I am excited to say that our review in Trends in Ecology and Evolution, after already being available online, is out now in print and is shining on the front cover! I took this photo of this stunning stickleback school while snorkelling in the Bodensee to study their collective behaviour. Read our open access paper here.
Tag Archives: sticklebacks
Snorkling in the Seerhein
Today after work I went snorkeling with some friends from work. We decided to start near the heart of Konstanz and swim down the Seerhein for about one and a half kilometer. I must say people looked a bit surprised to see three guys walking in wetsuit across the street. Although the water was not as clear as I hoped we still managed to see a couple groups of huge Carp, a number of single adult Pike of 1m+ at about 5-8m depth on the river floor, and some huge stickleback schools swimming in the shallows.
New sticklebacks from the Bodensee
Went out again with the boat yesterday to catch sticklebacks. A cold but beautiful day. At first we couldn’t find them where I saw them last week, but soon enough it was clear they were still there but just very well camouflaged against the pebbled background!
With the three of us we managed to catch about 300 of them in half an hour by wading through the shallow waters. Most of the fish are likely 1st-years, but we also caught a couple older individuals that were huge, close to 10 cm!
After mooring the boat, we moved all fish to a large social housing tank at the Limnological institute where they will undergo a anti-parasite treatment for a couple weeks. After that I will move them to our fish lab at the University of Konstanz as well as to outside mesocosms. There they will ‘participate’ in a range of my behavioural experiments focused on individual differences in collective behaviour.
First boating trip on the Bodensee
The past summer, I successfully completed a motorboat course to enable me to drive a motorboat on the Bodensee, required for my ongoing research on fish collective behaviour. I got my “Sportbootführershein” in the post a couple weeks ago, and finally this weekend was able to ‘take the boat out’.
In the cold rainy weather of early November, I set-off with with a good friend on one of the motorboots from the Limnological Institute. The water was considerably clearer than during the summer, providing a visibility of just over 5 meters. It was beautiful being out on the water. However, in the first hour almost being out, we still hadn’t seen our first fish!
We navigated around the island of Mainau, and started exploring the very shallow areas near the mainland. I was a bit annoyed I hadn’t seen any fish yet, let alone any sticklebacks, but when we decided to cross under the bridge leading to Mainau we suddenly found thousands of them!
The water was so shallow that it was necessary to take the motor out, and continue by oars. But this also meant we could observe the swarming fish from very close. Despite sticklebacks being very abundant in the Bodensee, in the autumn and early winter most of them move to deeper waters, likely following the movements of their invertebrate prey. These remaining fish were apparently some of the last ones remaining in the shallows, likely seeking shelter in the shadow of bridge, and I was therefore very happy to have found them.
We spent about half an hour observing their movements and behaviour and I got some good ideas to come back for some more quantitative field measures of their group sizes and compositions. After that we decided to go for a quick snorkel before going back to the harbour.
With my freediving wetsuit, the 11 degrees C actually still felt very comfortable, and I was enjoying the relatively clear waters of the lake. The Bodensee has a very interesting geology, with relatively shallow water on its edges that can suddenly drop almost vertically tens and tens of meters into the deep.
We only snorkeled a bit above a drop-off near the harbour to check our wetsuits and the visisbility, which both passed our expectations. I therefore can’t wait to go back again and take the boat out the lake to catch wild individuals for my experiments, get some more quantitative observations of the sticklebacks and their predators, and explore underwater.
New stickleback in the lab
For my new research projects on the role of individuality in collective movements and decision making at the University of Konstanz, I have been getting new sticklebacks from the Bodensee. Last weekend I went to see them together with my 10mo son! I think it was the first time he actually ever saw moving fish. Although I showed him fish in aquaria before, he was too young to react to them, but this time he was amazed by the large school of fish swimming back and forth. The sticklebacks from the lake were absolutely huge, I estimate up to about 9cm, much bigger than the ones I ever saw in Cambridge and the ones in the ponds near the University here. I hope to go on a trip soon to observe the collective behaviour of the sticklebacks in lake Konstanz, the ponds, and streams in the area to set-up some exciting experiments on the population-specific differences of this amazing species.
