Through force of habit, I’m getting restless at my desk. It’s not just that the wettest winter on record seems finally to have given way to some spring sunshine. I’m longing for a wind-swept rock in the Firth of Forth, for that pungent mix of guano, sea salt and half-digested fish, for walking up past the lighthouse before it’s turned off in the morning and coming back once it’s back on for the night. Why? Because it feels like home!
I finished my PhD this autumn (you may call me Dr Hanna), which involved hefty amounts of fieldwork on the Isle of May. For the last four years, this has been the time of year when I start wondering what the shags along Scotland’s east coast are up to. In early March, as “our birds” start coming back to nest on the island, we start to get an idea of how the breeding season might play out. That’s been the time to start getting together equipment, finalising research plans, and stocking up on 3 months’ worth of normal life in preparation for being tied up in monitoring and experiments until July. This year, having progressed to new investigations, I won’t be resident on the island, and it takes some getting used to.
During my PhD, I was interested in finding out about how parasites (mainly worms in the stomach) affect the shags’ behaviour and breeding success. Parasites are an important part of animals’ lives – more or less every wild animal is infected with several sorts of parasites – but few people have investigated how seabirds react to infection. Seabirds are important “indicator species” that can show us what’s going on in the oceans: they are relatively easy to find and monitor, and because they are at the top of the marine food web, they are affected by changes further down the food web, which can be more difficult for us to measure. To get the most out of seabirds in this sense, it’s important that we understand as much as possible about everything that influences their behaviour and breeding success – including parasites. Around the world, numbers of seabirds are going down, so also for their own sake we need to know how they are influenced by parasites and diseases. In fact, after the winter of 2012-13 when about half of the breeding adult shags from the Isle of May died because of unusually stormy weather, the experimental work I did in previous years would not have been possible as I would have had too few study subjects to reach reliable conclusions.
Using lots of different sorts of data, I discovered several new and exciting things, which boil down to: parasites are very important to how shags breed, grow and behave. (If you’re interested in details, they’re on my website: hanna.granroth-wilding.co.uk ) As well as accomplishing some cool science, I had an amazingly fun time and got to know some superb people. My work involved learning to find my way around hundreds of shag nests, clambering around the rocks, watching and measuring birds, and very efficient timing and organisation (think multi-coloured timetables the size of a dining table). And, of course, eating: no field season is complete without lots of good food! At dinner time, everyone comes in from being scattered about the island, so it’s an important social occasion, as well as essential to fuel our long days. A typical research day for me in the busiest part of the season started between 3 and 4 a.m., to get out before first light, and finished around 10 p.m., after dark. Might not sound much fun, but because everyone works like mad things, the mutual sympathy really brings the group together! The way the group gels can make or break a field season, but in my experience one of the marvellous things about Fluke Street (where we stay on the island) is that it is always populated by happy, sociable, interesting people. It has been very educational, not just enjoyable, to experience how the wardening team and research scientists work together and get along. For me, much of the uniqueness of the May – as a place to live and work, as well as an internationally important conservation area – stems from this co-operation.
I know I’ve been extremely fortunate to have had the opportunity to work on the May, and I’m very grateful to everyone who made that possible. Now, I’m using everything I learnt there to address new challenges in ecology. Onward!