Seaweed project within BalticSea 2020

Anyone who is interested in the Baltic Sea might have heard of Baltic Sea 2020 Foundation.
Baltic Sea 2020 is a foundation founded by Bjorn Carlson through a donation of 500 million SEK (55 million EUR). The Baltic Sea 2020 Foundation’s assets shouldfund projects that are action-oriented, innovative and helps to improve the knowledge of the Baltic Sea continuously until 2020. The BalticSea 2020 Foundation began its work in 2006 and has to date initiated more than 70 projects, of which 25 are ongoing.

One of these projects is about trying to re-establish bladderwrack inside Björnöfjärden, a bay outside Stockholm. Björnöfjärden is heavily eutrophicated and the water is quite turbid with particles that prevents the light from penetrating. It quickly becomes dark below the surface, so that only a few stands of seaweed survive here. Observant locals have informed us that there was plenty of seaweed in the Björnöfjärd in the past, however.

So, seaweed enthusiasts to the rescue!

Susanne Qvarfordt is ready to establish bladderwrack.

Susanne Qvarfordt is ready to establish bladderwrack.

Susanne Qvarfordt from the environment surveillance company Sveriges Vattenekologer has initiated a project that will examine what factors might prevent the seaweed population from re-establishing in Björnöfjärden.
In addition, she asked the BalticSeaWeed blog to help with our expertise!

So, during the first days of June, we collected fertile tips of bladderwrack. These were sexed (we cut the receptacles and see if they are male or female), so that we would get an appropriate ratio of males and females at each site.

Sexing seaweed is best done with a scalpell and a magnifying glass.

Sexing seaweed is best done with a scalpell and a magnifying glass.

The bladderwrack were made into small beautiful fertile bouquets which were then attached to a grid. These will be placed in the water, floating over a number of concrete plates, and hopefully make new small seaweed babies that can attach itself to the plates.

All is ready for a baby boom!

All is ready for a baby boom!

So, now we have placed three grids in Björnöfjärden and three in nearby Fjällsviks Bay, to see if any of the other actions carried out in Björnöfjärden will affect the seaweeds ability to reproduce.
So, keep your fingers crossed that no one gets caught with their anchor or fish tackle in our beautiful grids, and hope for calm weather at Midsummer full moon so that there will be many wee ones.

Placing a seaweed grid with buoys.

Placing a seaweed grid with buoys.

Around Gotland

Yessiree! It’s time to jump into the water again!

After a long winter with lots of ice, and a well deserved trip to warmer water, it was time for yours truly to submerge oneself into the cool waters of the Baltic Sea.

Field season 2013 opened on Wednesday 22 May at the scenic island of Gotland, jewel of the Baltic Sea.

For the faithful reader, it comes as no surprise that it was time for the inventory of summer reproducing bladderwrack around this beautiful island, as part of the investigation we made along the mainland coast and Gotland last year (see previous post on Tångbloggen 2012 – A seaweed odyssey).

Gotland is well known by many botanists for its amazing flora, and the orchids certainly fought for space with primroses and lily of the valley along the road as we drove north from Visby up towards our first stop just south of Lickershamn.

Orchis mascula- Early purple orchid

Orchis mascula- Early purple orchid

Unfortunately, I think most people fail to see how beautiful Gotland is below the surface. The clear water and the dense seaweed forests are magically beautiful and are conveniently found at knee-depth in the water. If you do not like to get wet, you can easily experience life below the surface with a pair of high rubber boots or waders and water binoculars.

Our second stop was out on the island Fårö, at Lauter huvud. At the moment it’s a rather low water level in the Baltic Sea. It is caused by the weather and is not unusual this time of year. But it gets a little tricky to swim when you are constantly running aground. It was easier to walk among the rauks and occasionally stick my head under the surface in order to verify single specimens of Fucus. Quite possibly the occasional tourist who stayed at the car park was wondering what we were doing. One is not exactly discreet in a bright red dry suit. Hope I did not destroy too many photographs by emerging between rauks like a jack-in-the-box.

Having swum a little off the cliff edge, where it goes from 0.5 meters deep to 15 meters, we went to today’s third and last site at Östergarn.

Here the waves rolled in with a quiet rhythm, and if I had not been busy counting, I would certainly have fallen asleep, it was so very peaceful. The sun had come out and warmed my back as I floated about. I saw plaice, viviparous eelpout (Zooarces viviparus), stickleback, and Lesser pipefish (Syngnathus rostellatus).

Plattfisken vilar bland tången.

The plaice is resting among the seaweed.

The night was spent at the nice hostel in Hemsedal, which had very comfortable beds.

Thursday morning began with a trip down to the southernmost tip of Gotland, the Hoburg. Here we encountered more nature lovers in the form of a flock of birdwatchers. The species often nests at the southern tips of both Oland and Gotland and is easily recognized by the telescope that is often worn over the shoulder.

I even saw Red-Backed Shrike (Lanius collurio), Northern Wheatear (Oenanthe oenanthe) and a yellow bird that I didn’t recognize.

The sea was calm and the swans that landed some distance away did not attack the red ball splashing around, muttering through a tube (snorkel). It was nice to see that htere were many small juvenile seaweed individuals there. Reproduction last year was apparently very successful. Always a good sign.

