Fucus

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Vegetation is beneficial for fish recruitment

Fish in the hand of humans – a Baltic Seminar. At the Baltic seminar last week two interesting presentations were given, one about the linkage between benthic vegetation cover and fish recruitment and production and the other one the strong impact by large fishing companies.First, Johan Eklöf, Department of Ecology, Environment and Plant Sciences, Stockholm University, presented the impact of cascading effects and the close interaction between rooted aquatic plants and seaweeds and fish recruitment of for instance pike and perch in shallow Baltic Sea bays. Shown both in more and more scientific studies and experiments.

1Large fish -plant benefits

In the first figure the positive effect of large fish is shown on the filamentous algae and how rooted aquatic plants benefit the recruitment of fish .e.g perch in shallow parts of the archipelago.

2PLants juvenlie pike

Fig. 2 shows that there seems to be a threshold of 20 % cover that is optimal for recruitment.This was followed by a presentation by Henrik Österblom, from Stockholm resilience centre about the large impact of big companies managing the fish stocks, both, on a global scale and in the Baltic Sea.

3fishmarket

The seminar ended with a panel discussion addressing the question if the fish stocks are in the hand of humans and if we will be able to find ways of sustainable use of and management of fish stocks.

4panel Balticseminar

Can the knowledge of the strong link between vegetation and fish recruitment be transferred to better management of shallow bays and coastal areas? Sofia Wikström and Gustaf Almqvist at the Baltic Sea centre, Stockholm University added to the discussion about the need of further improving our understanding of these complex ecosystems for a long-term sustainable management of fish species like pike and perch.

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Fucus radicans takes to the Royal Dramatic Theatre stage

To celebrate the 70th birthday of His Majesty King Carl XVI Gustaf, a unique show “An evening about the Baltic Sea- Hopes and threats” was given in his honour at the Royal Dramatic Theatre on the 25th of April. On stage was more than 10 scientists together with leading dignitaries from several authorities and politicians who gave lively narratives of what is happening in the Baltic Sea. Everything from the slow geological changes over the years to the formation of new species all the way to the political situation today.
1Dramaten

A truly dramatic moment was when Ett mycket dramatiskt ögonblick var när professor emeritus Ragnar Elmgren from Stockholm University spoke of what species can be found in the Baltic Sea today. Suddenly, a large Ascophyllum nodosum falls down from above, landing just behind him!

Professor Elmgren cooly states that this species has not managed to migrate into the Baltic Sea due to the low salinity. The common seaweed species that most people reckognise, the bladderwrack, is an important foundation species for life in the Baltic Sea. Many species find shelter or food in the bladderwrack.
This is the moment when Fucus radicans enters the stage, from the pocket of Ragnar. Fucus radicans has formed an own species from Fucus vesiculosus in less than a couple of thousand years. It is the only known endemic species in the Baltic Sea, which means it is not found anywhere else i the world seas.

Seaweed smells of the sea and is also edible. Someone who has tried Fucus radicans canapées (se tidigare inlägg) is the Swedish king, on a visit to the Askö Laboratory.

It is relatively easy to separate Fucus radicans and Fucus vesiculosus when they grow together in sympatry. Fucus radicans appropriate common name is narrow wrack. The thallus is much narrower that that of Fucus vesiculosus and Fucus radicans lacks the bladders that have given Fucus vesiculosus its name.
4Smal o blåstång

Between the presentation on stage, we the audience were entertained with beautiful music from the orchestra and songs. Amonst them an interpretation of ”Rönnerdal han dansar över Sjösala äng” (Rönnerdal is dancing over Sjösala meadow)by Evert Taubes, where the background was a lovely seagrass meadow.

5sjögräsäng

The show ended with all participants on stage and His Majesty the King expressed his thanks for a rewarding evening, emphasizing his own keen interest in environmental questions in general and those of the Baltic Sea in particular.

6Kungen tackar

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Nordic OIKOS poster sessions

The number of posters was very large and one poster presented by a PhD student won the award as the best poster, selected by the board of Oikos during the conference. This was number 100 with the title: “Ant larvae as a secret weapon against social parasites” by Unni Pulliainen. During the poster session lots of engaged presentations occurred.

1Winning poster Ants

Winner of “Best Poster Award”

1 a Ben presents his poster

Ben presents his poster

There were also a number of marine and aquatic posters, for some the author had the possibility to pitch their poster in 3 minutes.

Tiina Salo, now being on a post-doc, showed in her poster that Lymnea stagnalis responds more strongly to a heat wave after exposure to a mixture of micropollutants. But they recovered fast after the heat wave had passed. To feed the snails she used ecological salad. In the future experiments they will be fed leaves from different aquatic plant species.

