 48(2), 167-181. Download PDF
2021: Self, H., Stack, S.H., Currie, J.J., Lusseau, D. Tourism informing conservation: the distribution of four dolphin species varies with calf presence and increases their vulnerability to vessel traffic in the four-island region of Maui, Hawai‘i. Ecological Solutions and Evidence. Download PDF
2017: Currie, J.J, S.H. Stack, Kaufman, G.D. Modelling whale-vessel encounters: the role of speed in mitigating collisions with humpback whales (Megaptera novaeangliae). Journal of Cetacean Research and Management 17: 57–63. Download PDF