Scientists in Victoria, Australia have revealed that the Murray cod, once-thought to be monogamous, could be playing the field.
Victoria’s Minister for Innovation, John Brumby, announced the discovery during the recent Agricultural Biotechnology International Conference (ABIC) in Melbourne.
He said that scientists from the Department of Primary Industries (DPI) had discovered that while Murray cod was believed to be monogamous, a study of the fish larvae genes shows some cod to be polygamous with pairings of one male and two females discovered in several captive spawnings.
“The more we know about the Murray cod, including its sex life, the better we will be able to manage the population levels as well as develop its export potential,” Brumby said.
Murray cod is a highly sought after fish for domestic and overseas markets, especially in Asia where warm water fish species, including the Murray cod, are worth $1 million a year to Victoria.
The Murray cod is listed as a vulnerable species with populations estimated to be less than 10% of pre-European settlement levels, hence this discovery has substantial implications for the ongoing management of Murray cod.
The study will help the conservation and management of the vulnerable species in the wild, and provide guidelines for genetically sound breeding and stock enhancement programmes.
The research team is now determining if genetically separate populations of cod have existed, or do exist, in Victoria by analysing recent cod samples collected from the Murray-Darling Basin, alongside fish scales collected up to 55 years ago, providing information on changes in the genetic structure of the wild population.
The study is one part of a larger project using advanced gene marker and reproduction technologies to enable development of selective breeding programmes for the production of bigger, more colourful and healthier cod for aquaculture purposes.
