WP4: Sensitivity of Marine Life


Main objective

The main objective of WP4 is to provide assessment of the impact of shipping noise on marine life by:

  • An identification and characterisation of areas sensitive to noise
  • A review of existing regulations on marine life conservation
  • Bioacoustics experiments conducted on representative marine species: fishes, invertebrates and marine mammals to assess their sensitivity to ship radiated noise
  • Integrating marine species sensitivity to noise in predictive models (bioacoustics criteria)

Task 4.1 Identification and characterization of noise sensitive areas

In this task, we used the current legislation and definitions from IMO, the Habitat Directive, the Bird Directive, and Natura2000 as well as the database from Natura200to build the distribution map of sensitive species to noise. Then, using the AIS database at EU waters level, we also plotted ship density as an additional layer to define the criteria to be used to select representative marine areas of interest for the AQUO Project. The information collected helped to define the scenarios to be used for the AQUO noise footprint assessment model developed in WP1 (see Task 1.3).

Deliverable D4.1

Task 4.2 Noise sensitivity of marine life

This task is subdivided into three subtasks.

In the first subtask T4.2.1, an experiment was conducted to study the long term behavioural reaction by wild cod to ship noise and describes the character and scale of the reaction. This study took place on the Swedish west coast with a small local cod population equipped with acoustic tags. For the ship noise disturbance, a Swedish Coast Guard ship was used. In general, the observed reactions in terms of horizontal swimming were smaller than expected and what the study was designed for. However, the scale of reaction will not lead to an increase in energy consumption due to the disturbance. This study was able to track fish with good accuracy. This is one of the first studies of its kind that tracked free swimming fish over a long period of time around an acoustic disturbance event.

Deliverable D4.2

In the subtask T4.2.2, the study focused on ‘the masking effect of ship noise on hearing in harbour porpoises’. It consisted of a series of auditory measurements in some individuals held at two facilities in the Netherlands. Their hearing sensitivity was first tested in an un-masked situation by measuring auditory brainstem responses to repeated acoustic stimulation. Subsequently, these measurements were repeated in the presence of red noise, resembling the acoustic underwater signature of ships. The results show that ship noise has the potential to mask the auditory perception of harbour porpoises over the entire frequency range tested in this study. Furthermore, the conclusions of this study recommend that, by contrast to the MSFD criteria focusing only on low frequencies, that higher frequency ranges should also be considered.

Deliverable D4.3

In the subtask T4.2.3, offshore noise exposure comparative experiments on common cuttlefish were conducted in similar conditions as during laboratory studies conducted before AQUO project (in terms of sound characteristics, received levels and time exposure). Particle motion measurements were also conducted both in laboratory conditions, as well as at the same locations and depths where the individuals were exposed at sea. Scanning electron microscopy revealed similar injuries in the inner structure of the statocysts, as those found in cuttlefish in previous experiments.

Deliverable D4.4

Task 4.3 Criteria for bioacoustic sensitivity of maritime areas

In this task, it is first described how the different zones of influence, for the marine life to its whole, can be expressed. Then, thanks to the joint work of acousticians and biologists, more details are given, establishing the key links between acoustic levels and effective impact. The focus is hereafter made on three species representing different representative species of European maritime areas (Harbour porpoise, Atlantic cod, and Common cuttlefish).

Deliverable D4.5

WP4 Partners: