Icelandic Seabird Adventure Part 2/2

This is quite delayed as I’ve been busy catching gannets in Wales and preparing to talk gannets at the Seabird conference. Having carried out Iceland’s first ever gannet GPS tracking in the lovely Vestmann Islands (click here for part 1), Freydis Vigfusdottir (and I headed along the stunning south coast to our main study site.


Our target was Skrudur, a seabird island with a huge puffin colony and a decent number of gannets to work with. We met with the very experienced ringer Óli, who has been going out to Skrudur to ring seabirds for the last 25 years. We were given a lift out to the island by the very hospital farmers at Vattarnes. We moved into the ‘5 Star Hotel’, which looked a bit like 2 beach huts with walls made of plastic bags, inside a cave. It was quite a long hike to the colony through thigh-high tussocks, collapsing puffin burrows and rope-aided scrambles, but well worth the effort. The colony was stunning with a background ice-covered mountains and the constant whirring flutter of puffins all around.

On day 2, we deployed all 10 sets of 3D loggers and 4 GPS tags – go team! On days 3 and 4, we went to the gannet colony first thing in the morning and again in the evening to recapture returning logger birds (painted pink for easy ID).


During the middle of the day, we carried out Óli’s main mission – to ring as many seabirds as possible. We went to some guillemot spots and caught all the birds within reach with a noose on a stick – it was a lot of fun. Some of the ringed birds were at least 25 years old! We also ringed kittiwakes, razorbills, and 1 Brunnich’s guillemot, but the black guillemots are too difficult to access, and the fulmars were left alone as they spit a foul-smelling oil if you go too close.

We retrieved all the loggers except for 1 GPS tag, as the bird was extremely jumpy. There are always one or two birds that just will not be captured again. It is annoying to lose the device, but, as we attach them to the feathers, they naturally fall out so the bird won’t be stuck with a tag on its tail for very long. Having recaptured all the birds we could, we were picked up at 10pm on day 4 – one benefit of 24-hour daylight! I very much appreciated a warm shower and real bed to sleep in.


Mission complete!

This slideshow requires JavaScript.

Our 670km drive back to Reykjavik was made enjoyable by stunning weather and a few sight-seeing stops. Seeing a group a 9 post-breeding female red-necked phalaropes was awesome, but the highlight of the journey was Jokulsarlon, an absolutely stunning glacial lake with little icebergs floating across it. On the shore was a busy arctic tern colony, which was harassed by awesome great and arctic skuas.

I’ve definitely fallen for Iceland, and will have to go back soon!



Gannet-catching Viking Style – Iceland Part 1/2

It’s fieldwork time again, and this year I’ve had the incredible opportunity to track gannets in Iceland with Freydís Vigfúsdóttir of the University of Iceland and The Icelandic Institute of Natural History. Some gannets eat fish discarded from fishing boats. Iceland is a particularly interesting place to track the gannets as there is more accessible data on the fisheries, so we can better study how the gannets interact with vessels. Yesterday we took a day trip to Hellisey to deploy the first ever GPS loggers on gannets in Iceland! Hellisey is one of the Vestmannaeyjar archipelago– a series of volcanic islands, the newest of which (Surtsey) popped out of the sea in 1963 and was very quickly colonised by nesting seabirds. We were able to work on Hellisey as Freydis, who grew up on the main island of Heimaey, has developed good relations with the puffin hunting clubs and the people from the Vestmann Island Research Centre who took us out on a boat.


After a stunning boat trip to the island, I discovered that getting to the colony was “interesting”, involving an intimidating-looking chain ladder (Freydis’ photo below). I was a little worried about keeping up as I’m still recovering from a broken wrist. But, I was in good hands and we made it safely to the top by hoisting the kit on a rope.




A great lunch of flatbreads dried fish and banana bread.

We looked for breeding birds with white fluffy chicks as these will be the most likely for the bird to be recaptured later on. Freydis caught our first gannet from the top of the cliff – a momentous occasion! Despite having to stop for rain to pass, we reached our target of 8 birds in plenty of time. Freydis will return to retrieve the GPS loggers and if all goes plan, we will have some exciting new data.


1. Too big                           2. Too small (also a dinosaur)               3. Just right!


Gannet-catching Viking style has been fantastic so far. I’ve already had the chance to enjoy the atmosphere of watching the England football match on the big screen in Reykjavik, climb Eldfell volcano (still warm after erupting in 1973) and walk in the bird-filled lava fields, and enjoy Freydis’ mum’s great cooking. Our next stop is the main target of our trip – Skrúður Island, where we will be doing some 3D tracking with GPS, altitude and acceleration loggers, so watch this space!