Our last stop for a dip was just south of Klintehamn. On the way there we visited the nice naturum center in Vamlingbo for a short break. With coffee in the body, we parked at what must be Gotland’s busiest road, and changed into work clothes.

“When you take off your pants, five cars and a bus will always appear” – Old jungle proverb

It was the only site with lots of bladders on the wrack! One might think that bladderwrack always have bladders, but no! If the site is exposed to strong wave action, no bladders are formed. This is to minimize wave grip, so that the wrack does not get torn off by the waves.

Blåsor på blåstången - inte en självklarhet.

Bladders on the bladderwrack – not always to be expected.

It was plenty of gammarids, prawns and isopods here, and I hope I got a picture of the Lesser Pipefish hiding amongst the seaweed. It was obvious that there is a lot of nutrients coming out into the water as runnof from land. The seaweed had much filamentous algae growing on them. Swimming across it reminded me of a shaggy rug.

After again having fulfilled the jungle proverb (Why?!?) we headed towards Visby and enrolled into the prison. If we get out tomorrow remains to be seen.

Global interest in Baltic seaweed

Since we launched Tångbloggen, our original Swedish blog about seaweed in the Baltic Sea, we have had over 4000 visitors from 33 different countries around the world.
It is wonderful that there is a global interest in the seaweeds of the Baltic Sea! In order to get a better overview of this interest, we took a picture of the total number of visitors per country today(2nd April 2013).

Dessa länder har besökt Tångbloggen fram till idag (2013-04-02)

These countries have visited Tångbloggen up until today (2nd April 2013)

To further spread the interest and knowledge of the Baltic Sea seaweeds, we are now heading for Bali to participate in the 21st International Seaweed Symposium.

We will of course blog live from the conference so that our followers can get the latest in seaweed research served piping hot, both here and on Tångbloggen (in Swedish).

Join us diving for seaweed

On Thursday, you can join us under the surface and experience what it is like to scuba dive WITHOUT GETTING WET OR COLD!

How on Earth will that be possible?

On Thursday 21st we will have a sneak start on World Water Day! Come to Aquaria and join the BalticSeaWeed blog, who will get into the water to check on a seaweed experiment. You can also help feeding the animals at Aquaria and get answers to everything you’ve always wanted to know about fish, and much, much more.

The program (in Swedish) is HERE, and the press release from Stockholm Universitety (also in Swedish) is HERE.

See you Thursday!

EllenS

Fucus evanescens

Fucus evanescens, is an introduced species to the Baltic Sea. That means that it did not enter the Baltic Sea by itself, but was brought here, possibly by humans. A piece of seaweed could easily have stuck to an anchor or similar. This is quite common nowadays, where boats unknowingly transport species in their ballast water from one place to another.

More information will follow.

Fucus serratus – Serrated wrack

Serrated wrack, Fucus serratus, is easily recognized by its serrated edges. In the Baltic Sea we can find serrated wrack along the Swedish coast up to the Gryt archipelago in Östergötland, where the salinity is approximately 7 psu. We have not found any observations of its distribution along any other Baltic countries coastlines. If you know of any such, please let us know.

Serrated wrack (Fucus serratus) on the Swedish coast

Serrated wrack (Fucus serratus) on the Swedish coast

Serrated wrack is sensitive to dehydration and is not as tolerant as i.e. bladderwrack to air exposure. Where we find baldderwrack and serrated wrack living together, the serrated wrack is often found slightly deeper thatn the bladderwrack. Outside the east coasts of Öland and Gotland, for example, there are wonderful forrests of serrated wrack at about 8 m depth.

Serrated wrack thrown ashore by waves often gets a more brown-orange colour before it dries and turns almost black.
In the winter, you can find frost covered seaweed when you walk along the shore.

Frozen Fucus serratus

Frozen Fucus serratus

More information will follow.

Fucus radicans – Narrow wrack

The scientific name of narrow wrack is Fucus radicans which means that it belongs in the Fucus family, together with bladderwrack, serrated wrack and spiral wrack (Fucus spiralis).

Narrow wrack is recently discovered, since it was long belived to be a dwarf morph of bladderwrack. It is not unusual that organisms are smaller in the low salinities of the Baltic Sea. Using genetic tools, narrow wrack was identified as a new species in 2005. Since then, researchers at Stockholm and Gothenburg University have studied the ecology, reproduction and genetics of the narrow wrack.

Narrow wrack (right) is thinner and more bushy than bladderwrack (left)

Narrow wrack (right) is thinner and more bushy than bladderwrack (left)

Narrow wrack is found along the Swedish coast from Öregrund to Umeå, from around Vaasa area down to Poori/Björneborg on the Finnish coast and around the Estonian island Ösel/Saaremaa (see map under The Baltic Sea fact). Narrow wrack has not been found outside the baltic Sea, as far as we know.

Narrow wrack is clonal, wich means that it reproduces by fragmentation, but it also has sexual reproduction. The individuals that have formed by fragmentation, where small branches from the plant falls off, drift away and then reattach to a rock or boulder, all have the same genetic variation as their “mother” plant. There is one plant in particular that have been very successful along the Swedish coast, where almost 80% of all individuals are one clone.