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Ship´s log POSEIDON 451

On April 24, the German research vessel POSEIDON started for a practical training cruise for PhD students. They will learn the basic principles of the workflow onboard a research vessel, beginning with the selection of sampling sites, the handling of sampling gears, the preparation of sediment samples, and finally their description and documentation.

The cruise started on April 24 in Portimao and ends on May 1, in Lisbon. The working area of the expedition is situated in the Spanish part of the Gulf of Cádiz, where seabed structures build up or colonised by cold-water corals are the main study target.

Every day the students will report in this ship´s log on their work and life on board the research vessel POSEIDON.

Do you have questions to the scientists on board? Just send an e-mail to:

Class 1b visited MARUM

On May 7th, the kids from class 1b visited MARUM to get their shrunken cups and to have a look at our research centre.
Christian Seiter explains the sea floor drill rig MARUM-MeBo to the pupils.
Christian Reuter explains the diving robot MARUM-QUEST to the pupils.

Via internet always present on expedition: School class 1b

Pupils of the class 1b and Gerhard

Via this ship’s log the pupils of the class 1b of the elementary school Baumschulenweg in Bremen can follow the scientists on expedition. They stay in touch with the young researchers onboard and can ask questions. They actually contribute with an own experiment to the expedition.

The pupil´s cup experiment

Painted cups

The pupils of class 1b contributed their own experiment to the expedition: They want to know what happen to a styrofoam cup in the deep sea. Therefore they prepared the cups and painted them and Gerhard took them on board.
The cups were put in a net and the net was fixed at the cable of the tool. So the cups went down several hundreds of metres and then came back on board.

And this happened:

Gerhard with the cups before the dive ...

After their dive the cups look a little bit twisted and they are much smaller! They shrunk! But why?

... and after the dive.

Tuesday, April 30

Awoke to find we were under full steam in rough waters to Lisbon. Unfortunately a few of us felt rather unsteady after breakfast and so took it easy. The decks and laboratory where efficiently cleared and packed ready for the container that we hope will be waiting for us dockside in Lisbon. We were also entertained on several occasions during the day by a pod of dolphins which loved to ride in our bow wave, using us as a free ride north up the Portuguese coastline.

Gerhard checks the letter in the bottle ...

... before throwing it into the sea.

Having a break after cleaning up eyerything.

It’s a strange feeling to think we have only been at sea a week and we're trying not to be too sentimental. Having said that we put a letter in a bottle from the school children back in Germany and added a signed picture of us all which Gerald ceremoniously threw into the sea. I like to think one day it might wash up and make someone smile. Or better yet, form part of a sediment sequence at the bottom of the ocean for future oceanographers to drop a box core on top of. We just had our debriefing seminars from Claudia and Hiske which rounded off things nicely as well as providing us with a unique insight to the trials and tribulations of being a chief scientist on board.

I think regardless of our separate fields we will all now have an interest in this field and its future developments.

View out of the laboratory: Sometimes one can see the horizon ...

... sometimes only sky.

Of course our gratitude goes to the great crew on-board who have been so accommodating to us and we gave Claudia the well deserved “Golden Fahrtleiter Award 2013” for her achievements organising this cruise. Although exhausted, we've have had a wonderful experience which will stay with us for along time.

Thank you dear reader for following this blog of events.

Kindest regards
Will Brocas

Monday, April 29

Today is Monday, and at the same time the last chance for us to get samples. This evening, we will set sail to Lisbon, tomorrow, we will have to pack our equipment and to clean the labs, and on Wednesday, we will be on our way back to Bremen. During the past night, we had a thunder storm and the wind sped up. Fortunately, this morning the sea was calm enough to directly start the deployment of our sampling gears.

Everybody is happy about the successfully collected sediment core.

Marlene cuts the sediment core into 1-m long sections.

Today, we deployed the gravity corer, which is designed of a weight of 1 ton connected to a 6-m-long steel pipe. The gravity corer is lowered by the winch to the sea floor, where the corer pushes itself into the sediment due to its own weight. We were happy to see that the coring attempt was successful. Everybody was a bit afraid of to get a so-called "banana". This means the steel tube bends because it hits a rock. We also found some cold-water corals today, although not as much as expected.

A bucket full of cold-water corals, collected with grab sampler from a water depth of 480m.

Our boatswain Frank takes care of ...

... a save recovery of the gravity corer.

Simon cleans the steel tube.

We had some companions today: dolphins (or whales?).

However, all the samples we collected during the cruise would never have been succeeded without the outstanding support of the entire crew of RV POSEIDON. We therefore like to thank all of them for their friendly and professional cooperation and efficient technical assistance. Special thanks goes to Master Matthias Günther, boatswain Frank Schrage, and chief engineer Kurre Klaas Kröger.

By the way, we also saw dolphins today!! Or small whales? We are not sure about that, have look!

Please find the pupil´s questions and answers from Gerhard in the German version

Sunday, April 28

Just as we were heading to bed last night we felt the waves pick up. Unfortunately, this lead to a rough night for most, such is life at sea. Wind and waves being too strong this morning for the box and gravity corers we set about improving our luck with the Van Veen grab sampler. We were however cheerfully greeted by a homing dove that was crossing the sea and sought shelter from the wind in our rigging. A good omen? It's not Noah's ark, but we'll take it.

It appears that the sea had other ideas and so we got very wet and cold during the grab sampling. Good job no-one here had any illusions this would be a pleasure cruise. Still spirits are high and our interest in the research resulting from these efforts is ever growing. Looking forward to Claudia's debriefing at the end of the cruise and finding out more.

The wet lab on Poseidon, our main work place beside the deck (left to right: Marlene, Hiske, Sanja).

Sleep deprivation lead to the key discovery of the day. Which was that by substituting in the words “sieve” and “corals” to popular songs and singing to the mud is great way to speed up an otherwise monotonous task. Also this provides a great test of the sanity of ones fellow crew mates.

Oh . . . and then there was cake!

Tired student taking a nap in the lab.

So for tomorrow we have two plans, dependant on the sea state - fingers crossed for plan A: no grab samples anymore. We must also add “wave dodging” to the list if on deck duties, nice to be kept on our toes :)

Here’s to persistence, as personified by the homing dove, wonder what happened to him.

Best regards,

SM deckhand Benjamin and MARUM-technician Simon are on duty for the deployment of the grab sampler.

Describing and sieving, whole day long...

Saturday, April 27

First of all, we have to tell something about yesterday. We found an unidentified worm-like organism with a trunk and a transparent saccate body filled with greyish grains. We don’t know yet to which species this "worm" belongs, but Claudia contacted a colleague and now everyone is very excited to get the news, whether it’s a new species.

From left to right: Cinja, Sanja and Will having fun during the sieving.

At the end of the day, we saw another interesting species: A Portuguese Man-O-War (a kind of jellyfish, Physalia physalis), sailing by our ship. After the long working day yesterday, we woke up really tired this morning. It may also have had to do with the clouds that covered the sky and the drizzling rain during the morning. A new experience for us at sea - until now we have been very lucky with sunshine and warm temperatures. Nevertheless, for some of us it was a good chance to recover from the sunburns on the arms, necks and heads. Apart from that we had a very productive day describing and sieving twice the number of samples than the days before. Unfortunately, in one of the samples there were a lot of sponge spicules which got stuck in our hand while sieving. A very painful experience.

Have a break!

For dinner we had very tasty potato gratin – the favorite dish of Cinja :) . Now the last sample is waiting to be sieved… luckily the sun has decided to come back.

Best regards,

Who knows this worm-like organisms?

Friday, April 26

The second day of our expedition started at 8:30 with the continuation of Van Veen grab sampling. Sampling in the first station went well and we explored living and dead organisms in the grab samples such as corals, crinoids, bivalves. In the following step we proceeded by sieving samples, labeling and then preserving them. During the sampling campaign in the morning, two out of five Van Veen grab deployments failed as the grab did not release. The experience of failing taught us that working in the sea is not a success all the time!

Maryam discovered a crinoid on the sediment surface.

After a pleasant lunch, we deployed the box corer for the first time during this cruise. During the wonderful sunny afternoon (17 °C), we practiced for the first time all steps for the description and sampling of a box core. For example, all organisms in the box corer were described. In addition, it was very exciting to see different layers in the sediment sample that was taken by the box corer. We differentiated the sediment layer by color gradient and grain size. Furthermore, we fractionated the samples of the box corer by sieving, which took us the whole afternoon for only one box core sample.

