Expeditionen in die Korallenriffökologie

Townsville, Australien, 19.7.12 – 14.8.12

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09.08. – 13.08.

Empty and cleaned tank setup at the end of our experiment

Empty and cleaned tank setup at the end of our experiment

Day 15: After 14 days of experiments we started to measure our organisms in closed incubations on the 9th of August. These measurements involved 104 incubations per day and lasted 3 days until all organisms will be measured.

During the whole course of the experiment we didn’t encounter any difficulties and due to good coordinated teamwork we managed to keep up with the daily and bi-weekly measurements as well as the work intensive regular cleaning of all tanks. We observed growth of all organisms in all our tanks and fortunately didn’t lose any organisms. During our measurements of the maximum quantum yield as well as the calcification measurements we could already see first effects of our light treatment as well as the increased organic matter availability.

Further analysis will now be performed in our home institutes. In addition we also took samples of coral and algae tissue for pigment analysis as well as the skeleton for the analysis of mineral structure.

Overall it was a successful experiment and we are looking forward to analyze our data. We are now very interested to see which impacts the treatments had on the different physiological levels of our organisms.

 

24.07. – 08.08.

Organisms in our experiment

Organisms in our experiment

Day 0: We started the experiment at the 24th of July and from now on measured the maximum quantum yield as indicator of photosynthetic efficiency on a daily basis as well as the calcification as an increase of buoyant weight every four days.

For our initial measurements we used closed incubation chambers which we specially prepared for our species and equipped with fiber optic cables to measure oxygen evolution parallel during the incubations via and multi-channel optode system. In order to control for equal light conditions in all incubations chamber we also had to set up a LED light system that allowed for the light adjustment above every single of in total 12 incubation chambers. This setup was also used for the final incubations after 14 days of experiments were we measured the same parameters as mentioned above from all individuals of our experiments.

During the course of the experiment we cleaned all aquaria on a regular basis to control for epiphytes and in addition we took multiple water samples to determine our carbonate system as well as the organic and inorganic nutrient regime our organisms were exposed to during the experiment.

 

19.7. – 23.7.

Setting up the incubation system for the initial incubations of our experiment

Setting up the incubation system for the initial incubations of our experiment

Just after attending the International Coral Reef Symposium (ICRS) and visiting the corals sea, offshore off Cairns I traveled with the Greyhound bus from Cairns straight to Townsville where I arrived on the night to the 19th of July.

Here I stayed nearly four weeks at the Australian Institute of Marine Science (AIMS) to do a joined experiment with the PhD student Nikolas Vogel. We investigate the combined effects of ocean acidification, increased organic nutrient availability and low light conditions on three model calcifying organisms from the Great Barrier Reef.
Our experiment consisted of a lab experiment where we exposed three reef organisms to different environmental conditions in separate aquaria while monitoring water parameters throughout the experiment.

Right after my arrival we started to setup the experiment, calibrated electrodes and measured the maximum quantum yield as indicator of photosynthetic efficiency of our organisms.

The organisms we used are the two calcifying green algae: Halimeda opuntia and Halimeda macroloba as well as the staghorn coral Acropora millepora. At the 23rd of July we measured the initial rates of photosynthesis, respiration, calcification and nutrient fluxes before we started the experiment.

Friedrich Meyer, WG Coral Reef Ecology

Curaçao, Niederlande, 14.8.12 – 28.8.12

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20.8.12

H. implexiformis in aquaria

H. implexiformis in aquaria

The past three days we have been busy collecting sponge specimens. The collections were conducted on the reefs just west of Carmabi at Snake Bay and Buoy 1. Some of the sponges, particularly the pink H. caerulea and orange spikey (S. ruetzleri) are very abundant and easy to find, but the blue H. implexiformis and purple C. caribensis are not so easy to spot and require a bit of underwater searching. However, after 3 days of collecting, we now have enough sponge specimens for the incubations, but first the sponges have to recover from the collection process and adjust to the conditions in the wet lab aquaria. The sponges will be acclimated for one week before the experiments can begin and during this time the health of the sponges will be closely monitored. In the meantime there is no shortage of work to be done and we will be busy setting up the lab and preparing for the incubation experiments.

 

17.8.12

S. ruetzleri

S. ruetzleri

I arrived safely in Curaçao where it is currently a balmy 32 °C and was met by Dr. Jasper de Goeij from the University of Amsterdam who I’m teaming up with in here in Curaçao. Jasper has been working in Curaçao for over 10 years studying coral cavities, and particularly cavity sponges, and their role in nutrient cycling on coral reefs. I’m here for two weeks to help Jasper during this short field expedition and learn some methods for working with sponges that I can apply to my own PhD work on sponges in the Red Sea. We will be working at Carmabi Reseach Station located at the opening of Piscadera Bay. With easy access to the house reefs and a beautiful beach to watch the sunset this is an ideal place to be working.

The morning of the first day at Carmabi was spent in the wet lab preparing 8 aquaria to house the four species of sponges that we will be collecting. Proper set up is critical as sponges require specific conditions to keep them healthy and even something like too many tiny air bubbles in the aquaria system can seriously harm the sponges. During the afternoon we conducted our first survey at Holiday Beach. Sponges are a dominant and colourful presence on the reefs here in Curaçao ranging from giant barrel sponges that can be over 100 years old to the thin encrusting sponges that we are searching for that are only a few mm thick. I was quickly introduced to the four species of sponges we will be studying: Halisarca caerulea, Haliclona implexiformis, Chondrilla caribensis, and Scopalina ruetzleri, also affectionately known as “orange spikey”. The next few days the team will be busy collecting sponge specimens that we will later use for incubations to examine glucose uptake.

Laura Rix, WG Coral Reef Ecology

Golfo Dulce, Costa Rica, 9.5.12 – 16.5.12

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15.5.12

Captain Taboga operating the boat.

Captain Taboga operating the boat.

Today our experienced skipper Taboga anchored the boat at the exact same spot as the day before, and we began lowering a range of sensors from the boat and logged a variety of parameters through the water column, including oxygen and CO2 concentrations, salinity, chlorophyll, and others. In between, our captain revealed some secrets of fishing during his sportsfishing trips with clients in Golfo Ducle, and his hand gestures imitating the use of a fishing rod
in addition to our lowering and pulling of sensor cables caught the eye of a pelican that was so far away I could not see it. But the pelican was observing us despite the distance, and misinterpreted our movements, thinking we were about to pull some big fish out of the water. So hoping he could have a share he landed next to the boat and watched…

Anchoring the boat.

Anchoring the boat.

Despite the slightly unfavorable conditions for field work we could collect important information and we can´t wait to analyse the samples and discuss the data with our colleagues in Bremen and San Jose! In fact, the expedition is only a small part of a larger project in which a variety of persons collaborate behind the scenes of this blog. First of all our Costa Rican partners in San Jose with whom it is a pleasure to collaborate, but also about a dozen colleagues in Bremen who directly helped with small or big favours.

So this blog is not only an effort to share our discoveries with the public, but also to say thanks to everyone involved! The next expedition is planned for summer, and we are convinced the Golfo Dulce will be more inclined to give up some of its secrets….

 

13.5.12

Celeste and Tim preparing sample bottles.

Celeste and Tim preparing sample bottles.

Consulting tide tables, weather reports and fishermen, we found ways to chose the time of day when the water is calmest, and avoid at least the moments when the currents were strongest and pulling millions of liters of water out of Golfo Dulce into the open Pacific. Sometimes this meant extending the work into the afternoons, when the rain started. The rain is warm and did not bother us much, but was more of a problem for all equipment that is not meant for use under water. It also calms the sea from wind chop, but the clouds resulted in dense darkness that makes distinguishing corals difficult, so we aimed for a balance between currents and light. Visibility under water was slightly better under the conditions we chose, but snorkelers and divers were still being pulled left and right by the swell. This would be rather funny if on a recreational excursion, but when filling sample bottles it is a real challenge. More than once we had to swam after lost bottles, and Captain Taboga even fished one out of the water with a handnet.

Nearby we met Costa Rican colleagues undertaking submarine dives from aboard the Undersea Hunter. They reported a strong swell even down to water-depth of 200 m. Nevertheless, all of us were able to cope with the situation and to obtain the most the relevant samples.

 

11.5.12

The point of view of the diver looking at a Gorgonian soft coral.

The point of view of the diver looking at a Gorgonian soft coral.

This expedition is a nice example of how research is a continuous learning process. During the previous trip to Costa Rica the team discovered a reef with mysterious bubbles. Quite a normal thing in your typical soda drink, but unusual in the sea. The purpose of this expedition was therefore to find out a bit more about the nature of this site and the chemistry of the mysterious gas bubbles. It is exiting to think that we try to find answers to questions that no one knows the answer yet. How did this reef grow and how do geological processes influence the health of the corals? Our couriosity drove us to come back with a small team at the beginning of the rainy season, which is not ideal for working in the field: When Celeste, our local research diver and marine biologist surfaced from the first dive, she confirmed these were unusual working conditions. We were all exhausted by the strong current and the surge that resulted from the long waves rolling in from the mighty Pacific.

Golfo Dulce is a popular vacation spot in summer, but in May the only tourists are surfers. And usually good surfing conditions (high swells) means unsuitable ones for diving or snorkeling. Despite being somewhat protected within the gulf, the water is not only moving divers and snorkelers any way it wants, but also suspends sediment in the water that reduce the visibility to 1 meter or less. Field work in the tropics is not always taking place in crystal clear water, after all we want to study the corals under the conditions they live in. We realised quickly that we would not be able to fulfill the whole survey programme we hoped for, but in the next days planned to adapt and make the best out of the situation.

Georgios Tsounis, WG Coral Reef Ecology

Santa Marta, Kolumbien, 14.11.11 – 31.1.13

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This is the first blog report from the ongoing collaboration between ZMT and the University of Giessen. Collaboration started with the inauguration of the German Academic Research Service (DAAD) Center of Excellence in Marine Sciences (CEMarin) in October 2010 in Santa Marta, Colombia. Afterwards, two PhD students (Corvin Eidens and Elisa Bayraktarov) started their projects on coral reef functioning in the Colombian Caribbean. Since September, their work is supported by Julian Rau, an ISATEC master student from University of Bremen and ZMT.

All three projects deal with the coral communities and reefs in four bays located within Tayrona National Park, Southeast of Santa Marta. Main goal is to identify the key environmental parameters that control the functioning of these highly diverse locations. One of these factors may be the seasonal upwelling that usually occurs between December and April and transports cooler water from greater depths to the surface.

Elisa is mainly studying the water chemistry (temperature, pH, inorganic and organic nutrient, chlorophyll and oxygen availability as well as turbidity), microbial processes (biological oxygen consumption of water column and sediments) and sedimentology (permeability, porosity, grain size, organic matter and carbonate content) in high spatial (8 stations) and temporal (monthly) resolution over a period of two years in total. She is also investigating coral bleaching patterns over space and time.

At the same time, Corvin is conducting supplementing studies at identical locations, thereby investigating benthic and pelagic community composition, primary production patterns, sediment-water coupling, coral-algae interactions and coral physiology.

Finally, Julian now starts to study succession and recruitment patterns on the seafloor and how this depends on the occurrence of pelagic and benthic herbivores, i.e. fishes and invertebrates that feed on algae. This will be a combination of descriptive and experimental studies.

All projects thereby are tightly interlinked, which offers the opportunity to generate comprehensive parallel datasets that enable us to understand functioning of these complex Caribbean coral reefs. weiter ›

Abrolhos Archipel, Brasilien, 12.4.12 – 16.4.12

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Countryside on the way back to Salvador do Bahia

Countryside on the way back to Salvador do Bahia

Within the scope of the international collaborative EU project SYMBIOCORE I have joined a pilot field campaign to the Abrolhos Archipelago off the coast of southern Bahia (Brazil), which represents the kick-off event of this collaborative effort in coral reef science. This particular field campaign has originally been initiated by our Brazilian (UFBA, Salvador do Bahia) and UK (UESSEX) SYMBIOCORE partners for seasonal comparative studies on scleractinian coral photophysiology with respect to turbidity levels and water depth along a gradient from near-shore to off-shore reefs. For this field trip the SYMBIOCORE partners CESAM (Portugal) and ZMT joined the team to contribute their expertise to on-going studies, establish first personal contacts, explore and document potential study sites and plan future collaborative projects in the region.

The coastal zone and shelf area of South Bahia harbours the southern-most warm-water reef ecosystems of the Atlantic Ocean. These marginal reef environments are still only poorly investigated and offer multiple approaches to study the functioning of key reef ecosystem processes (e.g. calcification, primary production, respiration) influenced by a number of environmental factors triggered by strong seasonality (stormy seasons from May-August and dry seasons from September-April).

St. Barbara island, the largest one of the Abrolhos archipelago

St. Barbara island, the largest one of the Abrolhos archipelago

Stormy seasons particularly influence turbidity and sedimentation within in-shore and near-shore reefs as well as in islands further off-shore (e.g. Parcel dos Abrolhos) by enforcing sediment resuspension. Coral reef ecosystems of southern Bahia are characterized by their distinct mushroom-like morphology (“chapeirois” = “big heads”). They represent the main research target during the present expedition. In comparison to for example Indo-Pacific reef ecosystems the number of scleractinian coral species in the Abrolhos region is very low and reaches only 17, of which the endemic Mussismilia braziliensis (massive growth form) represents the most dominant and main reef-building species. In addition, 3 species of Millepora hydrocorals occur in the region. Water current velocities are generally low to moderate (during stormy season) and seasonal water temperature in the area ranges from 24 – 28 °C. Tidal range is between 2-3 m.

16. – 17.4.12

Travel from Caravelas back to Salvador do Bahia. Visit of RECOR (UFBA) research facilities in Salvador do Bahia and concluding exchange with SYMBIOCORE project partners.

15.4.12

Recovery of multiparameter probes at St. Barbara island in the morning. Transfer to station 3 (Parcels dos Abrolhos). Investigation of the study site by video recordings, deployments of Manta multiparameter probes, surface sediment sampling, live coral samples for photophysiology and water column sampling. Observations: Moderate water current in shallow depth (ca. 20 cm s-1), higher turbidity than close to St. Barbara island (Secchi depth: 10 m). Complex coral formations, protruding massive coral heads (column-like), steep drop-off to 20 m depth. High coral cover (ca. 30-40 %). High fish abundance relative to in and near-shore reefs and groups of adult parrot fish (showing undisturbed feeding). Return to St. Barbara island for sampling of carbonate sediments close to the fringing reef (collection permit from national park authority received). Transfer back to Caravelas. Unloading of boat, sample storage and night stay at local hotel.

14.4.12

Christmas tree worm living on a Millepora hydrocoral

Christmas tree worm living on a Millepora hydrocoral

Transfer to station 2 (Pedra de Lixa, near-mid-shore, position: S 17° 41.591’ W 38° 59.555’). Investigation of the study site by video recording, deployment of Manta multiparameter probes, sediment sampling and water sampling. As in station 1, the team members from UFBA, UESSEX and CESAM sampled live coral colonies for photophysiological measurements. Observations: Very similar to station 1, low water currents (< 5 cm s-1), relatively high turbidity (Secchi depth: 7.7 m), although generally this site is known to show lower sedimentation rates than Pedre de Leste. Swarms of fish observed (adult parrot and surgeon fish). Evening transfer to off-shore islands (i.e. Parcel dos Abrolhos). Night snorkelling at St. Barbara island (Abrolhos national park) to investigate the fringing reef of the island and to deploy 2 Manta and Pendant probes overnight. Observations: Reduced turbidity (visibility: 10+ m). Relatively high coral cover (30%) and high abundance of fish (adult parrot fish and groupers). Sighting of a logger head turtle. Night stay close to the island.

13.4.12

The research vessel

The research vessel

Start of pilot cruise from Caravelas. A fully equipped catamaran with sufficient space for 7 scientists and 4 crew members has been rented from a local operator. Transfer to 1. Station (Pedra de Leste, near-shore reef, position: S 17° 46.560’ W 39° 03.050’). Investigation of the reef site by photo and video documentation, deployment of Manta multiparameter probes, while live coral samples have been collected for photophysiological measurements. In addition, water samples were taken for pigment analysis. Observations: low water current (< 5 cm s-1), high turbidity (Secchi depth: 7.5 m), Millepora hydrocorals are very abundant at reef crest with strong mucus sheet production, extensive macro-algae growth in shallow depth. Many hard corals covered with fine sediment. Very few fish were present, but if, then small groups of adult parrot fish. Overnight stay at the study site.

12.4.12

Transfer from Salvador do Bahia (North Bahia) to Caravelas (South Bahia).

 

 

 

 

 

Dr. Malik Naumann, WG Coral Reef Ecology

 

 

 

 

Was ist wichtiger in der Wissenschaft? Gute Ideen oder gutes Projektmanagement?

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Helle, kreative Köpfe, Wissenschaftler, die nur so sprühen vor Forschungsideen werden dringend benötigt, denn es sind die guten, neuen Ideen, die den wissenschaftlichen Fortschritt ausmachen.

Leider mangelt es jedoch oft, mal ganz abgesehen von Machbarkeit und Finanzierung, an der Umsetzung bzw. dem Abschluss solcher neuen Forschungsideen, und das liegt meiner Meinung nach vor allem am Management des entsprechenden Forschungsprojektes durch den Wissenschaftler selbst. weiter ›

Thesis committee oder Doktorvater exklusiv?

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Es gibt sie nun immer häufiger: sogenannte „thesis committees“, bestehend aus typischerweise 3-6 erfahrenen Wissenschaftlern, zur Betreuung eines Studenten (vor allem Doktoranden) und seiner Arbeit. weiter ›

Über den Sinn und Unsinn von Konferenzen

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Wissenschaftliche Konferenzen sind eine tolle Sache: Man stellt seine neuen Arbeiten einem (oft internationalem) Publikum vor, bekommt einen Eindruck der frischesten Forschungsideen und kann persönliche Kontakte mit Kollegen knüpfen. So oder so ähnlich wird es einem von allen Seiten vermittelt. Es entsteht der Eindruck als ob man sein Konferenzsäckchen so früh und so oft wie möglich schnüren sollte. weiter ›

Was darf der Nachwuchs im Mittelbau?

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Was erlauben unverschämte Junioren? Das hätte wohl Giovanni Trapattoni in die Fachbereichsratsrunde gefragt, wenn er als Lehrstuhlinhaber mit dem Antrag eines Nachwuchsgruppenleiters, Habilitanden oder Assistenten auf Prüfungsberechtigung behelligt worden wäre. weiter ›

Wissenschaftliches Arbeiten während einer Fußball-EM

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Als Wissenschaftler hat man es zu Zeiten eines Fußballgroßereignisses wie der Europameisterschaft besonders schwer. Es gibt eine ganze Reihe von Begleiterscheinungen, die ablenken und den wissenschaftlichen Alltag durcheinander bringen. weiter ›

Perfektionismus oder Überforderung?

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Immer öfter begegnen sie mir in der Naturwissenschaft: Menschen, die sehr viel Zeit und Mühe darauf verwenden die Relevanz von Nebenaspekten zu überprüfen, bzw. den Versuch unternehmen die Schwächen einer Methode zu identifizieren. weiter ›

Über den Autor

Die Arbeit für seine Diplomarbeit führte Christian Wild am Australian Institute for Marine Science in Townsville, Australien und am Alfred Wegener Institute für Polar- und Meeresforschung in Bremerhaven durch und erhielt seine Urkunde von der Universität Bremen in 2000. Seinen PhD in Meeresbiologie absolvierte er 2003 am Max Planck Institut für Marine Mikrobiologie in Bremen.