As far as we know, sonar operations as part of Joint Warrior ended on Thursday, when exercises were completed in the Minch and the outer approaches to the Moray Firth.
We have been informed that the Navy did not conduct active sonar operations within the Moray Firth (drawing a line closing Duncansby Head and Fraserburgh Head). Five of the ships involved in Joint Warrior operated within the vicinity of the Moray Firth and we understand that the pre-determined mitigation measures were enforced (see previous blog!).
A number of concerned individuals, the Cetacean Research & Rescue Unit and WDCS volunteers at our Wildlife Centre in the Moray Firth conducted land and boat based surveys during the exercise period. We are not aware of any incidences of unusual cetacean behaviour.
But of course absence of evidence is not to be confused with evidence of absence. Monitoring and recording the animals themselves is difficult enough (as many of you will know!) and recording potentially negative impacts is an incredible challenge. As an example, the worlds’ most expensive collaborative research project (costing millions of US dollars) to investigate the impacts of naval sonar took place on a navy range in the Bahamas last year. It took a whole field season to obtain response data to sonar in less than a handful of whales – and you can imagine that the weather in the Bahamas is more obliging than it is in Scotland during October! And yes, responses to the sonar were observed in some, but even with this evidence, interpreting what this response means to the animal in the short and long term is a very difficult job. As well as changes in observable behaviour, much more subtle responses - including stress - will go unrecognised.
There are many acoustic monitoring devices recording the vocalisations of the dolphins and porpoises using the Moray Firth at present, thanks to a project that is being conducted by Aberdeen University and funded by the UK government (to help decide if it is appropriate to allow a major seismic survey in the Firth in 2010). We understand that these devices will not provide details of any sonar activity, but with the assistance of the navy in determining when sonar activities took place, they may help us to determine if any animals in the vicinity of the exercise responded vocally. In addition, WDCS has its own passive acoustic receiver at our wildlife centre in Spey Bay: