Day 5 EMBS – The final sprint

It’s not fun to get the presentation slot first out on the morning after the conference dinner. But Katarina from Estonia got a good attendance and gave an interesting presentation on the zebra mussel (Dreissena polymorpha) and its impact on the ecosystem of the heavily eutrophicated Pärnu Bay in southern Estonia.

Maillie Gall from Australia told A story of two sea urchins, in which she compared the population genetics of the two sea urchin species Heliocidaris erythrogramma and Heliocidaris tuberculata to see how far their larvae spreads. She has primarily examined whether the duration of the planktonic larval stage plays a role for the spreading distance. It was very nice to rest those weary eyes on some beautiful pictures of sea urchins and Australian waters.

Jennifer Loxton held one of the conference’s coolest presentations, according to me. She showed how a bryozoan (phylum Bryozoa, it’s an animal) that came into English waters recently from Japan, reproduce like crazy. With movies and beautiful microscope images, we see that most of the currently known bryozoans form one egg bump per individual, where a larva is formed which then swims away and form a new colony. The Japanese moss animal produces up to five bumps, simultaneously! Unbelievable. The animal is red in color and thrives in cold water with high salinity, so we’ll probably not see it at the Swedish coast.

Final speaker of the conference was Paul Somerfield from Plymouth Marine Laboratory, renowned marine biologist and statistician, who talked about how to use statistics and not place too much weight on that which is odd or rare if one wants to describe an overall pattern. The presentation was entitled “Putting the species back into community analysis “. Funny, easy to understand and relevant!

Day 4 EMBS Galway

Niall McDonough from European Marine Board started the day. European Marine Board is a partnership of 35 national marine / oceanographic research institutes from 20 European countries. Recently, it has also opened up for a membership of a consortium of universities. The Board is working as a platform to develop a common understanding of what is needed and what should be prioritized within marine research in Europe, and communicate this to policy makers in the EU. There are lots of interesting publications that can be download for free on their website
For those who want to learn more about the sea, they are also running a project called Ocean Literacy, wich we will look into more closely and get back to you on.

Brenda Walles from the Netherlands present us with more information about oysters, wich we like a lot, especially with garlic. She has further investigated the possibilities of using oyster beds as erosion protection (bioengineers) on exposed coasts. Today, they are used mostly as breakwaters, but they also have a greater impact on sediment bottoms around them. The most important factor for optimum protection has proven to be the length of the reef, not surprisingly, but the oysters also have more beneficial bioengineering effects that could be utilized better than we do today. And they are so very tasty…

Katrin Bohn from Southampton University has participated in a study of re-colonization of old boat docks in Liverpool that were restored in the early 1980’s. The study was begun several years ago by Professor Stephen J. Hawkins. The restoration wincluded removing large amounts of accumulated sediment in the docks and putting back the gates in order to control the water flow. The water clarity and the oxygen concentration in the dock improved significantly during the first six years, and now mussels, sponges and sea squirts have moved in.

A small seaweed excursion in Galway

On Tuesday afternoon, we decided to take a walk along the Galway coast down to a pier leading out to a small island, where the city’s garbage treatment facility is located. We had heard rumours that there would be seaweed.
We were also told to nip into the building next to the Conference, where the Galway macroalgae research group works. We were totally awestruck when we came into the entrance and saw that this is the actual physical location of AlgaeBase. After the first shock we found the elevator and went up. Three surprised researchers looked up from their lunch. “You are looking for Mike” they concluded. “Aaahh nooo …” we replied and realized that they were already about to knock on Mike Guiry’s door (big grey door). Thankfully he was not inside (what would we have said to him?) so they showed us on a map where to best access the sea shore and find algae in the area. Thank you very much, it was most helpful!
After this near-celebrity experience we plodded on down to the hotel, changed into more suitable clothes and off we went.

There is something special about the sea air. It is richer in some way. As if it is thick with salt and sea. We came down to the pier and immediately saw that there was much seaweed! And blackberries! After a small snack we climbed down on the rocks and started picking seaweed and seashells. Nowadays, the limpet Patella vulgata is classified as extinct in Sweden. It used to be transported in currents to the Swedish west coast as larva and then grow up there but it never actually propagated in Sweden. Now, the currents have changed a bit and the larvae are not replenished anymore. Those that once existed has died out, so it’s been a long time since I found some limpet shells. Here, there were several! There were also large fine yellow shell of periwinkle Littorina obtusata (or fabalis …) who also went into my pocket.

But now for the seaweed. I briskly took off my socks and shoes, rolled up my pants and waded out a few feet to pick up a stone toped with Pelvetia caniculata, which I had not seen live before. New species! We also found lots of Ascophyllum nodosum which was much bigger and broader than at home. That’s Atlantic water for you! Here, the salinity is 35 psu, on the Swedish west coast is only around 28 psu.

My first Pelvetia caniculata

My first Pelvetia caniculata

The bladderwrack was beautiful, floating in huge, blow-rich drifts. How can you choose just a few pieces, when you want to take the whole bag full? Here, the bladders are not only one pair of bladders per year , but it really does live up to its name vesiculosus with repeated bladders along the branches. Amazing!

Bladder rich bladderwrack

Bladder rich bladderwrack

But, why are my shoes almost standing in the water? I left them on the top of the …. oh oh oh tidvatnet coming in at high speed! On with the socks and shoes quickly and onto the pier again! Whew, you’re not accustomed to such fluctuations when working in the Baltic Sea. We trudged back to the hotel again to put the seaweed in the press and wash the salt from the shells before we return to the conference.

Weed trip in Galway

Weed trip in Galway

Day 2 EMBS Galway

After a very pleasant evening with barbecue, beer and talk, most of the conference participants have managed to get out of bed and into the Bailey Allen Hall at the University for the day’s first session on “Mapping habitats and determine the ecological status”. As the title indicates, most of the presentations have a more bureaucratic character.

Opening speaker is Dr. David Connor, a marine biologist with over 30 years of experience in marine monitoring and surveying (including MESH, which maps the Baltic Sea), who is now on a loan to the EU for four years to work with the EU’s Water Framework Directive (WFD).

David shows many of the maps that they are now working on in order to get an overview of Europe’s seabeds. The maps have a resolution of 250x250m per pixel. Imagine that for a terrestrial map…However, it is much more difficult, and expensive, to make detailed maps underwater.
In addition to identifying the type of bottom substrate (sediment, rock, sand) they aim to include biological factors, energy exchanges and much more. The goal is that the European seabeds will be mapped down to 5000 meters depth, with relevant factors and good resolution.

Matt Frost followed with a talk about the benthic habitats and their classification in the EU’s Water Framework Directive, and whether there is such a thing as a sustainable habitat loss and if you can measure it to calculate when it is no longer sustainable. The basis for this work is the EU’s Habitats Directive. The data he shows includes more than one hundred researchers’ work over some years, published in the chapter “Habitat thresholds” in the report State of Seas from 2010.

Matt highlights the problems with getting hold of reliable data from all countries, and the difficulties in collecting good quality data at different depths and in different environments.
He concludes by saying that more research is needed before we can set quantitative targets for habitats, that we need to work out better methods for mapping, and that it is not possible to either set or verify quantitative habitat targets at present.

Dr. Xabier Guinda presents how they have managed to implement the EU’s Water Framework Directive for intertidal and shallow areas in Spain, France and Portugal, and the methods they have used to identify them. Primarily, they have used transects, which is the same as we do in Sweden.

Artem Isachenko presents how they have been able to identify mudflats with the presence of Arctica islandica (Ocean quahog) in the White Sea (where we from the BalticSeaWeed blog are eager to go for collecting some seaweed). To find relevant bottoms with the right type of sediment, they use side-scan sonar in Rugozerskaya strait, and received some very fine maps of bottom topography.

They even managed to interpret the sonar signal to determine the density of the large, very thick shelled Ocean quahog in the sediment, where it lives burrowed. Very convenient and comfortable!

They also checked the calculated numbers by taking pictures of the mudbottoms and count the number of Ocean quahog siphons sticking out of the mud (they are easy to recognize). The study shows that Ocean quahog can live in densities up to 400 individuals per square meter!

Henna Rinne, our Finnish colleague and friend, finish off the habitat mapping theme by presenting data from FINMARINET, which she has worked on for almost ten years. The Project is part of Natura 2000, where they have worked with habitats sandbanks (1110), reefs (1170) and small islands and islets (1620). The numbers are the code of the habitat within Natura 2000.

One of the biggest problems they have encountered when trying to map the coast of Finland is to get data. It exists, but is classified. If they get hold of the data, they are not allowed to publish it. Being from Sweden, we recognize the problem and sympathize. Today when every row boat has an echo sonar and a GPS with better resolution than many charts, one might feel it is no longer necessary to protect the depth data from Charlie (which certainly may find whatever data necessary for an invasion via Google Maps).

After a cup of tea and a stretch of the old legs, it’s time for one of the conference’s two female keynote speakers (a total of 9). Professor Maria Byrne did her bachelor here in Galway, but has since moved to Australia and work with echinoderms.
The presentation is about how the echinoderms entire life cycle, from egg to larva to juvenile and adult, is affected by changes in the aquatic environment. For a species to be able to survive in a changed environment, all stages of the life cycle must be able to be completed. Echinoderms builds up their body with calcium carbonate, so the major threats are ocean acidification (see yesterday’s talk) and increased water temperature.

Two species of sea urchins has clearly been affected. A cold-water species creeps slowly down towards Antarctica and have decreased along the Australian East Coast (Great Barrier Reef), while a temperate species have increased in number and extent as the water has become warmer.

Maria and her research group has investigated whether the response to the stress of increasing temperature and acidification are different, depending on whether the species is a polar water species or from temperate waters. It seems that the polar species are most sensitive to a decrease in pH, whereas species from temperate and tropical waters seem to have a greater ability to cope with acidification. Lowered pH seems to be the most important factor for the survival and growth of sea urchin larvae.

If one then adds a temperature rise of 3 degrees Celsius to different acidification stages and try it on the tropical sea urchin Tripneustes gratilla, commonly farmed as food in Asia, one sees that there is a clear synergistic effect on the growth of the larvae, and in later stages of life also in the gonads, which is what you eat. Thus, if it just gets a bit warmer, but not much more acidic, the urchins from tropical waters thrive down in South Australia in the future. The question is how it will affect the rest of the ecosystem. Sea urchins are known to graze heavily on seaweed!

In Starfish, they have instead seen that a rise in temperature inhibit growth. It seems that the sensitivity lies in the planktonic stage, so that species that have larvae with short planktonic stage, who does not need to build skeletons before they settle on the bottom, are less affected.

It’s always great fun to listen to someone who has worked for long in one area and it is a shame that time passes so quickly.

It’s….the 48th European Marine Biology Symposium!

This year’s edition of the EMBS, the 48th, will be held in the charming city of Galway on Ireland’s west coast.
During the week, you, dear BalticSeaWeed blog reader,will be able to keep up with the events, which we do our best to serve piping hot.

The programme is full of interesting presentations and posters. New for this year is the possibility to also present posters with a video on YouTube in order to really reach out with the results. We think that’s a brilliant idea, since Poster sessions are often a bit crowded and bustling, where long explanations and discussions can be difficult.
We also note that both Finnish and Estonian colleagues will contribute with interesting seaweed-talk.

Naturally, we hope to take a stroll along the beach to collect some seaweed for the herbarium. We have already found the seaweed products in stores.

The big question is which team will take home the Yellow Submarine this year. Don’t miss out on this!

International Seaweed Symposium – Day 4

With rested brains, it is once more time to stock up on more seaweed, both mentally and physically.

All things sweet and seaweedy

All things sweet and seaweedy

After an opening plenary lecture by Iain Neish about the importance of having a vision and being stubborn if we are to succeed with aquaculture, it was time for a cup of coffee, a slice of fruit cake and the day’s first mini-symposium.

Plenary with Iain Neish

Plenary lecture with Iain Neish

Mini Symposium: Cultivation of tropical red seaweeds

The most common species of red seaweed that are farmed are Eucheuma spp., Kappaphycus spp., Porphyra spp. and Gracillaria spp.
In Chile and Peru, it is primarily Gracillaria spp. that is farmed. In Chile, they seek to develop new methods to cultivate seaweed in the lab, instead of taking material from wild populations as many do today. They have also investigated whether it is possible to grow other commercial species.

In Malaysia, the Philippines and Indonesia, most seaweed is farmed using the fixed off-bottom technique in shallow waters. The trick is to place them deep enough so that the algae are not harmed by the intense sun during low tide.

Most algae in shallow waters are farmed using the off-bottom method.

Most algae in shallow waters are farmed using the off-bottom method.

In deeper water, they use the free-swing method, where only one end is fixed at the bottom. The downside is that it takes up quite a lot of space, and then they must be set at such a distance that they do not become entangled in each other.

The free swing method, attached at only one point.

The free swing method, attached at only one point.

Other methods for deeper water is something called single longline rafts, spider web rafts or floating triangle, depending on how you have designed the ropes. But these rafts are secured at all four corners and thus are more stationary. It also means that you can place them closer together, without risking entanglement.

In deeper waters, single longline rafts are common.

In deeper waters, single longline rafts are common.

Some growers use hanging baskets that the seaweed is floating freely in, which does not seem like a good idea to me. But this is still at the development stage. They use high pressure water hoses to remove unwanted growth of other seaweed (epiphytes).

Dr. Flower Msuya from Tanzania showed a summary of how seaweed cultivation has started and continued for the East African coast, with examples from Mauritius, Madagascar, Tanzania and Zanzibar course. The main problem to cope with is that they are now beginning to get problems with various diseases. There is much further research to do and a lot of mistakes to learn from. At the same time, a mini-symposium was held in the hall next to this, with the topic being diseases and parasites on seaweed. It’s a hot topic for the seaweed industry.

Presentations: Integrated aquaculture and introductions
In Australia, much yellowtail kingfish and tuna are farmed. At present, there is no cultured seaweed in Australia, so the researchers are now trying to find species suitable for cultivation along with fish farms in order to reduce emissions (IMTA, see previous posts). The species they are looking for are those that are good at taking up nitrogen from fish farms, but there should also be a market for the seaweed.

Kathryn Wiltshire from the University of Adelaide tested several species of red and brown seaweed to see which was best at taking up nitrogen and which grew fastest, in order to select species suitable for further experiments with the conditions that give the best performance.

Tom Schils from the University of Guam (you get extra points if you know where it is without looking it up) told us that coral reefs in Micronesia and the Pacific have very distinct algal communities, which are now threatened by introducing new varieties of these species bred for cultivation. A well-known example is the red alga Acanthophra spicifera that has taken over shallow waters on coral reefs around Hawaii.

Micronesia has a Biosecurity Plan, which seeks to identify and prevent threats to the marine environment, such as how to manage ballast water which is a great disseminator of species from one place to another.

Dr. Yang from China showed how the farming of the red alga Gracillaria spp. is along China’s 18,000-kilometer coastline and how China is now working to develop the use of integrated aquaculture. Between 1967-1980, 50-60% of China’s aquaculture consisted of cultured seaweed, mainly brown alga Saccharina japonica. Since then, the proportion of farmed fish, shrimp, crabs and clams increased. It leads to increased nitrogen load, and you need to cultivate more seaweed to not have problems with eutrophication.
The production of Gracillaria spp. is rising steadily, from 0.13 hectares in 2000 to 1,067 hectares in 2007. In 2011, the total cultivation area of Gracillaria was an astonishing 1,500 hectares!

21st International Seaweed Symposium – Day 2

After a tumultuous first day, in which the brain was saturated with impressions of color, shape, flavor and facts, we now enter to the second day. Today it is presentation at the mini-symposium on my part, and in the afternoon it is the poster session for me and Lena.

Vår poster, med gummi-receptakler.

Our poster, with rubber receptacles.

During the coffee breaks one can eat anything and everything that is based on seaweed. It gets very jello… We have also tried seaweed sausages, seaweed nuggets, seaweed-sate (this was the tastiest, very nice and spicy) and seaweed pepes (wrapped in banana leaves and grilled).

Behöver vi ens kommentera?

Should we even comment on this one?

Det finns MÅNGA sätt att använda alger i matlagning.

There are MANY ways of using algae in cooking.

We aim to find as many seaweed-products as possible to take home with us.

Weedy products

An abundance of products.

But first, a summary of the mornings scientific talks.

Mini-Symposium: Human and natural impacts on seaweed beds.

Dr. Muraoka and Dr. Fujita, both from Japan, showed how the tsunami that hit the Japanese East Coast In March 2011 has affected life in the sea. This was very interesting, because the news have generally focused on what happened on land.

In areas near the epicenter, a large acreage of seagrass meadows has disappeared. The tsunami swept over the smaller peninsulas and also destroyed many sheltered bays. But now, in 2012, it has begun to recover. However, it will take a few years, but it points in the right direction.

One of the major problems for plant life in the ocean was all the particles that were flushed out in the water. This hindered light from penetrating any deeper than 4 meters.

In Onmae Bay, there was many fish- and mussel farms before the tsunami. There were problems with fouling of the kelp species Saccharina japonica on cultivation cages and mussel ropes. An estimated 90 tons (!) of kelp grew on the farms per year. This compares to one ton of kelp from the protected rocky shores near (where sea urchins grazed extensively) and 10 tons from more wave exposed places where sea urchins could not graze.

The growth of Saccharina japonica is also favored by the nutrients coming from fish- and mussel farms. From the time of reproduction in November until May they grew a full 2 meters! The kelp is favored by good water circulation, which was higher out on the farms than on the natural hard bottom.

Today, there are large amounts of garbage from every house and car that were washed out to sea by the tsunami wave. Many breakwaters and other structures that sheltered beaches also disappeared. This has benefited the recovery of the kelp, as its worst enemy, the sea urchins, cannot graze as intensively in areas with large waves.

As they are beginning to recover from the disaster, the sea urchin fishery have commenced again. This has also helped the kelp to re-establish.

As the kelp has come back again as fouling out on the new farms, it is now a different species, Petalonia fascia, which dominates. This proved to be a problem, because it is not nearly as efficient at taking up nitrate and ammonium as Saccharina japonica. It therefore has become a problem of high nitrogen levels in the cages. There is a difference between seaweed and seaweed, you see.
So, now they are working to bring back the “right” kelp, Saccharina japonica, to avoid the kind of problems that can be caused by too much nutrients in the water. The worst of these are blooms of microalgae, so-called red tides, which can also cause shell toxin blooms, where toxic algae accumulate in mussels and other filter feeders, which becomes deadly if consumed.

So, although the system was influenced very strongly by the tsunami, it’s slowly recovering.

Presentations: Cultivation techniques II

The recurring themes in most presentations are about the importance of educating local people and create awareness. Both regarding how to grow and harvest seaweed, but also to explain the benefits and importance of creating an integrated aquaculture with many different species for an ecologically sustainable use of the ocean.

This is not a problem unique to the tropical countries. Ignorance of how to create sustainable aquaculture is found in all countries. When aquaculture first came into the limelight during the 70’s, it was first seen as the solution to the problem of protein deficiency. But it was soon discovered that large monocultures fed intensively, sometimes even with large amounts of antibiotics, were not as good as first believed. They created negative effects, and the general opinion about aquaculture turned to become negative.

To only cultivate large quantities of a single species that is in the top of the food chain is not the best way to engage in aquaculture. By co-culturing, as many gardeners know the profitability of, you can both reduce the negative effects of nutrients and also gain one or more additional products that provide income. Additionally, it provides a redundancy, not to put all eggs in one basket. Too high a density of a species makes it vulnerable to diseases and parasites. By growing more sparse, but overall more, you avoid risking the harvest to a nasty little parasite or a virus and you do not need to use antibiotics to the same extent.

21st International Seaweed Symposium – Day 1

Overwhelming! That’s the word that remains after you have entered the Bali Nusa Dua Conference Center and see all exhibitors showing 101 use of seaweed.

A phletora of products involving seaweed.

A phletora of products involving seaweed.

It is quite often I get to inform people that algae is actually a common ingredient in many of the products we use daily, such as shampoo, soap and toothpaste. But there are more represented here than I thought possible! Many companies producing various substances from seaweed are represented, followed by those that further refines the extracted elements to create all manner of products. Most exciting is of course the abundance of food with algae, both in pure form, such as seaweed snacks and jelly in different shapes (and colors!) made of agar agar extracted from seaweed. And it’s a tasting of everything! This is not a conference you go away hungry from. Possibly you have set the stage for diabetes, though.

There is no end to what gastronomy can do with seaweed!

There is no end to what gastronomy can do with seaweed!

We will post pictures, both in blog posts and in the gallery, so that you who are following the blog may take part of the diversity.

The opening ceremony of the conference began with a traditional Balinese dance and the Indonesian national anthem, followed by a number of prominent dignitaries, who in five minutes per person explained that they were pleased and proud that the conference was held here in Bali and that algae are an important part of the region’s economy and important global product. At least I think that’s what was said, when many spoke in Indonesian. But the audience seemed pleased and it was much applause. In the audience were amongst others the Fisheries Ministers from Tanzania and Morocco and Bali’s trade and industry minister.

There are a total of 38 countries participating in the symposium, most from the so-called Coral Triangle (Indonesia, Sulawesi and the Philippines) but Europe is well represented. The country with the highest number of presentations is Malaysia (57), followed by Indonesia (47), with France (31: Not bad.) in third place.

The flags of all participating nations.

The flags of all participating nations.

Mini Symposium: Integrated mulit-trophic aquaculture IMTA
Aquaculture is not without problems, as most of you probably already know. One example are fish farms, which releases nitrogen and other substances in the water around it and on the bottom under the cages. To reduce the negative effects one can grow several different species together, where the waste of one becomes the other’s nutrients. Here, seaweed is a major factor.

Alejandro H. Buschmann began by summarizing the need for more research on how seaweed work in co-cultures, if they can transfer infections between each other or to animals, and that more research is needed on integrated culture of species from different trophic levels.

Helena Abreu presented the IMTA studies conducted in Europe, which is far behind Asia in this aspect, focusing on seaweed cultivation. For example, they tried to reduce the negative environmental impacts of land-based fish farms in Norway and France by growing Ulva spp (sea lettuce) as nitrogen cleaner. The important thing is to get a seaweed product that there is a market for, either as food, fertilizer or to extract different substances from.

Interest in IMTA growing in Europe, especially since there is a need for greater production of aquaculture animals, and therefore a need for more waste treatment, but also the need for a diversity of organisms to grow, in order to have safer and more sustainable systems. The interest in seaweed is huge in Europe, not only as food but also as an ingredient in skin products and for the extraction of biofuel.

With the increased need, it is important to assess that farming and harvesting are done in a sustainable way, so that one does not get a boom-and-bust problem, taking out too much and causing the system to collaps.
In addition to the biological and technological challenges, where fish farmers should learn to cultivate a new species, there are also some regulatory barriers that need to be resolved.

Today, it is mainly Norway, Portugal, France, Ireland and Denmark that grow seaweed on a large scale in Europe. They grow mainly kelp species, mostly Saccharina latissima which can be found on our Swedish west coast, too. In Denmark, there is co-farming of kelp with trout and clams or only kelp and mussels. The kelp is grown on long ropes that hang freely in the water, looking a bit like a clothesline.

In Brittany, France, oysters and algae are farmed together. Here, it is the green alga Ulva (Sea lettuce) that is growing on oyster cages. In Portugal (using the water outside Senegal) they are cultivating kelp with sole (the flat fish), something that is also tried on the Canary Islands. In Ireland, they grow the delicious brown alga Alaria esculenta together with salmon.

In order to extract as much as possible from farmed algae there is a project to create a macroalgae biorefinery. This is collaboration between several European countries, hoping to launch a thriving seaweed culture industry also in Europe, once the current financial crisis has been resolved.

Contributed papers: Cultivation techniques

Agar is extracted from the cell walls of agar producing seaweed such as Gracillaria sp. Depending on whether the seaweed are grown in large tanks on land, in larger ponds or in the ocean, there is a variation in growth rate, growth of fouling algae, susceptibility to various diseases and the chemical content of the algae.

In Malaysia, Dr Su has assessed the pros and cons associated with each method, and also tried other methods. This included the use of floating net cages, which are often used in fish farming. They also let spores settle on fixed bottom nets and ropes, which gave a greater return on the ropes over the nets. Problems connected with ropes and nets were primarily that many other species also liked to grow there (fouling).

Dr Su from Malaysia explains her findings in culture methods.

Dr Su from Malaysia explains her findings in culture methods.

To evaluate which method was the best, not only in quantity algae produced per unit of time, they also analyzed the finished agar powder to compare the quality of the product. They found that from some areas the product contained excessive levels of lead, too high to be sold as food. The water chemistry and pollution history of an area are important to take into account when determining whether to start growing seaweed for consumption.
The main problems, though, are still grazing and unwanted growth of other species (fouling).

Norwegian salmon farming is growing rapidly. Up in Trondheim, where there are plenty of salmon farms, they have grown Saccharina latissima outside the salmon pens. The seaweed are seeded on long ropes in the lab, then hung out in the water.
Saccharina latissima is seeded in August and will not grow much during the dark winter. But when the light comes back in February to March it starts growing and keep growing strongly until June, where it reaches its maximum. This is harvest time. If you leave it any longer it begins to deteriorate and get more fouled by animals and other algae. Also, the highest concentrations of carbohydrates (alginate, laminated aria and mannitol) are in June.

Saccharina latissima grows best at 5 meters depth, where there is just the right amount of light, neither too much nor too little. Saccharina latissima grown in a salmon farm grew a full 50% more! Norway is ideally situated in order to develop a profitable seaweed faming industry and develop a more integrated aquaculture.

A study from the UK compared various plastic materials in order to find out what kind of surface and chemical composition that is best for seeding and growth of two different species of kelp (Laminaria digitata and Saccharina latissima).

They tried 12 (!) different plastics with different chemical properties, including a plastic consisting of phenol-formaldehyde resin (super toxic!) to see how sensitive the small spores are (kelp, unlike bladderwrack, has spores).

The competition between the two kelp species were checked after seeding, after 5 weeks, after being moved outdoors and after 3 months. Saccharina latissima is more tolerant to the chemical than Laminaria digitata and grew better on most plastics (few to none survived on the super toxic). It seems that plastic is not the best substrate to cultivate Laminaria digitata, but most plastics work well for growing Saccharina latissima. If you want to grow both species, the best plastics are PE, PP and PVC, apparently.

It’s Seaweed Time!

After a long and cold winter in Sweden, it is finally time for the 21st Intenational Seaweed Symposium to kick off in Bali.

There are more than 500 participants and the program is full of interesting talks, mini-symposia and posters. For full details, download the programs on the symposium website.

We will endeavour to summarize the different topics presented during the symposia, so that our followers have plenty to discuss over coffee or tea.

While we are waiting for the registration to open, here are som pictures of seaweed that we have already found, while acklimatizing to the climate and timezone (read: been on a holiday here). Enjoy!

A green entanglemetn of Chaetomorpha

A green entanglemetn of Chaetomorpha

A beautiful red algae.

A beautiful red algae.

This one reminds me of Furcellaria lumbricalis.

This one reminds me of Furcellaria lumbricalis.