Fin whales are the second largest creatures on our planet, only surpassed by blue whales. They can reach a length of around 20 meters - and require up to two tons of food per day. Accordingly, they release enormous amounts of nutrients - with significant effects on the ecosystems of the oceans. However, industrial whaling has significantly reduced their numbers. It was geared towards whale oil as a raw material and was operated particularly intensively between 1880 and an international agreement in 1986. Today the number of fin whales worldwide is estimated at about 100,000 animals; The species is considered endangered according to the Red List.
In a study, scientists from the LOEWE Center for Translational Biodiversity Genomics (TBG), the Senckenberg Biodiversity and Climate Research Center (SBiK-F) and from Icelandic and Swedish research institutions showed that whaling did not affect the genetic diversity of fin whales. For the first time, they examined 51 genomes of a North Atlantic fin whale population from Icelandic waters. Using the samples from 1989, 2009 and 2018, they developed demographic models that allow conclusions to be drawn about population changes over around 800 years. The study was published in the journal "Molecular Biology and Evolution".
The team concludes that whaling had a major impact on stocks in the North Atlantic, depleting them by up to 20 percent of their previous size in about a hundred years. However, the team also showed that different populations were affected differently by whaling, as the genomes of some animals showed little or no evidence of this depletion. "Looking at the genetic diversity of a species allows conclusions to be drawn as to whether and how well this species can adapt to new environmental conditions or changes in its population, or whether it will probably become extinct," explains the first author of the study, Magnus Wolf from SBiK-F and the Institute for Ecology, Evolution and Diversity at the Goethe University in Frankfurt. "Therefore, genomic analysis can often be used to identify developments before they become apparent. In the long-term perspective, however, we could not find any significant loss of diversity in the North Atlantic fin whales.” In addition, the scientists found no signs of further genetic defects or inbreeding.
Compared to more endangered whale species such as the blue whale or the North Atlantic right whale, the current human impact seems to be the main obstacle to the recovery of fin whales. These include, among other things, increasing shipping traffic and pollution of the seas. Fin whales are classified as an endangered species on the Red List of the International Union for Conservation of Nature (IUCN). "Genomics is developing into a key technology not only for species protection, but also helps us to understand what biodiversity actually is and how we can use it," explains Prof. Dr. Axel Janke, lead scientist on the study, scientific coordinator and spokesperson for the LOEWE Center TBG and also works at the SBiK-F and the Institute for Ecology, Evolution and Diversity at the Goethe University in Frankfurt. "Whales are not only impressive animals, but despite their long lifespan of up to one hundred years and their body size, they hardly ever develop tumors and are therefore resistant to cancer. Unraveling the genomic mechanisms causing this paradox could help us address one of the most devastating diseases in human history.”