My Experience as a Seasonal Project Officer with the Scottish Invasive Species Initiative

Owen Barron, Seasonal Project Officer, SISI Project, October 2022

We asked Owen Barron, Seasonal Project Officer for the Esk and Tay catchments, about his experiences working on the SISI project this summer.

My experience as a Seasonal Project Officer with the Scottish Invasive Species Initiative can be summarised in three words: physical, challenging and rewarding.

After following the project from the outside as an interested Animal & Conservation Biology student, then as a mink raft volunteer through my previous job as a Countryside Ranger, when I saw the job advertised I knew I had to get involved. I started my role on the 25th of April, just before the plant control season started in earnest.

Seasonal Project Officer Owen spraying giant hogweed

The project aims to increase native species biodiversity through the eradication of invasive non-native species. The invasive species I have mainly been dealing with include giant hogweed, giant knotweed, Japanese knotweed and American mink. Through no fault of their own, they find themselves here in Scotland and outcompete native species. Invasive non-native plants often grow in monocultural stands, which reduces native species biodiversity – and that’s where we come in!

First Thing’s First – Training Time!

When I started in post, I didn’t have the required qualification for pesticide application, so gaining this was an essential first step.  A course was quickly booked for me free of charge (as it can be for volunteers wishing to get involved with the project) and I completed the two-day training sessions.  I was nervous of the assessment after theory training, but after a few nights of study I felt much more at ease and completed the practical assessment without too much difficulty.   

I now have my herbicide spraying and injection certificates, which I will have indefinitely. Within a couple of weeks of starting my new job I’d gained a new professional skill and was ready to take this into the workplace!

Getting ready for some pesticide application practice during training – alongside volunteers and land managers who are working with the project

I work in the Tay and Esk catchments (Perthshire and Angus) alongside Project Officer Mark Purrmann-Charles. I was eased into the role with an introduction to the project area and shown around the offices, but then I was sorted out with equipment and we were straight out to survey the North Esk River for giant hogweed. When covering such a vast area and balancing several roles at once, time really is of the essence, and the mink and invasive plants don’t wait around for you!

Giant Hogweed Season

A crucial factor which allows us to cover different species is that their control seasons come at different times of the year. We start off the year with giant hogweed, with the control season running from May until July.

Cutting off giant hogweed flowers (from a safe distance) to prevent seeding

I was nervous about getting up close to these massive plants as I had heard stories about them and researched them online – they had turned from plants into monsters in my mind!

Another thing I realised at the start of the job was that I was not as fit as I thought I was. We tend to cover several miles in a day, trekking over difficult riverside terrain whilst wearing full protective clothing – this keeps us safe when working with chemical pesticides and also from the brambles, nettles, thistles, giant hogweed, and anything else that decides we are the enemy! On a warm day in June, it gets very sweaty and challenging. Without our volunteers who join us for the larger areas we would really struggle to treat all the areas in time before the plants set seed.

Getting set up with volunteers to spray some giant hogweed at Canterland beat (North Esk)

Throughout June and July I was mostly working on the North Esk and the South Esk, which are my local rivers – I’ve seen so much more of the wild spaces on my doorstep and explored places I never even knew existed prior to this role. I can proudly say I survived my first ever giant hogweed season and with no sap burn!

American Mink Control

American mink activity picks up around August as this is the time of year when juvenile mink start to find their own territory. My focus shifted from giant hogweed control to getting in touch with the 70+ mink volunteers throughout Angus, Tayside and Perthshire, to see how things were going and if they needed any new equipment.

One challenge I’ve faced is finding my way to some more obscure places and the hardest part has been trying to trust Google Maps. There have been several occasions when Google Maps has tried to lead my poor Fiesta across non-existent roads, through rivers and even changed to a totally different route mid-journey. Despite arguing with the voice coming out my radio almost every day, I’ve managed to get to my destinations and meet many amazing people that support the project and help keep Scotland’s wild spaces beautiful and healthy.

Mink raft set up with volunteer Mike at Stanley Mill – which has now successfully caught 3 mink!