Eldfell volcano, with a view of the mainland


Golden plover looking stunning on the lava fields

7 reasons to go on a course & how to make the most of it

Update: This blog post evolved into a paper, so if you want even more advice about courses for potential students, course organisers and funders, check it out:

Original post: 6 months into my PhD I went to the brilliant AniMove course on animal movement and remote sensing at the Smithsonian Conservation Biology Institute. AniMove also run an annual workshop / symposium at the Max Planck Institute for Ornithology, Radolfzell, to update everyone on recent advances in movement analysis. On my way there, I had the chance to reflect on the benefits of courses away from your own institution and how to get the most out of it. AniMove is two weeks long – a key advantage over most courses, with the first week covering the taught material and the second for applying new techniques to our own data (never simple!), while an expert is only a raised hand away. But, everything else I thought of could apply to most courses.

Comment / tweet if you have any more!

Not a bad blog post writing spot by Lake Constance on the way to the AniMove workshop

1. Figure out where your project is going.

Nothing focuses the mind better than having to explain your project to a bunch of strangers who know your field.

2. Get ideas for your project or general PhD life

New ideas could just as easily come from the taught material or discussions with course mates, so make an effort to socialise. Every institution has its own way of running PhD programs, so it can be very interesting to see the differences and take home good ideas.

3. Ask the tutors for advice

Ask about your own specific problem early on – this allows the tutors to think on it and they may fit in a workshop, which could help others. Preparation is key for getting the most out of this access to the experts.

4. Meet people in a similar situation to you

Whether you work in a group or work alone on a project / method, which can feel a little isolating, it’s great to chat to people who understand what you are doing without being directly involved. It can also be good motivation to see the progress of students who are further into their PhDs, and comforting to find others have had similar setbacks.

5. Build a network

Keep in touch with your course-mates and tutors, and don’t be afraid to email for advice after the course. Compared to conferences, it’s much easier to get to know people in the smaller group. You may see them at conferences in the future or even end up collaborating – and you never know what might help you to get a job after you graduate.

6. See the world!

Many courses are in interesting places that you might not have thought of visiting (the organisers might choose somewhere nice!), and I highly recommend taking holiday before/after (After AniMove, I had a brilliant time in DC, New York & Delaware). If the course is physically based at a host institution, you can learn a lot from just being there and talking to staff.

7. Oh, and you might learn some actual course stuff

Obviously, the course material is key. You want it to be as relevant as possible, so don’t be afraid to ask lots of questions before choosing a course, and consider options around the world (sometime courses abroad can actually work out cheaper). With notice, the organisers may even be able to add in things for you.

Hike in the Appalachians during AniMove 2015

Text messages from teenage gannets

My third trip to Grassholm this summer with Steve Votier, Greg Morgan, Tommy Clay and Jen Tyler involved an exciting extra task. We know a lot about the lives of breeding gannets and their chicks, but there’s a huge hole in our knowledge with big implications. What do they do between fledging and adulthood at the age of five? Some gannets return to nest the colony they fledged from, but that can’t always be the case, so how do new colonies start?

To investigate this puzzle, Jana Jeglinski, a research fellow from the University of Glasgow, asked us to put out some state-of-the-art GPS loggers on some immature birds in the colony. These solar-powered tags ‘text’ GPS data through the mobile phone network, and will last until the birds naturally moult their tail feathers in a couple of months.

It’s isn’t hard to tell the age of the young gannets as they start of completely black and gain white feathers each year until they reach breeding age. Catching them is trickier – without a chick to defend, these young birds don’t hang around and wait to be caught. But with Steve and Greg’s years of experience and a new two-pronged catching strategy, we captured and tagged 7 birds, including this stunner:

Our ‘teenage’ birds having already appeared in Kent, Ireland, France, Belgium and Holland! So, we’re very excited to find out where they end up in a couple of months.

But enough from me – here’s Jana’s brilliantly informative and descriptive post about her work:

Jana W. E. Jeglinski

Seabird colonies during the breeding season are a full-blown, multi sensual impression, if not impact, of movement, noise and, if you are (un)lucky to be close enough, smell. First your eye takes in everything at ones, birds swarming the sky around the colony like bees and clinging to cliffs literally everywhere. You give yourself time and you will see that this seabird city, this large entity is really made up by tens of thousands of individuals, pairs that work together to bring up their chick, shuttling to and fro from foraging grounds, bringing fish and nesting material, disputing with neighbouring breeding pairs and dealing vicious blows towards unlucky intruders into their miniscule breeding territory. You see some birds clustering at the fringe of this bustle, obviously not breeding, but peering with long necks around, and wonder what they are up to. You can spend hours just watching.

