From my study on Tjärnö I can see Kosterfjorden, where Sweden's first "marine" national park, Kosterhavet, will be inaugurated in September, exactly one hundred years after the establishment of the first national parks in Sweden. Perhaps it is not so surprising that the marine aspects are also behind the times in this respect – our knowledge of marine organisms and environments is, with some exceptions, decades behind the knowledge of most terrestrial ecosystems. But investments in marine research are very extensive just now, and new technologies for research into both large and small make for rapid progress. Using remote controlled submarines, bottom regions that were completely unknown to us before, even near our coasts, are being charted, and interesting discoveries of new environments alternate with frightening insights into our mismanagement of the marine resources.
On the small scale, we have developed tools for the analysis of life's smallest constituents, the genes, and with the help of genetic markers we are beginning to understand how marine organisms are related to one another, how they have moved between different sea regions and, finally, how human impact is changing their hereditary properties. My own research is precisely in this sphere, and I cannot help wondering how probable it would have been for a new plant species, as large as a dandelion and just as common, with a distribution along 500 km of our coast, and also of common occurrence in our neighbouring countries, to have been found during the last century on dry land. Not very probable that such a species would have remained undetected. But this is exactly what happened in the sea.
Narrow wrack and bladder wrack. Narrow wrack has been formed from bladder wrack in the Baltic Sea, probably less than a few thousand years ago. Such rapid speciation has seldom been documented before. Narrow wrack is the smaller one. Photographer: Lena Kautsky
Together with the research team of Lena Kautsky at Stockholm University, we have quite recently identified the new species narrow wrack, a brown alga similar to, and closely related to, bladder wrack. Narrow wrack is the dominant species around the whole Bay of Bothnia, and it is also found along the Estonian coast and in the Gulf of Finland. Narrow wrack is exciting in may ways, not only because it had managed to remain undetected despite being so common, but mainly because we know that it had been formed from bladder wrack in the Baltic Sea, probably less than a few thousands of years ago and definitely after the Baltic had come into being (8000 years ago). Such rapid speciation has very seldom been documented before. The course of events is very different from the accepted belief that the development of a new species requires hundreds of thousands of years or even longer.
From my study on Tjärnö I can see Kosterfjorden: Sweden's first "marine" national park will be inaugurated here in September, exactly one hundred years after the establishment of the first national parks in Sweden. It is perhaps not so surprising that marine affairs are lagging behind in this respect also. Photographer: Bo Johannesson
A close-up of marine snails. Photographer: Bo Johannesson
Our Galapagos
The Baltic Sea is a highly species-poor marine environment, but in spite of this it is a very exciting ecosystem. In our new Linnaeus project, we start from the premise that the Baltic Sea is both very young and also very different from the marine environments from which the species which populate the Baltic have immigrated. Since we are particularly interested in trying to understand rapid evolutionary processes, the Baltic Sea is almost a Galapagos for us. Species of Atlantic origin (and also freshwater species) have after all immigrated here over the past few thousand years. The species which have survived in the Baltic have thus very rapidly managed to adapt to an environment that is unique in the world. It is very important to try to understand how this has happened, since we need this knowledge so that we may understand whether, and under what conditions, species can adapt to rapid changes in their environment.
Genetic changes
The genetic studies of the present populations of the Baltic Sea which have been made show that several of the Baltic species are genetically different from the populations from which they originate. In many cases we know that these changed properties have made them better equipped for a life in the Baltic Sea. For example, bladder wrack has begun to reproduce vegetatively. This is a property it does not have anywhere else in the world but which makes it easier to form new plants in the low salinity of the Baltic where the eggs and sperms of bladder wrack have great difficulty in surviving. Bladder wrack normally has male and female plants which, under the influence of the full moon, release eggs and sperms into the water. It is common for marine species with external fertilisation to have some triggering factor which initiates spawning by all to increase the chance of fertilisation. The bladder wrack in the Baltic Sea, however, alternates sexual reproduction with asexual reproduction through small buds which fall to the bottom and develop into new individuals. The closely related narrow wrack uses asexual reproduction to an even greater degree and employs the same technique. We interpret this to mean that this property developed in the bladder wrack in the Baltic Sea before the narrow wrack was formed from the bladder wrack.