2Tiina presents her poster

Tiina (left) pitches her poster

Several posters presented different aspects on the hot topic “ top- down – bottom-up” regulation of different ecosystems and impact of cascading effects and interactions between species. One species that creates lots of emotions is the cormorant, when establishing large populations on small islands along the Baltic coast.

4 aPelagic food-web poster

Top-down fish poster

5Cormorant poster

Bottom-up cormorant poster

From the Department of Ecology, Environment and Evolution two posters were presented, one on the long-term effect of Pilayella on the settlement of Fucus vesiculosus by Susanne Qvarfordt and the other one presented results from a master project on the Swedish west coast about two closely related Littorina snail species behaviour when placing their egg sacs on different fucoid species.

6Pylaiella påverkan på etablering av blåstång

Susanne Qvarfordt show how the effects of Pylaiella can be seen for a long time in the macroalgal community

7Littorina poster

Our poster!

The last poster that I want to present was of high interest dealing with the new crab species, the mud crab, Rhithropanopeus harrisii and its impact on the local fauna. It is just a question when this crab will arrive on the Swedish coast. Keep your eye out for it.
8Mud crab introduced

The conference ended after three intense days.

9Thanks for the conference

 

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Summary of the Askö Day

If you missed the first Askö Day, where recent and future researchers as well as course organisers met and discussed on-going and future research projects in the Baltic Sea, you can read a brief summary on the Baltic Sea Center site.

The BalticSeaWeed blog was there, of course, focusing on Fucus.

Do have a look at the lovely little film “Askö in numbers” that show areal footage of the research station.

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New publication comparing Fucus radicans and Fucus vesiculosus in Swedan and Estonia

A new scientific publication has just come out in the journal Estuarine, Coastal and Shelf Science by Ellen Schagerström, Helena Forslund, Lena Kautsky, Merli Pernoja and Jonne Kotta.

The article compared the thallus complexity and quantified the abundance and biomass of epiphytic algae and invertebrate taxa of the two fucoid species Fucus radicans and Fucus vesiculosus from sympatric sites in the Bothnian Sea on the Swedish coast and around the Estonian island Saaremaa.

Fucus radicans had a more complex thallus structure than Fucus vesiculosus within the whole study range, but both species were more complex in the Bothnian Sea compared to Estonia. The complexity of host algae did not contribute to their associated flora and fauna taxon richness; instead, the size of thalli was a good proxy for associated communities.

You can read the article HERE for free until November 8th, courtsey of Elsevier Ltd.

Fucus radicans (left) is more complex or "bushy" than Fucus vesiculosus (right)

Fucus radicans (left) is more complex or “bushy” than Fucus vesiculosus (right)

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Guest blog from the 15th Scientific Conference of the Section Phycology

At the end of Feburary, our German collegue Balsam Al Janabi attended the 15th Scientific Conference of the Section Phycology, organized by the German Botanical Society. We persuaded her to tell us about it as a Guest Blogger.

The 15th Phycology seminar took place in the beautiful marine museum of Stralsund from 23rd until the 26th of february 2014. Members from the Phycology Section of the German Botanical Society and other researchers presented a huge variety of phycology research. Organized by the University of Rostock, Prof. Dr. Ulf Karsten lead us through 59 oral presentations and 2 poster sessions, so that about 100 scientists had the change to know the research of almost all phycological disciplines and to establish contacts. English presentations were held from Bachelor-, Master-, PhD-students and Professors from Austria, Ireland, Greece, Netherlands, Mongolia as well as all over Germany, especially Kiel, Rostock, Cologne and Constance.

Phycological presentations
Eleven structured sessions, brought the audience through different principle topics with special secctions of Polar and high Alpine Phycology, the Bioacid project and a presentations in memorium to Prof. Dr. Dieter Mollenhauer (who passed away May 2013) and in honor to his contributions to his activities to promote phycology in Germany.

The antarctic research session included fascinating sessions showing the kelp system in the Antarctic seaweed system with regard to global change revealing biomass and biodiversity changes up to ecotypic differentiation. Stecher, winner of the best talk award, brought the audience below the ice of the Arctic and the DNA- and RNA of sea ice algal communities. Besides future research, also insights into the past were discovered by means of Paleolimnological studies: radiocarbon-dated sediment revealed informations about diatoms, pollen and geochemical proxies up to the Neolithic period. Analysis of biodiversity was another focus of the seminar, as for instance the diversity of the rain forest in equador. Physiological aspects, as the light regulation in diatoms explained the role of aureochromes and cryptochromes by gene silencing methods. Other approaches from terrestrial habitats revealed transcriptomic analysis as in Klebsormidium crenulatum with regard to the physiological performance under desiccation stress. Investigations about microphytes were often interesting in this seminar, as during the applied phycology session, showing the usage of algae for biogas production. The variety of disciplines was also shown by a presentation about the BIOMEX project illustrating not only the laboratory analysis of space conditions for cyanobacteria, algae and even mosses, but also the planned analysis in the international space station (ISS).

Seaweed research
The Bioacid session focused on the climate change scenaria from mesocosm experiments in the Kiel Benthocosms, a near-natural scenario analyzing a seewead community as including an experiment on the interaction of environmental stress and genetic diversity of Fucus vesiculosus. Also bacterial communities of the biofilm between the present and future scenario are compared. Fucus vesiculosus was also analyzed for their seasonality of defense as a response to the seasonal variation of micro- and macrofouling pressure. Furthermore, the gen expression under herbivore grazing was demonstrated for Fucus vesiculosus. Also other physiological aspects of brown macroalgae (Phaeophyceae) showed the iodine to salinity response in Laminaria digitata and mechanisms of photoacclimation of the giant kelp Macrocystis pyrifera revealed the relation of antioxidants with the depth at which algae appear. The role of two bacteria for morphogenesis was presented for the green algae Ulva mutabilis.

Networking and Award Ceremonies
Future network was supported by talks about the GBIF database for algae and protists as well as by insights in the SAG culture collection. During the award ceremony of best poster, Algological study and E.G. Pringsheim-Prize, the winner of the ‘Hans-Adolf von Stosch Medal’ was Prof. Dr. Michael Melkonian for his great contributions in Protistology and Phycology. He shared his experiences of decades of phycological investigations as well as appreciated cooperations.
Personally I appreciate the participation of the phycology seminar, especially due to the mixture and the connection not only of disciplines, but also of specialists and opportunities as a PhD student having the chance to discuss my methods and results with during a nice coffee brake.
//Balsam Al Janabi

Have you attended any seaweed events or do you work with seaweed and would like to tell us about it?
Feel free to contact us and become a Guest Blogger at http://www.balticseaweed.com

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The Underwater Map shows the way

Finally, you can see some of the lovely underwater nature from the Baltic Sea!

As a part of the project Naturkartan,(Nature Map) a Swedish project in the East Gotha county that aims to increase access and awareness to the nature in the county, they have also posted several short films, showing nature under the surface. Have a look at The Underwater Map (Undervattenskartan)and enjoy some summer, sun and lovely waters.

It’s wonderful to take a virtual swim and enjoy the greenery at this cold and bleak time of year. We hope that more coastal counties will pick up on the trend and choose to market their blue side.

The forrest under the surface is well worth a visit

The forrest under the surface is well worth a visit

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Roskilde revisited

Well, here we go!
After leaving the experiment with fragments (see previous post) in the basement at Roskilde University over Christmas and New Year, it was finally time to go back and see if any of the small fragments of ( Fucus radicans ) has been well behaved ande done what we want them to.

There can be MANY fragments on just one ramete of Fucus radicans

There can be MANY fragments on just one ramete of Fucus radicans

A quick refresher of the experimental background and purpose:
In the ​​Bothnian Sea, the brown macroalgae Fucus radicans has been shown to be up to 80% clonal, something that is unique among seaweed belonging to the Fucus – family.
However, it is not unusual for algae to adapt with a more clonal life cycle in brackish environments (salinity between 2-15 parts per thousand) because their sexual reproduction requires the sodium ions (NaCl – sodium chloride) from salt to work (see post about this here).

When it was discovered that Fucus radicans was clonal , it could also be described as a separate species. It was previously thought that it was a dwarf morph of Fucus vesiculosus, which is the dominant macroalgae in the Baltic Sea.

In order to reproduce clonally, fragments from one individual falls off from the parent plant and then attaches to the bottom again. But under what circumstances does this happen? What are the most favourable conditions for the fragments to re-attach? Should it be on hot summer days or cold winter nights?

Once we know this, we can understand more about when Fucus radicans is most sensitive to disturbances in the form of e.g. chemical emissions, eutrophication or construction work that affects the aquatic environment. We hope that our experiment can help to provide a better basis for management decisions concerning the Baltic Sea’s unique and fragile environment.

So, how did we set up our experiment?

We collected fragments from several plants of seaweed from different sites. Since we can neither afford nor have the time to run genetic tests on them to see that they are not all the same individual, which of course can happen when working with a species that is clonal, we made sure to get both males and females. For a longer story on startup, read the post on our startup HERE.

But on this trip it was time for me and my colleague Tiina Salo to do our first reading of the experiment.

Research is largely a matter of daring to fail, over and over again. The pile of rejected hypotheses about how one thought it might be is growing rapidly. Guess if we were surprised when our experiment had not only managed to run the whole time period without the electricity shorting out completely (except for some problems in the beginning that Tiina solved). We had results!

Two amazed PhD students could not believe their eyes.

So after checking all 96 replicates with four small fragments in each jar, I took out the bag with Fucus radicans that I had taken with me from Stockholm and we began to sort 384 new fragments into the jars for another round.

Fragments, fragments, fragments...

Fragments, fragments, fragments…

In the evening, I saw fragments when I closed my eyes.

Now, the second round is getting on and there will be a trip down again for me in early February to finish it, and hopefully get the same result as in our first round. You never know when it comes to seaweed, so keep your fingers crossed.

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The wrack wall and how storms can tear seaweed from their rocks.

In the last posts, Lena has been reporting on all the interesting finds you can make on the beach after a storm. However, these haven’t been all that much about the different species of seaweed that gets washed ashore during strong winds. So, here is a small exposé of what she found after the storm Sven (Bodil in Denmark, Xaver in Germany).

In some bays on the west coast at Tjärnö, seaweed forms large beach walls whereas in other bays you will only find a few specimens of what is growing just a couple of meters off shore. Seaweed can also come entangled in ropes and lines from far away.
Image

A photo from a bay filled with seaweed forming thick carpets. Later in the year, in the summertime, they will have been decomposed and form a beach wall covered in lush green plants. Seaweed and algae make excellent compost due and was formerly gathered to fertilize the potato patches. If you find a bay full of seaweed you can collect some and put in your garden.
Image

On other shores, like in this photo, there is only some seaweed and the red alga Furcellaria lumbricalis in a band just by the water. This is the popular sandy beach at Saltö.
Higher up on the shore some distance away, i found a pile of rope and entangled algae. On closer examination, it turned out to be seaweed from quite some distance, maybe as far away as England.

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How can you tell that the seaweed is from far away and not just from next bay or further down the coast? If you look closely at the photo underneath, you’ll see some long, brown slightly knobbly bands, which are the reproductive organs (receptacles) of Himentalia elongata, which has never been found attached in Swedish waters. The nearest site is in Norway. In the pile there is also very large bladders of Ascophyllum nodosum and a form of bladderwrack (Fucus vesiculosus)with several bladders that is much more common in areas of higher salinity that at the Swedish coast.
Image
Those of you who look closely on the photograph will notice a red algae on the bottom right, like small, finely branched bushes attached to the Ascophyllum nodosum. This is one of many Polysiphonia species, and this particular species is commonly found growing on Ascophyllum nodosum and it is called Polysiphonia lanosa.
The wrack wall consists, as one might guess, mostly of wracks that have been washed ashore, both bladderwrack and serrated wrack (Fucus serratus). The smaller specimens were still attached to blue mussels (Mytilus edulis)and others had not attached hard enough to rock or boulder and had come loose.

Different sizes of wrack washed ashore, with accessories.

Different sizes of wrack washed ashore, with accessories.

Slightly larger specimens were washed ashore still attached to pebbles. A larger plant of seaweed is very firmly attached to the rock surface and you can lift the rock by holding the seaweed sometimes. It’s not until the wracks get really big that the pull of the wave manages to tear them loose from the rock or boulder to which they are attached. But, if you look closely on the bottom of the holdfast, there is a white calcareous layer. The wrack that has come loose with holdfast has once settled as a small germling on a crustose calcareous algae or a barnacle. So what has actually come loose by the wave force is not the seaweed holdfast, but the barnacle or calcareous alga that can no longer hold on to the rock surface.

sågtångsfäste

The photo shows a holdfast from a Fucus serratus with clearly visible white parts of a calcareous crustose alga.
nyårsskål för alger
And finally – a somewhat late toast for the new year and wishing you all a happy 2014 from the BalticSeaWeed blog.

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“Cinema Seaweed”

Here in Sweden, the frost is making everything sparkling white, and our noses and cheeks red. So what could make us warmer than some Cinema Seaweed? During summer and autumn, several seaweed movies have appeared on YouTube. This is a trend that we hope will last.

Here are links to nice seaweed movies that we have come across.

Nyköpings municipality, just south of Stockholm, has really got the hang of how to show itself from its best side!
Here you can see the two localities Långskär and West Kovik. The gurgling sound you hear is when the snorkel is filled with water.

From Skälderviken down south in Skåne county we can see that both bladderwrack and serrated wrack have recovered. It is also shown that 2013 was an incredibly successful year for the brown algae Dead Man’s Rope (Chorda filum) along most of the Swedish coast.
The movie is by Virtuerack. Virtue is a resource for schools, created by the Faculty of Science at Gothenburg University and The Maritime Museum & Aquarium in Gothenburg. They also have more movies where they show how cd-discs are being placed under a jetty in the sea and become habitat for several algae and animals.

Do you have any nice seaweed movies? Please let us know.