Colonies like this have long been thought to be separate entities, more or less likened to populations, with their own dynamics and their own characteristics. This is reflected in the design of many ecological studies, which are interested in aspects of the behaviour and ecology of breeding birds in one colony, or compare these data between different colonies. For most adult breeding seabird species, the concept holds true: once you have established your breeding territory you are likely to spend the rest of you life breeding in this colony, or trying to. For northern gannets, we know that this segregation between colonies extends also to foraging grounds – adult breeders from different colonies are unlikely to meet each other during their foraging trips as the foraging ranges are highly segregated1. There is also a general understanding of high natal site fidelity – you are likely to breed in the colony in which you have been born.

A two-three year old Northern gannet defends itself against a neighbouring immature bird. Site ownership is still transitory in this age class, and both immatures might have left by the evening exploring other colonies.

A two-three year old Northern gannet defends itself against a neighbouring immature bird. Site ownership is still transitory in this age class, and both immatures might have left by the evening exploring other colonies.

The problem with the concept is obvious, but surprisingly hasn’t found much general attention to date: how do new colonies come about? And why do we observe young colonies to grow much more rapidly than their own production of chicks would allow them to2? The Northern gannet population offers a great illustration to these puzzling questions, having been exploited by large scale harvesting of eggs, chicks and adult birds for centuries, and having recovered since protection around 1900 from a population size of about 70.000 to more than 440.000 breeding pairs and from 16 colonies in 1900 to 51 in 2014 in their North-eastern Atlantic distributional range3.

The key to answering these questions is an almost completely overlooked age class in ecology: teenagers. We might know a lot about chick survival until fledging and about adult foraging strategies, but there is a gaping hole in our understanding of much that goes on in between. For a gannet the hole is big, covering four – five years, because gannets only start breeding at an age of about five years or older. As it turns out, this gap is also very important for understanding seabird population dynamics. Information, e.g. from ring resightings and from a single tracking study4, shows that these young prebreeding birds spend the summer months investigating breeding colonies, the one in which they were born, but also others. We call this behaviour ‘prospecting’, checking out potential breeding sites and, first things first, meeting potential breeding mates on the way. A non-ecologists friends face lit up when I explained this aspect of the gannets’ ecology: “A gap year!”

Two 2-3 year old Northern gannets forming a preliminary and maybe lasting bond through ritualised ‘fencing’.

Two 2-3 year old Northern gannets forming a preliminary and maybe lasting bond through ritualised ‘fencing’.

A very long and influential gap year indeed, and one about which we have almost no direct observations and data. The relevance of these prospecting years lies in the decision making process that takes place during these years: where to breed. And with this one decision, taken by hundreds of thousands of first time breeding seabirds every year, ripened over the course of their prospecting years, the whole population can shift and change. A good illustration is the Norwegian northern gannet population, which did not exist before 1946, because a few birds, amongst them chicks ringed at Les Etac, Ailsa Craig, Grassholm and other UK and Icelandic colonies5 decided to head east and breed on spacious Norwegian cliffs and not in their crowded natal colonies.

Not incidentally, I am specialised in and passionate about the ecology and behaviour of young animals, which is why I chose to investigate the prospecting behaviour and space use of immature northern gannets during my Fellowship at the University of Glasgow. One of the reasons we know so little about this age class is their elusiveness – they might be spotted at the fringe of breeding colonies in so called club-sites, but take off at the least disturbance, or might catch our eye fleetingly out at sea, but that’s not much basis to an ecological study. For real insights into immature movement, we need advanced technology.

I am using GPS GSM tags, one of the cutting edge developments of biologging technology. These small electronic instruments can be programmed to collect GPS positions at predetermined times, and to store these positions amongst other sensor readings, for example flight height, temperature or salinity. They also have a solar panel to reload their battery so that I can deploy them for months at a time. What makes them uniquely suitable to my work is that they also transmit data: equipped with a sim card with roaming ability, they detect mobile phone coverage and send me the data they have collected using the mobile phone network. The reward for deploying these tags on immatures, by no means an easy task, is leaning back and receiving text messages from teenage gannets!

One of the study animals with a GPS GSM tag glued onto of the tail feathers with white TESA® tape. This deployment method is common practice and has been tested in many studies, showing minimal impact on the birds if the tags are lightweight enough. My tags weigh 37g, about 1.3 % of the body weight of the study animals – only half of the suggested upper limit of 3%. The dark top of the tag is the solar panel, which allows the tag to recharge its battery over the next few months. Tail deployed tags fall off when the birds moult their tail feathers, approx. 2 months after deployment.