Once a member of the public gets in touch via our website or email, I am responsible for setting them up as a volunteer. I first make contact over email to gain the necessary information (e.g. their address for ‘trusty’ google maps) before heading out to meet them and getting them up to speed with exactly what is involved in being a mink raft volunteer. I help the volunteer to find a suitable location for the raft, demonstrate how the equipment works and complete some registration papers with them. Connecting members of the public to conservation efforts is something I really take pride in doing and it’s brilliant meeting all the people that wish to take part.

Japanese and Giant Knotweed Season

Next is knotweed season, which has seen me through to the end of my seasonal contract and concludes my short but action-packed time with the project. The main area of treatment will be on the River Tay, and I’ll be swapping my knapsack sprayer for a large needle for stem injections. I hadn’t seen much of Perthshire, so I was excited to get started. However, one thing I felt apprehensive about was the flies as I heard they are much worse than on the Northeast coast and I already felt like I was being swarmed! There can be 50 flies pestering me but none at Mark – maybe that’s nature testing me even more to make sure I’m up for the job.

Survey mode – scanning the riverbanks for knotweed stands with Project Officer Mark

After a few weeks of getting up to speed, I was given the opportunity to lead on a control site for Japanese knotweed. I contacted our team of volunteers to see which days they were able to come out, then looking at the weather forecast we scheduled potential dates. On the day I would have to decide whether to go ahead with treatment or not, as the treatment can be ineffective if the plant is wet prior to control or if it rains too soon after, and strong winds also make conditions unsuitable for spraying. I then contacted the landowner to get permission to access and park on the site. We met at the location, got kitted up to start, and followed a rough plan for injecting the larger knotweed stems with neat chemical and spraying the smaller plants with our knapsacks. I was very happy that I was not on my own as it ended up taking much longer than I had anticipated, even with two of us!

After leading on this site by myself, I now realise the importance of surveying and monitoring as these allows you to find exactly where the target species is present and how best to plan treatment days. Follow up surveys are useful to determine if treatment was successful and if any follow-up control is required. If the initial treatment did not deliver the results you hoped for then it is essential to reflect on what factors may have caused this. For example, at my first control area I noted that it was fairly windy during treatment and it rained unexpectedly half an hour after the last section of knotweed was treated – and this was the knotweed which did not respond to treatment as well as the other three sections.

Japanese knotweed site before treatment
Japanese knotweed site after treatment

The weather has been a massive challenge throughout the project as well. You can have the most perfectly planned out control season and be as efficient as possible, but then the wind picks up and you are unable to spray, or the rain comes on and treatment will be ineffective as the pesticide is diluted, or it’s too warm and it’s unsafe to be working in full PPE, and then to top it off the first frost comes earlier than expected – which is the cut-off point for knotweed control season as the plant becomes inactive.

Final Thoughts

A massive factor contributing towards the success of the project is the time that our volunteers put in. Monitoring mink rafts, joining us for tough days of plant control, getting trained up and taking ownership of their own area to control invasive non-native plants – all of this would prove to be too much for a relatively small team of people without the support of our dedicated volunteers.

I have been impressed seeing images of giant hogweed and Japanese knotweed forests 4 years ago and comparing these to the same location today. Seeing native wildflower meadows replacing monocultures of invasive plants is hard evidence of success – and that is what makes all the nettle stings and sore legs worth it.

Off for a bit of spraying

I enjoyed every minute of the job and really feel like I’m part of something making a big positive difference, which is what I put myself through 4 years of university for in the first place! You would struggle to find a role that offers so much experience and conservation action in such a short timescale as a Seasonal Project Officer with the Scottish Invasive Species Initiative does.

Owen is now a Conservation Officer with Saving Scotland’s Red Squirrels – working in the Tayside and Angus areas. Thanks for all your hard work Owen and best of luck with the new job!


To find out more about the Scottish Invasive Species Initiative and how to get involved, you can visit our website, follow us on social media or contact us on sisi@nature.scot

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