Claudia shows the students how to describe and sample a box core.

All in all we had a tough day of sampling. Although, it was a great opportunity to get familiar with different methods of sediment sampling. We now successfully finished our working day and are looking forward to the new challenges of tomorrow.

Best regards,

The first box core is successfully recovered.

Our first box core: two different layers are clearly visible.

Marlene and Sanja open the front of the box core.

Thursday, April 25

Today we awoke early, think we'd better get used to it. Breakfast was good, with the steward presenting us with tasty “Pfannkuchen”. We had arrived on station over night and so started by watching as the Van Veen grab went over board. It takes some time for it to reach the sea bed approximately 500 meters below and so everyone watched intently as the cable length readout increased until it matched the depth sounding. Once we had retrieved the contents of the grab we were shown by Claudia how to categorise and describe the contents. Suddenly the marine biologist within me came out to play, however wish he was better with Latin spellings.

The students jointly describing a grab sample.

Myself and Gerhard got very wet with the job of sieving the sample through various size fractionation, but it was good to get stuck in. After all, that's essentially why we got into marine science as kids, right? Today was relatively relaxed and we worked steadily through the returning grabs. After a very nice lunch (we'll need to go on a post cruise diet) we got excited over a polychaete worm that had systematically made is burrow from alternatively over lapping small bivalve shells. It looked like something out of the film “Alien”. We had one grab just containing carbonatic rocks making this site not suitable for further deployments.

Will and Gerhard are sieving a sediment sample.

Much excitement was had seeing the cups attached to the final grab return nicely squished, which should make the children (and the little kid inside us) very happy. The day ended nicely with friendly banter while washing down the decks and a nice sense of achievement. Now we will relax and enjoy the sunset. . . .

Best regards,

Cinja takes photographs from the faunal content of a grab sample.

Gerhard determines the colour of the sediment with a Munsell color chart.

Please find the pupil´s questions and answers from Gerhard in the German version

Before the expedition...

Previously MARUM scientists Prof. Katrin Huhn and Gerhard Bartzke came with fascinating stories about marine research and experiments to visit the school class. Gerhard is one of the PhD-students who are onboard RV POSEIDON.

Wednesday, April 24

On Tuesday morning we took our flight from Bremen to Portugal and arrived in Portimao in the evening. We stayed one night in a hotel, before we embarked on RV Poseidon the next morning. The whole day we were busy with the preparation of the labs, mobilisation of the gears, meeting and a safety instruction. At 18:00 we set sail to our first study area in the Gulf of Cadiz, where we will arrive the next morning. depending on the weather conditions we plan to start sampling directly after breakfast. To let you know, who we (the scientific crew of RV Poseidon cruise P451-2) are, we just like to briefly introduce ourselves:


The participants oft he RV Poseidon expedition P451-2 in the harbour of Portimao (Portugal). First row from left to right: Maryam Shahraki, Sanja Asendorf, Hiske Fink, Claudia Wienberg. Last row from elft to right: Will Brocas, Gerhard Bartzke, Simon Mill, Marlene Baumer, Cinja Rittierott (Foto C. Rittierott).

Dr. Claudia Wienberg (Chief Scientist)

My name is Claudia and I am the chief scientist (the head of the scientific work) of this expedition. Since 2000 I am working as a Marine Geologist and since then I participated in over 15 expeditions on German and European research vessels. To be a chief scientist means to have a lot of responsibility. You have to coordinate and plan the entire cruise, the deployment of the gears and the sampling. You are the contact person for all problems and questions that may arise before, during and after the cruise. You have to arrange the cruise and sampling schedule with the captain and crew members and you have to coordinate the work of the scientists and technicians.

Dr. Hiske Fink (Co-Chief Scientist)

My name is Hiske and I am co-chief scientist during this cruise. I did my PhD at MARUM in Bremen (about cold-water corals in the Mediterranean Sea), where I’m now working as postdoc. I am marine geologist and I had the chance to participate in many cruises before. However, this is my first cruise onboard RV Poseidon. I look forward to share my knowledge and experiences about the life and work onboard a research vessel with young scientists.

Simon Mill (Technician)

Hello, my name is Simon and I’m the technician of this expedition. I’m studying production engineering at the University of Bremen, after I finished my apprenticeship as a mechatronics technician. During this cruise, I am responsible for the maintenance and deployment of the gears, these are a Van Veen grab sampler, a box corer, and a gravity corer.

Cinja Rittierott (Spanish Observer)

My name is Cinja and I am the "Spanish Observer" during this cruise. I am from Germany and I study in Osnabrück. Maybe, this sounds a bit controversal but due to my practical training within a research team of the Spanish Oceanographic Institute in Málaga (IEO) I was sent to this cruise. The sampling targets in the Gulf of Cadiz belong to Spanish territorial waters, therefore alos the seabed structure in this areas such as the mud volcanoes have Spanish names. Our first target will be the "Pipoca" mud volcanoes which means Pocorn in English. It’s the second time for me being on a cruise and as I am a student like most of the other participants it will be a great chance for me to learn more about the practical part of the marine research. The main part of my work will be the documentation of the collected samples.

Marlene Baumer

My name is Marlene. I am a student at the University of Bremen and a student worker for our chief scientist Claudia Wienberg at the MARUM in Bremen. I did my Bachelor thesis in Munich, started my masters in Bergen (Norway), and now will finish my masters in Bremen. On board of the ship I’m hoping to get a brief insight into scientific work on board of a vessel, and how to retrieve, handle and work with sediment cores and samples.

William (Will) Brocas

I am a 25 year old British guy working in MARUM-Bremen. My previous training in the U.K in geological oceanography gave me an interest in palaeoclimatology which lead me to take a PhD in Germany. Along the way I picked up an interest in marine biology and found a liking for the field of palaeoclimatology, because it requires involvement of many different types of scientists. From the fossil remains of organisms I am interested in reconstructing past climatic conditions. From this I hope to better understand possible future climate scenarios in a warmer world. I have been lucky to be involved with a couple of cruises, but all of these were in the Irish sea. I also like eating different fish dishes, which if probably a result of occasional studies in marine biology. I consider myself a bit of a “jack of all trades” in marine science, drawing on many diverse experiences.

Sanja Asendorf

My name is Sanja, I am 27 years old and I am living in Bremen. I studied Marine Environmental Sciences in Oldenburg and got my master’s degree in 2011. For my master thesis I went to Antarctica for three months, where I researched on sediment cores from a small cove on an island in the Western Antarctic Peninsula. Now, I am doing my PhD at the research institute MARUM in the work group of Marine Sedimentology. During the next 3 years I will try to disentangle the anthropogenic impact and natural climate change of the past millennium within the research areas of German Bight and Bay of Plenty on the north island of New Zealand.

Gerhard Bartzke

My name is Gerhard. I am a geoscientist and during my PhD studies, I worked in the area of numerical simulation of sediment transport processes at the MARUM, University of Bremen. I recently submitted my PhD thesis entitled “Micro-Scale Sediment - Fluid Interactions”. Throughout my PhD studies, I worked in the research field of 3D high resolution numerical modeling to investigate the physical parameters controlling the initiation of motion and subsequent sediment transport processes on a grain scaled level. Additionally, I conducted flume tank experiments for the validation of the numerical model results.

Maryam Shahraki

My name is Maryam. I am Iranian and I studied Marine Ecology at the Khoramshahr University of Marine Science & Technology in Iran. In 2011 I started a PhD at the Leibniz-Zentrum für Marine Tropenökologie in Bremen. The aim of my PhD is to figure out the importance of mangroves as fish habitats in the arid environment along the Persian Gulf. Many of the presently available mangrove studies have been completed in Brazilian and Colombian mangroves which are located in tropical rainy environments. The tidal dynamics in these environments are expected to be similar in arid locations, but seasonal differences between rainy and dry seasons could significantly differ making arid mangroves a unique area for research. Therefore, for the first time, fish assemblage composition and feeding patterns in a fully arid environment will be investigated.

Please find the pupil´s questions and answers from Gerhard in the German version

Gerhard in front of the Poseidon

A crane puts all our equipment on board.

This is Gerhards sleeping berth.

Here you get food.