Life as a marine biologist can be interesting; it’s always a challenge to try and put names on everything we see underwater. It can be fun; I get to go diving all over the UK and have seen bits of Scotland very few others have visited. It can be uncomfortable; measuring oysters in 2m of water in Loch Sween in January, snow on the ground, for instance. It can become routine; lying on the seabed or sitting on the shore counting small things in quadrats for several days in succession springs to mind. It can also be deadly boring; I’ve just spent a week copying and pasting data from a spreadsheet into a database. Just once in while though, we find something exciting. These things rarely fall into the Great White Shark category and boat skippers have been known to watch in total bemusement as we rave about some tiny speck of sealife rescued from the deep in a polythene bag.
For example, in the early 1980’s (yes, that long ago), we came across a spectacular anemone that none of us had seen before in a muddy hole amongst a group of islands in the Firth of Lorn. The next few days were spent devising a suction sampler in an attempt – successful – to collect an animal for positive identification. It turned out to be Arachnanthus sarsi, known only from a single damaged specimen collected from Trondheim Fjord around the turn of the century. Well, we thought it was exciting. Divers have since found it in a few scattered locations around the British Isles.
Last year we carried out a survey in Loch Sunart for SNH. Loch Sunart is a Special Area of Conservation and, as the UK has a responsibility to report to Europe every 6 years on the condition of its SACs, we were carrying out the Site Condition Monitoring. Part of this required a remote video survey – dropping a video camera on an umbilical at locations throughout the loch. On one of these drops in Loch Teacuis, a sheltered side arm of the loch, we saw a large colony of worms, Serpula vermicularis. The excitement generated by this sighting was considerable! Subsequent visits with snorkelling and diving gear found colonies all along the side of the loch.
The reason for the excitement was that, although the worm is very common as solitary individuals, it rarely forms these colonies or reefs. The only other place in the UK where they are known is Loch Creran – until now, of course. Elsewhere there are reefs in a site in Ireland and one in Italy. Any creature that forms reefs underwater provides a habitat for other species and so the diversity of a site can increase considerably. Why they have suddenly appeared in Loch Teacuis is something of a mystery. Of course, the various surveys over the last 15 or 20 years could have missed them, as underwater visibility means that underwater surveys can only ever take a snapshot view of a small area. Or the colonies could have grown up in the last few years. This find though was exciting enough to make the national news.
One advantage of designating sites such as this as SACs is that developers have to take notice. A few years ago, the Victorian railway bridge across Loch Creran was replaced with a road bridge to shorten the road from Oban to Fort William and I was involved as a consultant on the project. In a major recycling project, the old railway spans were lifted off intact to be used elsewhere and an enormous barge, the Mersey Mammoth, was brought in for this. As the barge was only slightly smaller than the channel, there was no room for navigational error. The entrance to the channel is fringed with Serpula reefs and there is a horse mussel bed in the centre so it is a very sensitive site of international conservation importance. Us biological consultants did have some influence on the way the project was carried out; for example, they changed the mooring method for the rig and barge so as not to drag heavy anchors through the Modiolus bed. However, the workmen on the site couldn’t take the idea of important worms v. road bridge entirely seriously and I became known as the Worm Police. We buoyed the area of channel the barge could use and on the day of the span removal, yellow hat on head, I was there to represent the interests of the worms. What I would do if the barge went aground, I had no idea. Jump up and down and shout “Mind the worms!” perhaps.
Anyhow, it all went smoothly and there was a collective release of breath and relaxing of shoulders from the engineers and the bridge spans were finally attached to the sides of the barge. I hadn’t appreciated how tricky an operation the whole thing was, never mind the worms.
So the next time you drive from Oban to Fort William, think of the spectacular worm colonies and the horse mussel beds beneath the bridge.