Researchers at work. In both summer and winter, the author collects the marine snails she is working on in order to understand speciation. Photographer: Bo Johannesson
Adaptation to low salinity
Cod in the Baltic Sea have eggs with greater than normal buoyancy to prevent the egg falling right down to the bottom in the low salinity. We suspect that there are many other adaptations which have developed during the life span, short in evolutionary terms, of the Baltic Sea. One focus in our research is to understand how adaptation to the extremely low salinity of the Baltic has occurred. In this respect we make use of knowledge from research into yeast. The research team of Anders Blomberg has identified several hundred salt genes in yeast. These genes govern the life of yeast cells in different salinities.
In the Linnaeus project, we will with the help of the salt genes of yeast to try and find the salt genes in Baltic Sea species. If we can identify these, we can, using advanced DNA analyses, find what development these genes have undergone in time in the Baltic, and also how the functions of these genes are regulated. Even though the gene as such has not changed, its expression is regulated by complex regulatory mechanisms in the cells. We can investigate these regulatory mechanisms by exposing individuals to different salinities and directly reading which genes are "on" and "off".
Tracking marine acidification
From analyses and genetic changes and gene expression, we can begin to understand how marine species have managed to conquer the Baltic Sea. With such knowledge, we can begin to have an insight into how the changes which follow in the wake of climate change may impact on marine organisms. One very definitive threat is the ongoing acidification of seas. The pH of seas has already become lower. Only a few decades ago this was considered impossible since the seas also have a high buffering capacity. Acidification chiefly affects calcium utilisation by the species and also many other processes. All round the world and especially in Sweden, experimental research is now in progress in order to try and rapidly collect data on how marine species are affected by the pH values which are expected to occur in 100-200 years. It is found that species react very differently, and that it is primarily the larvae that are affected. In our Linnaeus project we have a research team with Jon Havenhand and Mike Thordyke in the lead. Their studies have already shown that we can see only the tip of the iceberg.
Remote controlled submarine. Using remote controlled submarines, we can see bottom regions, even near our coasts, that were formerly entirely unknown to us. Here, interesting discoveries of new environments now alternate with frightening insights into our mismanagement of the marine resources. Photographer: Lisbeth Jonsson
Threatened by marine acidification. A cushion star, colonies of moss animals, some colonies of "dead men's fingers" and sea squirts can be seen here. Sea stars and moss animals belong to the groups that may be assumed to be sensitive to acidification since they have a lot of calcium structures in their bodies. Photographer: Tomas Lundälv
Tourism and fishing in national parks
My thoughts were interrupted by a well known noise – the low rumble of the shrimp trawler Carona with Rune Nilsen at the wheelhouse. He navigates easily into Örnebryggan to unload a trawl that needs repair. He is one of the fishermen who, fifteen years ago, angrily protested against Kosterfjorden being made into a nature reserve but who today works purposefully on the environmental adaptation of the local fishing which continues inside the national park. The attitude of fishermen to the national park has changed from being totally against to being carefully in favour. Now, several of them can instead see the value of developing environmentally correct fishing and in this way being able to compete with the quality and environment of their products. Finding the forms in which nature can be utilised with a long term view in sight and in a sustainable way for fishing, tourism, reindeer breeding and other activities is in sharp contrast to the attitude that prevailed when the first national parks were established. The aim of these was to conserve nature for research and to keep all other activity away (even cultural activities which were after all an essential condition for the cultural landscape that was to be preserved). A lot has thus happened in a hundred years. In this context, it seems that our first marine national park does not lag behind but is rather a forerunner as regards avoidance of the limbo which, in many cases, has been the result of top-down measures for nature conservancy. A locally anchored process was entirely critical for the success of this one.
Author
:
Kerstin Johannesson
is professor at the Department of Marine Ecology, Göteborg University and Tjärnö