Assessing the effects of whaling on the genetic diversity of North Atlantic blue whales (Balaenoptera musculus)

Abstract

Industrial whaling in the early to mid 20th century severely depleted the population of blue whales in the North Atlantic. Due to this reduction in population it is likely that the current population of blue whales in the North Atlantic have low genetic diversity. Blue whales are an essential part of the oceans ecosystem and are currently considered endangered. Our research looks to assess the levels of genetic diversity amongst the contemporary North Atlantic blue whale population compared with the ancient pre-whaling population. The ancient samples were collected by archaeologists from ancient Viking sites found in Iceland. The contemporary samples were collected from various blue whale carcasses that had washed ashore across the eastern coast. The mitochondrial DNA of the samples were extracted, amplified and sequenced. The DNA of the ancient samples was already extracted and sequenced. Various measurements of genetic diversity were calculated and compared between the ancient and contemporary samples. Preliminary findings suggest a decrease in genetic diversity of contemporary blue whales compared to their pre-whaling ancestors. Thirteen haplotypes were found to be unique to the ancient samples, one haplotype was found to be unique in the contemporary samples, and three haplotypes were shared between the ancient and contemporary samples. A haplotype is the group of alleles that is inherited together from one organism to another from a single parent. This makes haplotypes a useful tool for examining evolution and genetics of a species.