One of the study animals with a GPS GSM tag glued onto of the tail feathers with white TESA® tape. This deployment method is common practice and has been tested in many studies, showing minimal impact on the birds if the tags are lightweight enough. My tags weigh 37g, about 1.3 % of the body weight of the study animals – only half of the suggested upper limit of 3%. The dark top of the tag is the solar panel, which allows the tag to recharge its battery over the next few months. Tail deployed tags fall off when the birds moult their tail feathers, approx. 2 months after deployment.

I am currently working in three different gannet colonies in Europe, together with collaborators from the Centre for Ecology and Hydrology, the University of Kiel and the Research and Technology Centre Buesum in Germany, the University of Leeds and the University of Exeter. Grassholm in Pembrokeshire, where Dr Steve Votier from the University of Exeter has his long term study site in collaboration with Greg and Lisa Morgan from the RSPB Ramsay, and where Beth, who kindly invited me to write this post, studies adult gannets for her PhD, is one of these colonies. Steve’s team have deployed seven GPS GSM tags on 2-3 year old immature gannets for me in early August, while I was in the field elsewhere. I as most other ecologists adore fieldwork and the deeply insightful bliss of being with and amongst our study species in their habitat. We usually settle with a somewhat resigned air back in front of our computers once the field season has passed. I currently find myself almost skipping to the office every day, brimming with excitement to connect to the server and find another data package received, another aspect of the hidden years revealed!

The year until next field season will see me analysing the tracking data of the immature gannets in detail, investigating the range of their movements and the frequency of their colony visits and why they might visit certain colonies but not others. The results of my analysis and more tracking data collected next year, will then allow me to integrate the network structure of the gannet breeding colonies into a model to understand better the drivers of the dynamics of the gannet metapopulation.

If you want to read more about my work follow me on twitter @JWEJeglinski

References and further reading: 1 Wakefield et al (2013) Science, 2 Moss et al (2002)3 Jeglinski et al. in prep, 4 Votier et al. (2011)5 Barrett & Folkestad (1996)

Grassholm Island: Trip 1

This post is a fieldwork diary about the first of three trips to the Grassholm Island gannet colony – see my first post for the aims of my project.

After months of planning, the day of my 1st field trip finally arrived!

Well, almost.

Studying seabirds often means travelling to stunning, but remote and hard-to-access places. Grassholm Island is no exception. With no jetty or steps, we have to step from the boat onto the rocks with the boat pressed against the cliff, engine on full throttle. This means we must wait for suitable weather and so Steve, Dimas and I set off 3 days later than planned. Normally, the trip starts with a night in the farmhouse on RSPB Ramsey Island with the lovely Greg and Lisa Morgan, who look after both Ramsey and Grassholm. But after the weather delay, we picked up Greg from Ramsey and headed straight out that evening.

The boat trip over was brilliant – Venture Jet’s jet-powered RIB certainly isn’t slow and we caught some air as we crested the huge waves! We saw plenty of puffins, razorbills and guillemots in the water and Manx shearwaters disappearing between waves and wheeling out again. As we got closer to Grassholm, gannets started to appear. They really stood out against the grey sky and, having not seen them for a while, I’d forgotten quite how big they are – dwarfing the herring gulls that seem big enough when they’re after your chips. A huge swirl of birds floated above the island. Photos just don’t capture the noise and movement (and smell!) of a large gannet colony.

After landing on Grassholm, we set up camp and I got to work programming the all the loggers (in ­­my tent as it was raining), which is something we’d normally do in the house on Ramsey. After treating ourselves to a can of beer/cider (a very rare occasion on the island!), we prepared the loggers before bed.

5am felt very early given that we only got to bed at midnight. But I was thoroughly woken up by climbing the hill and arriving at the edge of the colony. I’d seen seabird colonies from the tops or bottoms of cliffs, but this was my first time being so close on foot.

First sunrise on Grassholm, with Ramsey on the horizon

My very first view of the colony - wow!

My very first view of the colony – wow!

We don’t catch any old gannet; we want to track a bird that is about to leave on a foraging trip so the batteries don’t run down at the nest. Steve spotted a target and crept up to the colony with a long pole, carefully hooking the bird round the neck. In the hand, a gannet is quite formidable (as Jude Lane @heyjooode describes in her brilliant blog post on gannet grabbing – click here!). After Steve showed me the ropes, we soon got into a rhythm. Steve ringed the birds, and took measurements and blood samples. Dimas scribed and recorded a map of the nest locations. I attached the loggers with a strong tape and prepped the kit. Greg watched out for the next bird, often catching one while we were still working.