New paper on how social conditions affect boldness repeatability
Our latest paper Recent social conditions affect boldness repeatability in individual sticklebacks, is now out online in Animal Behaviour (Open Access!). You can download the pdf here. ∞
Live with my sticklebacks on the Naked Scientists podcast
Recently I was invited to participate in the latest episode of the fantastic Naked Scientists podcasts series to highlight why sticklebacks are the most incredible animal on the planet!
Colour-switching sticklebacks, geckos with enough adhesive power to hold up a human, bats with built-in sonar and moles with amazing noses – this week we go in search of the world’s most incredible animals. Scientists passionate about their species put their cases to our panel. But which animal will be crowned king?
To make clear to the radio audience why sticklebacks, perhaps ordinary looking fish to most, are actually an amazing animal species I brought along 10 fellow stickles and made them change colour over the time of the hour long interactive show! You can listen to the full podcast here or just listen to my part here where I also discuss a range of other cool abilities of this great little fish.
The Naked Scientists show was brilliantly hosted by Ginny Smith, had some amazing other speakers including Hannah Rowland, Corina Logan, Nick Crumpton, and Jade Cawthray, and also aired on BBC Radio 5.
Three-spine stickleback close-up photo
I have been taking quite a lot of photos and videos of the sticklebacks recently for public engagement and wanted to share this large close-up photo with you. Although it is a three-spine stickleback, it actually only has two spines, a feature that is common amongst this species.
Click the image to get the full-size photo!
Last experimental work of PhD finished!
Today I finished my last experiment that will be part of my PhD! I have been locked away in the lab for a couple weeks, testing hundreds of fish on their personality and collective behaviour, but now analysis and writing can fully start. I must have tested close to a thousand fish in the two and a half year since the start of my PhD, most of which are now enjoying a happy end of their lives back in the wild. I have all the data of a number of exciting projects that will not need me to go back to the lab for at least half a year but I can actually not wait to test my next hypothesis! The three-spine stickleback is an amazing species to work with and I will definitely continue working with them after my PhD.
New paper on boldness, sociability and leadership in Animal Behaviour
Recent research of colleagues and I at the University of Cambridge has revealed that sticklebacks with bolder personalities are not only better leaders but also less sociable than more timid fish. The behaviour of these bolder fish shapes the dynamics of the group.
See a 4min video about the paper here: http://youtu.be/5TSim9TkXiw
Throughout the animal kingdom, individuals often live and move together in groups, from swarms of insects to troops of primates. Individual animals may benefit from being part of groups, which provide protection from predators and help in finding food. To ensure that individuals reap the benefits of togetherness, group members coordinate their behaviour. As a result, leaders and followers emerge.
Within groups, animals differ from each other in how they cope with their environment and often exhibit distinctive traits, such as boldness or sociability. Even three-spined sticklebacks, the ‘tiddlers’ collected from streams and ponds by generations of schoolchildren, can be described in terms of their personalities: some are bolder and take more risks, while others are more timid and spend more of their time hiding in the weeds.
Research carried out in the Zoology Department at the University of Cambridge suggests that observations of these tiny fish, and how they interact with one another, could provide important insights into the dynamics of social groups, including humans.
Jolle Jolles, lead author of the study, said: “Although we now know that the spectacular collective behaviours we find throughout the animal kingdom can often be explained by individuals following simple rules, little is known about how this may be affected by the personality types that exist within the group.

Experimental design. Fish were tested twice for one hour in the risk-taking task during two subsequent sessions. During the pairing session fish could see and interact with one another through a transparent partition.
“Our research shows that personality plays an important role in collective behaviour and that boldness and sociability may have significant, and complementary, effects on the functioning of the group.”
In the study, the researchers studied the behaviours of sticklebacks in tanks containing gravel and weed to imitate patches of a riverbed. The tanks were divided into two lanes by transparent partitions and randomly-selected pairs of fish were placed one in each lane. Separated by the see-through division, the fish were able to see and interact with one another.
The positions and movements of the individual sticklebacks were recorded using sophisticated tracking technology, enabling accurate comparisons to be made of each fish’s role in the collective movement of the pair.
