Two of Ocean Science Consulting’s directors, Dr Victoria Todd and Ian Todd, attended the fourth international The Effect of Noise on Aquatic Life conference (AN2016), held in Dublin, Ireland, 10–15 July 2016.
The conference covered a broad range of topics related to the impacts of man-made noise from regulatory, industry and academic perspectives, which makes for a lively mix when it comes to discussions. The last Aquatic Noise conference (held in Budapest) was in 2013, so it was interesting to see how research and regulatory guidelines have progressed. In short, the focus this year was on invertebrates, which surprised just about everybody there.
Research of interest: highlights
Ocean Science Consulting (OSC) is of course, very interested on research involving direct impacts on marine mammals, but because impacts can also be indirect and impacts are all interlinked, research regarding sound levels in the ocean and impacts of noise on potential prey is equally crucial.μ
Some fascinating work was presented by Dragon et al. (2016), who found that the radius of avoidance around pile-driving activities shown by harbour porpoises (Phocoena phocoena) decreases as wind speeds increases, probably due to a natural ‘bubble curtain’ effect. Another research group investigated the activity of harbour porpoises around a research platform in the North Sea and found a high rate of occurrence (we’ve found similar patterns around oil and gas installations). An automated visual detection algorithm was also developed to concurrently detect harbour porpoises visually, though this was only possible in good visibility (Ludwig et al. 2016). From a more technological standpoint, research comparing results obtained from two different technologies (C-POD vs SoundTrap) when investigating the influence on shipping noise on harbour porpoises. The two technologies gave drastically different results, although it is not yet clear why (Sarnocińska et al. 2016). Something to keep an eye on!
A good number of talks and posts presented data regarding noise levels around different activities, such as during diamond-wire cutting (Pangerc 2016) and mapping shipping noise in the western North Sea (Farcas et al. 2016). Research around noise levels in the ocean helps to refine sound propagation loss models often used to determine mitigation zones for marine mammals around loud offshore activities. Various aspects of the US National Oceanic and Atmospheric Administration (NOAA) Ocean Noise Strategy were presented, including their assessment of long-term trends in underwater soundscapes (Gedamke et al. 2016; Harrison et al. 2016).
Fish are also susceptible to impacts from noise in the oceans, and as a food source for many marine mammals, effects on fish populations can affect marine mammals populations. Some interesting research looking at effects of noise from a small boat on temperate reef fish in New Zealand was presented. Fish numbers and activity outside a marine reserve decreased significantly in the presence of boat noise, whereas fish within a marine reserve did not show much behavioural response to the boat noise (Mensinger et al. 2016). A tool to predict impacts of anthropogenic noise on fish, the Hydro-Acoustic Model for Mitigation and Ecological Response (HAMMER) was also presented (Bruintjes et al. 2016).
Abstracts from all the presentations and posters are currently available on the conference website.