Releasing the birds is brilliant! It involves holding the wings and feet in one hand and the head in the other to keep safe from the sharp end. Being such large birds, they often struggle to get into the air, so you then have to throw it as high as possible so it can catch the wind.

I filmed the release of each gannet for a reason. The acceleration graphs are very useful – measuring g-force in 3 directions at once means loads of interesting detail. But the results aren’t very intuitive, so it can be difficult to tell exactly what is going on. I will match graph to the filmed flapping and gliding, and expand this to the rest of the flight when we can no longer see the bird. The graph below shows how matching dive depth with forwards (surge) acceleration gives us more detail about the dive.

Dive depth & accelerometer data (cape gannet). Adapted from Ropert-Coudert et al. 2004 Ibis 146: 281-90

In the evening, we got to explore some of the other areas of the island so that Greg and Steve could see how different parts of the colony were doing and check out the diets of the birds to see if they are changing over time. Garfish seemed to be the order of the day – easily identified by their green bones. The older parts of the colony are much steeper than the areas we work in, so I could get much closer to the birds without disturbing them (great for photos as I don’t have much of a zoom lens).

4 week old chick

‘Billing’: when a bird returns to its partner, the greet each other by shaking their heads and touching beaks

Day 3 involved deploying only GPS and altimeters on breeding adults as they stay on longer than the new combined loggers. We also put out some GPS tags on suspected failed breeders that were still defending a nest with their mate as they haven’t been tracked before. We also started to recapture some tagged gannets that had returned from foraging, which is the only way to get the data and reuse the loggers. We retrieved 6 tags (one was punctured), which was fewer that we’d hoped for, but great to finally have data. Annoyingly the weather wasn’t on our side again – rain stopped us tagging as the tape doesn’t stick in the wet.

Tim and Henry from Venture Jet picked us up in the afternoon. The low tide meant we had to cross the most slippery rocks, but we got the kit and ourselves safely on board. Conditions were a little choppier than on the way out – it felt like having a bucket of water thrown in your face every 10 seconds! We arrived on Ramsey completely soaked under our waterproofs with boots full of the Celtic Sea, but incredible views of Risso’s dolphins swimming right under the boat were a great distraction. A nice hot shower quickly sorted us out, followed by a lovely evening chatting about past adventures.

We were taken back to the mainland the next morning and headed home for a 4 day break before the next trip. Going out for short trips is really useful for sorting out kit issues – for me it was my trousers deciding that they no longer wanted to be waterproof. The seabirds will soon redecorate my shiny new trousers in a lovely white-ish polka dot pattern to match my tent!

3D gannet tracking & why I’m blogging about it

I’m 9 months into my PhD and have just started fieldwork. After returning from trip 1 of 3 this year, I thought I should write everything down while it’s still fresh in my mind. This blog is a way for me to keep a record of some of my PhD experiences and share it with friends, family and anyone else who might be interested.

Here’s a quick outline of my project plans:

Gannets travel hundreds of miles on a single fishing trip to bring back a meal for their (very hungry) chick. I am looking into where gannets go, how they manage to find fish and travel such large distances. We also want to investigate how they scavenge from fishing boat discards, particularly as the EU is moving to ban fisherman from throwing certain fish overboard. The project site is 13km off the Pembrokeshire coast (Wales) on Grassholm Island – home to 36,000 breeding pairs of gannets, which cover most of the island’s surface in the summer.


Electronic devices are attached onto the birds to record their behaviour: GPS, altimeters, accelerometers and dive recorders. The key will be to use multiple loggers on the same bird to record their flights in great detail. The GPS tracking project has been going on Grassholm for a few years now and we are building up a good picture of where they tend to forage. The map shows a few tracks from last year.

2014 map

The altimeters show the height above the sea, which gives us 3D tracks of the birds’ movements – very cool! The higher you are, the further you can see, but the more difficult it is to pick up scents from the sea. We will find out if these 3D help us pick out foraging behaviour and see how they actually find fish (and fishing boats) in a huge and seemingly featureless ocean.


Dive recorders show the timing and depth of the famous torpedo plunge dives, which will let us know when the birds have successfully found a fishing ground.


The accelerometers measure acceleration in 3 directions, showing even a single wing flap. This will help us to measure how much effort the bird are putting in when they travel and forage, which is very important for trying to figure out how they decide where to go. We will also be able to identify other behaviours, such as telling apart high-speed plunge diving from a slower dive made from the surface.


A post about my first trip to the island will be coming soon!