“We found that individuals differed considerably and consistently in their tendency to approach their partner,” said Jolles. The study showed that more sociable individuals tended to be coordinated in their behaviour while less sociable individuals were more inclined to lead.
Dr Andrea Manica, reader at the Department of Zoology and co-author of the paper, added: “Our research revealed that the tendency of fish to approach their partner was strongly linked to their boldness: bolder fish were less sociable than their more timid group mates.”
Jolles explains that sociability may form part of a broader behavioural syndrome. “Our results suggest that bolder, less sociable individuals may often lead simply because they are less reluctant to move away from their partners, whereas shyer, more sociable, individuals become followers because they prioritise staying close to others,” he said.
“Differences in boldness and sociability may be expressions of underlying risk-prone or risk-averse behavioural types, as risk-averse individuals may be more motivated to group together and to respond to other individuals in order to avoid predation.”
The findings of this study suggest that leadership and group coordination can be strongly affected by personality differences in the group and that boldness and sociability may play important but complementary roles in collective behaviour.
Jolles added: “Now we know these personality traits affect the collective movements of pairs of fish, the next step is to understand their role in the functioning and success of larger, more dynamic groups.”
See a 4min video in which we explain our paper in more detail below:
Click here to download the paper.
Jolles JW, et al. (2015) The role of social attraction and its link with boldness in the collective movements of three-spined sticklebacks. Animal Behaviour, published online 2 Dec. Doi: 10.1016/j.anbehav.2014.11.004
Paper accepted on social attraction, boldness and collective behaviour
Leadership in fish affected by previous experiences and linked to personality
Leadership behaviour is affected by social experiences from previous partners and depends on an individual’s personality, as shown by our latest study with three-spined stickleback fish, now published in Behavioral Ecology.
From the political affairs we see on the news, to making decisions with your friends, leadership is all around us. But next to humans, leaders and followers can also be found in many group-living animals, such as fish, birds, and primates.
Social animals may receive benefits from grouping such as protection from predators and help in finding food. But to ensure individuals reap the benefits of grouping, they must time and coordinate their behaviour with the emergence of potential leaders and followers as a result.
Read further…
Public engagement: create interactive scientific plots online
I’m always looking for ways to make my science more interactive with the public. What better way then to visualise your data and to make them dynamic and playable! I recently found out about Plot.ly, a website that enables you to create very beautiful plots that are fully customisable and embeddable and allow manipulation and interaction from your website visitors.
What I particularly like is its link with ggplot2 in R. With some simple lines of code you can easily make a plot you created for your scientific publication interactive and online. As an example, I will create an online interactive version of one of the plots in my recent paper on leadership in sticklebacks:
Here is the online interactive version. Hover over the point and try to drag the plot or zoom in and out:
Timelapse video of a boldness session
Continuing on from yesterday’s post about the personality testing for boldness, today I made a time-lapse video from one of the sessions to get a quick overview of the actual running of the experiment. For most experiments I work with 40-64 fish per batch and potentially run multiple batches. Therefore, to be able to test all fish on the same day I test 8 fish simultaneously in 8 separate lanes for one hour and run 8 consecutive sessions in a row.
Read further…
Testing boldness in three-spined sticklebacks today
Throughout the animal kingdom, individuals have been found to behave consistently different from one another over time or across different contexts. This is now mostly referred to as “animal personality”. As part of my PhD I want to understand what role such personality traits play in the structuring and functioning of social groups, i.e. in collective behaviour.
Today I am running an experiment to investigate the consistency of risk-taking behaviour, also known as the boldness personality trait. I work with three-spined sticklebacks that I caught in wild streams near Cambridge. The three-spined stickleback is a wonderful little fish that is not only easy to work with and keep in the lab but a model system for collective behaviour and animal personality.
