Iain Semple, Stirling

For over 30 years, Iain Semple has been looking after one of the oldest freshwater fish farms in Scotland.

Since graduating in 1981 with a degree in Biology and Environmental Sciences, Iain has worked and resided at Howietoun Fishery, Stirling, in what he describes as his ideal job. “I count myself as very fortunate,” he admits. “I have a huge amount of variety in my job and plenty of contact with a large customer base, which is one of the most satisfying things of all.”

His passion is almost palpable. “It’s a continual buzz for me,” he says, “almost a religious thing.” Eyeing an osprey circling overhead, he explains: “The biggest pleasure that I have here is that this site produces a product, makes a profit and also enhances the surrounding wildlife – it’s not unusual to have 4 or 5 ospreys here at the one time and we give them a limited degree of access to the ponds by not covering all of them with nets. We also have herons, otters, cormorants and in the summer there are broods of ducklings, moorhens, kingfishers and all sorts of small songbirds that utilise the water margins.”

Aquaculture is an industry of growing importance in Scotland, providing valuable jobs and income for the economy. Scottish salmon accounts for by far the largest proportion of Scotland’s fish farm production, weighing in at 162,223 tonnes in 2012. However, aquaculture in Scotland also includes farm production of brown trout, rainbow trout and Arctic charr destined for the table or for re-stocking fisheries.

Iain explains that both brown trout and Atlantic salmon smolts are available from Howietoun, as well as non-breeding triploid and all-female stocks if required. Since it was bought in 1979 by the University of Stirling’s Institute of Aquaculture, the site has been used for the practical training of British and international students in modern aquaculture techniques, as well as operating on a small commercial basis. This is very much in keeping with the work of the 'father of scientific aquaculture' and founder of Howietoun, Sir James Maitland, who pioneered fish farming techniques through scientific experimentation and set the standard for modern fish farming.

Iain explains that the primary consideration of fish farming is water quality: “The product that we produce – live fish – can only be produced with good quality water. It’s fundamental that the water we use is of the highest possible quality and, from a sustainability viewpoint, the water that we put out is at least as good.”

Howietoun is fed with water from Loch Coulter via the Canglour Burn and features terraces of ponds built with linking channels designed to prevent siltation and provide sufficient aeration of water. “Using these ponds in a sustainable way is why these ponds are still functioning,” says Iain. “The process here is very, very natural. We’ve learnt over the years that we have to work within the constraints of the surrounding environment.”

Fish waste presents an ongoing challenge: “By growing livestock in the water you inevitably introduce excess nitrogen and phosphorous within fish waste. But the positive thing is that because we are using ponds without liners, they act as biological filters. Providing we don’t overstock these ponds, we don’t end up with any waste at all – it’s all broken down within the pond and produces food for the fish in the form of invertebrates, snails and all sorts of larvae.”

Through rotation and thinning of stocks, there is an annual cycle of increased productivity in the pond: “The fish end up with good fins, with good colours and they look vibrant and healthy. If you avoid stress, 99 times out of 100 you avoid problems that might otherwise face you as a producer of livestock.”

Iain believes that every land management practice will impinge upon the water that flows through a catchment: “Farming, forestry, fish farming – they all have effects upon the water, and providing no-one over-utilises the water to the degree that it is degraded, the water is of perfect quality for every type of land use. The challenge with water is to ensure that water stays as pristine as it currently is and if it’s not pristine you take steps towards remedying that. A lot of that is down to how we educate land managers and users of water.”

Iain is philosophical about our role as custodians of our environment. “Ultimately, you’re only passing through, you only own the land for a short period of time. Nature’s going to continue, but only if we treat things with respect and with knowledge of what’s good and what’s bad.”

Looking at the bigger picture, Iain is passionate about managing our resources with sustainability in mind. “The future of our species is going to be severely impaired if we don’t look after our water resources in a sustainable way. To do it in a holistic way requires continual refinement of technique and our existing knowledge base.”

Iain recognises that globally we, as a species, are polluting our oceans with waste on a grand scale and potentially causing irreparable damage to our food resources. He believes that we all need to play our part: “If you think locally that translates into a benefit for the world. If you continually focus on what you can do in your own patch that then helps the world at large.”