According to the research the coastal cod became severely depleted in the fjord during the same period. It also shows that recently, kelp and sprat experienced severe setbacks in the Hardangerfjord, Southern Norway. Now a new Strategic Institute Programme has been launched by the Institute of Marine Research launches to explore the recent events observed in the ecosystems of these fjords. The new research programme is called EPIGRAPH which is aimed at improving the causal relationships and dynamics underlying the observed changes in the two fjord ecosystems.
It is said that the EPIGRAPH is an acronym for “Ecological Processes and Impacts Governing the Resilience and Alternations in the Prorsangerfjord and the Hardangerfjord”. The research found that the rich kelp beds Laminaria hyperbora in the Porsangerfjord disappeared due to overgrazing by the green sea urchin, Strongylocentrotus droebachiensis.
The research revealed that the disappearance of kelp beds and the declining of coastal cod are observed in large parts of the coast in Central and Northern Norway. It suggests that the Porsangerfjord is a suitable model area to study the ecological interactions and causal relationships. The working hypothesis of EPIGRAPH is that the ecosystem in the Porsangerfjord is governed by predation processes and is an example of a top-down regulated system.
The institute has designed five sub-projects to challenge this hypothesis and they cover transport and distribution of egg and larvae from cod and red king crab, population dynamics and food availability in fish stocks, foraging behaviour of resident populations of harbour Phoca vitulina and grey Halichoerus grypus seals, interactions between kelp, sea urchin and red king crab and finally the biodiversity and productivity of benthic communities. According to scientists these sub-projects will generate data for modeling the ecosystem using Ecopath with Ecosim.
