Australian waters are home to 14 species of toothed whales and 9 species of baleen whales including the humpback whale.
PROJECT TITLE: Fine-scale song exchange in two neighbouring populations of humpback whales
RESEARCHERS: Michael Noad and Jennifer Allen
LOCATION: East coast of Australia and New Caledonia
Humpback whales sing one of the most complex songs in the animal kingdom. Songs consist of strings of sounds which form ‘phrases’ and these are repeated many times in a ‘theme’. Multiple ‘themes’ ultimately make up a song. Although every male in a population sings the same song (using the same sounds and themes sung in the same order), the song itself is in a constant state of evolution. Males learn the song each year from their peers through cultural transmission, a type of social learning.
As well as moving between individuals in one population (e.g. the east Australian population) the songs also move between populations. The best documented example of this is songs moving from west to east across the South Pacific, from east Australia through New Caledonia, Tonga, Samoa, the Cook Islands and French Polynesia, over periods of up to four or five years. This is possibly the most geographically expansive and rapid example of cultural transmission in the animal world.
This study focuses on songs sung in the east Australia and New Caledonia populations to see if there are any predictable or consistent patterns in the evolutionary changes that happen from year to year. Autonomous underwater acoustic recorders are in place during the whale migration season in 2014 and 2015 off the Sunshine Coast of Queensland and the southern coast of Ile Quen in New Caledonia. Archival data from both populations will also be used in conjunction with the current data to compare how songs have changed over the past decade.
By taking a close look at how the song changes, we can learn more about way in which whales within a population learn the song, the type of information that might be contained within different parts of the song, and the function of the song (which remains speculative). Humpback whale song is also an excellent example of cultural learning in a non-primate species. A better understanding of this could shed some light on the cultural learning processes of our own behaviours.
PROJECT TITLE: From conservation genetics to conservation genomics: assessing adaptive variation and population parameters of management significance in the endangered blue whale
Measuring up to 31 m the blue whale (Balaenoptera musculus) is the largest animal living on the planet and during the twentieth century whaling decreased their abundance to less than 1% of original numbers. While now protected from whaling, this endangered species is currently threatened worldwide from other anthropogenic (human-induced) impacts such as climate change, seismic surveys and ship traffic.
This project is using conservation genomics to answer pressing ecological and conservation-orientated questions. The first objective is to use adaptive genetic variation to determine the blue whales capacity to adapt to change and in turn illuminate their evolutionary potential at a subspecies, population and feeding aggregation level.
The second objective is to use neutral genetic variation to accurately determine other characteristics of blue whale populations that will inform their conservation, such as the distribution of a population. This will help us to understand what populations will be influenced by threats that occur in specific areas and to inform those monitoring blue whale abundance.
A key example where the findings will inform management at a regional level is at Ngari Capes Marine Park, which was formed by the State Government of Western Australia in 2012. This park includes an area where blue whales occur very close to the coast – sometimes less than 500 m from land. At a national level, it will inform the Conservation Management Plan for the Blue Whale. At an international level, it will inform the International Whaling Commission so they may enact appropriate management of blue whales worldwide.
Adaptive genetic variation: the components of an organism’s genome that allows the organism to survive and reproduce in its environment.
Conservation genomics: a new and cutting-edge field that uses information from thousands to tens of thousands of genetic markers in order to preserve biodiversity. The many genetic markers allows investigating adaptive, or functional, genetic variation. It also provides many times the number of neutral, or non-functional, genetic markers compared with traditional marker development approaches, thereby significantly increasing the power of analyses that require neutral markers.
Feeding aggregation: an area with a high density of animals because of plentiful food in the area.
Neutral genetic variation: the components of an organism's genome that do not contribute to its ability to survive and reproduce in its environment. Similarities and differences in these components can be used to identify and characterise individuals, relatives, populations, subspecies and species. They are the same components used in forensics and paternity analyses of humans.
Population: a group of animals of the same species that interbreed and live in a particular area.
Subspecies: a taxonomic group that is a subdivision of a species, usually in fairly permanent geographic isolation