Silurian Survey Round Up: July-October
The second half of the 2018 survey season on board Silurian had surveys depart from our hometown of Tobermory, as well as departures from Ullapool - our most Northerly rendezvous point. The Ullapool surveys allowed us to explore the northern part of our research area. Despite some unsettled conditions we covered an impressive 1843 nautical miles (3413.3 km) over ten surveys, collecting visual and acoustic data through our Cetacean Research Programme.
On board these surveys we had some amazing experiences and wildlife encounters, with 634 sightings of marine megafauna involving and incredible 2875 individuals. Nine marine mammal species were recorded including 337 sightings of cetacean species and 232 sightings of seals, as well as twelve basking sharks!
One particularly special encounter this season occurred on HWDT12; with a sighting of 25 pilot whales, a first for Silurian in our 16 years of surveying! Long-finned pilot whales can grow up to 7.6 m and we certainly had some big males in the group, which are distinguishable by their large, broad dorsal fins. Some of the individuals raised their heads vertically out of the water to have a better view of Silurian, a behaviour known as spy-hopping. We were even able to hear them underwater as they swam repeatedly around the vessel, recording an incredible array of clicks and whistles.
Another day on board this season highlighted the incredible biodiversity seen in the Hebrides. On HWDT10 on a magic Monday we encountered seven species of marine megafauna in less than 8 hours! We had common dolphins bow-riding, an incredibly close encounter with a feeding basking shark, and even saw a breaching white-beaked dolphin; a day that none of us will be forgetting anytime soon.
Our sixth survey of the season departed from Tobermory and covered an incredible 475 nautical miles (nm) over a period of twelve days, covering a vast amount of our survey area. We even managed to get to Stanton Banks, a series of underwater granite ridges that rise up from the seabed, 124 km west of the UK mainland!
The seventh survey of the season also departed from Tobermory and travelled 294 nm over seven days, covering the Southern reaches of our survey area. We were lucky enough to spend some time with thousands of puffins on Lunga and encountered a pod of Risso’s that included several mother and calves.
This survey was the first of three week-long Teen Team Research Expeditions, providing 16 and 17 year olds with a unique opportunity to live on board Silurian and train to be marine mammal scientists. We covered 177.5 nautical miles. Harbour porpoise were the star of the show, making up 56% of the encounters.
The second of our Teen Team Research Expeditions concentrated on the waters around the small isles. The survey showed the amazing biodiversity of the area with six different species of marine megafauna, including and close encounter with a Basking shark.
Our last survey of the season departing from Tobermory was one of two halves. Unsettled weather at the beginning of the survey forced us to shelter around the east coast of Mull enjoying some beautiful anchorages along the way. However, sunshine greeted us as we went into the second half of the survey. Magic Monday occurred when we crossed the sea of the Hebrides, encountering seven species of marine mammals - in one day!
September saw the first of our Ullapool surveys, our most northerly rendezvous location. We covered 290 nm, with the citizen scientists spending over 48 hours of effort, as well as collecting over 43 hours of acoustic recordings.
The second September survey running from 27th-5th October covered a whopping 159.8 nautical miles, despite some unsettled and unwelcoming Scottish weather. However this survey was also a first for Silurian, with the first sighting of Pilot whales in our 16 year history.
We ended the season on a high, with a fantastic week long survey from Ullapool. We covered 159.3 nm, encountering five species of cetaceans and 1052 birds! We also experienced some spectacular skies, with gorgeous sunsets, sunrises and even the northern lights! What a way to finish a spectacular season!
The last of the Teen Team Research Expeditions left from Ullapool on the 13th October. Over the week we travelled 93.6 nautical miles, collecting visual and acoustic data in the waters around Wester Ross and up to Lochinver. In total we had five sightings, encountering three different species – common seal, harbour porpoise and common dolphins, as well as a speedy unidentified dolphin and an unidentified fin!
Massive thanks to all of the the citizen scientists who have joined on board so far- we couldn't collect the vital data without you! You have all been so fantastic this year!
Thanks also to Scottish Natural Heritage who help fund the data collection programme aboard Silurian.
Feeling inspired to get involved with our marine conservation efforts? We have just released the dates for our 2019 season, come and join us on board for your chance to contribute to our research and encounter some of the cetaceans in our waters.