This blog post is part of SMRU Consulting’s #ThrowbackThursday (#TBT) series. On Thursdays we’re going to posting about projects from way back when, many of which are part of developments that are consented or up and running. This #TBT blog is about our development of a real-time monitoring buoy to provide live detections of dolphins and porpoises during a port construction in the UK.
In 2014 SMRU Consulting Europe, in partnership with St Andrews Instrumentation Ltd and Marine Revolution, provided a special kind of underwater noise and marine mammal monitoring and mitigation at the site of the Queens Dock expansion, near Invergordon, Scotland. The project scope was to deliver a previously unheard of innovative marine mammal mitigation system.
The purpose of this project was to provide a system capable of Passive Acoustic Monitoring (PAM) in real time relaying information using WiFi so it could operate by itself. This allowed the system to provide a means of mitigation for harbour porpoises and bottlenose dolphins. Specifically, the regulator determined the requirement for monitoring of underwater noise levels and the presence of dolphins and porpoises whilst construction activities were underway (due to the protected state of the cetacean populations in the region). Standard visual MMO mitigation was considered challenging in this area due to the proposed plan for construction to continue around the clock (24/7) , autumn/winter daylight conditions and bad weather (i.e. rough conditions, fog, rain/snow, etc.). Therefore, in this case, the combination of visual and acoustic methods was critical to the marine works being completed whilst minimising harm to wildlife. The importance of reliable, proven PAM systems here was greater than in other locations and situations.
Pictured above: A screengrab from the PAMGUARD customised set-up developed and employed showing the mitigation zones, bearings to vocalising animals (top left), the bottlenose dolphin sounds (top right) and the porpoise system (bottom) all running live at the same time.
Working with SA Instrumentation, Marine Revolution and the Cromarty Firth Port Authority, we developed and installed a single buoyed PAM unit (with Decimus installed) at the site, with a special 3-hydrophone array suspended underneath it in the middle of the water column. The unit detected cetaceans (bottlenose dolphins and harbour porpoises) in real-time from the system deployed 1 km offshore. The 3-hydrophone array deployed beneath the buoy (fitted with a specialised custom digital compass) provided bearings to the animals as they made sound so that the team could determine which direction the animals were and ensure that animals were not harmed. The PAM system also had integrated alarm triggers to notify the PAM operator of the presence of vocalising animals. In addition, the unit measured underwater noise levels and sent them to the land control station in real time using WiFi so that the team didn’t need to collect the data – it was delivered to them! All of this providing confidence that the marine works were within regulatory limits. All the data were also stored on land and online for later audit and quality control. We fitted the unit with solar panels to keep the unit powered (and provided a separate charging system in case it needed a boost in the dark winter!).
This system allowed the developer to carry on with their development in the most cost-effective manner possible (by reducing delays whilst providing top-notch environmental protections).
All in all it was a pretty incredible system that we developed and delivered. It took a significant investment from all those involved but it showed what can be achieved!