New paper on previous social experience and leadership
My latest paper is out in Behavioral Ecology: The role of previous social experience on risk-taking and leadership in three-spined sticklebacks. See publications or download pdf. ∞
Talk at ISBE conference, New York
I gave a talk at the fantastic ISBE Conference in New York this year, entitled Effects of heterogeneity on collective behaviour. My presentation focused on the role of the boldness and sociability personality traits on the collective movements, coordination, and leadership in pairs and small groups of three-spined sticklebacks. A pdf of the talk can be found here (link removed). ∞
Just another (cold, 12 hour) day in the lab

Often I wear a thick winter coat when working in my lab but today I forgot it.. Just on a day when I have to spent 12 hours in the lab..
Although most people will probably be enjoying another warm and sunny summer day (unless you live in Britain), I will be in my underground fish lab for 12 consecutive hours. It is about 11 degrees Celsius down here to keep the water housing the hundreds of sticklebacks nice and cool so they won’t get into breeding state and show the associated changes in territorial/mating behaviour. I am however feeling a bit chilly as well as I forgot my coat today.. By typing this I hope at least my hands and fingers will warm-up a bit.
Start of a new scientific youtube channel
I have recently started a youtube channel (here) to showcase my research projects and interests. As a scientist I believe it is important (and fun!) to engage with the public and make your work understandable to scientists and non-scientists alike. Not only because most science is ultimately payed by the tax payer, but also because one of the main goals of science is to learn more about our world and share this knowledge.
Next to publishing papers it is important to make these papers understandable so that this new knowledge can be appreciated and potentially be used by the general public. The aim with a new youtube channel is to show videos of different aspects of my experiments and projects but also of interesting aspects of social life of both human and non-human animals that reflect my research interests.
Today I would like to share a short video from a recent experiment that shows the successful tracking of five three-spined stickleback fish to investigate the role of animal personality on leadership and group movements.
“What’s your personality” song!
I am always looking for possibilities to combine my research interests with music, art or design. Luckily a couple months ago my two friends Jens Bouttery and Daan Milius, professional musician/composer and film makers, asked me to collaborate on a musical performance to explore the boundaries of music, science and art called “Triggers and Tresholds“.
We have had a couple very fruitful weekends in Cambridge during which we some great discussions about science and music and they filmed a couple shorts for the performance later this year. After their last visit here and seeing the sticklebacks and my research in my basement lab in Cambridge, Jens got very creative and within a day wrote a fantastic song about my research on animal personality! Listen to it below:
[soundcloud url=”https://api.soundcloud.com/tracks/144892230″ params=”auto_play=false&hide_related=true&show_comments=false&show_user=true&show_reposts=false&visual=true” width=”100%” height=”250″ iframe=”true” /]
It is great to work together with good friends and see how my research is translated in such a creative way!
Animal personality and its role in collective behaviour
Everyone knows that our personality plays a large role in daily life, from our need for adventure and our desire to hang out with friends, to our discipline in work and our compassion with others. But when we talk about personalities in animals, or non-human animals as I like to say, many may feel it is different. Although most people use personality related terms when talking about our pets, the majority of people may still believe personality is a uniquely human characteristic. The interesting thing is, personalities exist throughout the animal kingdom!
Until about ten years ago researchers talked about the behaviour of animals in general terms, ignoring the behavioural variation between individuals because it was considered ‘noise around the mean’. However, during the last ten years, more and more researches have shown that personalities exist in a wide range of species. From birds to bees, all species so far investigated show that individuals often behave very different from one another and do so consistently throughout their lives in a similar way like we do ourselves. For example, some individuals might be bolder or more aggressive while others are more sociable and tend to follow others.
Read further…
Talk at the Ecology & Behaviour Conference, Montpellier
Today I presented research I have recently conducted on sticklebacks to investigate the link between animal personality and leadership at the Ecology & Behaviour Conference in Montpellier: Leadership and collective behaviour in sticklebacks ∞
Prize for Best Poster, ASAB Conference, Sheffield
This year I presented my work on social attraction and boldness on sticklebacks at the Easter ASAB conference in Sheffield and won the prize for Best Poster (£100)!. You can see the full poster by clicking on the image. ∞
Talk at the IEC Behaviour Conference, Newcastle
I gave a talk at the international Behaviour Conference in Newcastle this year, entitled Role of previous social experience on leader and follower behaviour in sticklebacks ∞