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.

A huge Carp, my friend Ziga, and a large adult Pike somewhere in the green of the Seerhein

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’.

driving-the-motor-boat

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!

view-over-the-lake

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-wetsuit-on-the-boat

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.

Here I am showing my son a school of Moderlieschen

Here showing my excited son a school of Moderlieschen

Drawing sticklebacks

I have been trying to improve my drawing skills to better illustrate how my sticklebacks behave and in what way personalities matter in collective behaviour. I still have a far way to go but this is my latest quick sketch that shows four sticklebacks with different morphologies. When I get more time on my hands after I hand in I will try to get some more elaborate drawings done!

stickleback-drawing

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.

Stickleback-closeup

Click the image to get the full-size photo! 

New stickleback project finished

taggedfishTwo part II Zoology students of mine have just finished an exciting new project with the sticklebacks! I can’t say too much about it yet but the photo can give an idea ;-) In short, it involved large numbers of tagged three-spine sticklebacks.

Stickleback spine-use project

Very recently two part IB students of mine finished a nice little experiment on the spine-use of three-spine sticklebacks. We were interested to see how personality might be related to the raising of the spines of three-spine sticklebacks as it helps them in protection against predators. Watch this close-up video that I took that nicely shows one individual stickleback raising its spines and lowering them again after feeling threatened by my presence. Hopefully soon we have the manuscript out with the findings of our study!

Last experimental work of PhD finished!

stickleback-testing-JollesToday 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 video of three-spine stickleback in my lab

Today I took a new video of the stickleback in my lab to use to talk about my work and these amazing fish during public lectures and conference presentations!

What you can see really well in this short little video is the large morphological and behavioural variation of the fish. Despite being similar in age the fish are quite different in body size as well as their colouration. Also pay attention to the spines, you can see individual fish often raising their spines at the moment they feel threatened by my presence.

One of the social housing tanks I use to house some of my hundreds of little stickebacks

One of the social housing tanks I use to house some of my hundreds of little stickebacks

Bold fish are less sociable and thereby affect leadership and group coordination

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 our research here http://youtu.be/5TSim9TkXiwSee 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.

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.

stickleback-tracking-perosnality

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.

fig1

“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:

jolles-animal-behaviour-stickleback-leadershipClick 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

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.

sticklebacks

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:

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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.
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