MSc/Hons research project in eDNA detection of freshwater fish
Novel methods to monitor the presence and distribution of native and pest fish species in New Zealand freshwater
New Zealand is home to 35 species of freshwater fish, 31 of which are found nowhere else. Land use conversion as well as the introduction of invasive fish such as koi carp are impacting the abundance of native fish populations as they reduce water quality while also consuming a wide range of foods including the juveniles and eggs of native fish and the insects and plant material that our native species feed on. Today, eight species of our native fish are nationally threatened and another 12 are in decline. However, monitoring their presence and abundance in the environment is challenging, particularly since many of our native species evade detection being small, cryptic and/or nocturnal.
Better methods are urgently required to monitor the presence and abundance of our freshwater fish, but also to identify novel incursions of pest fish into new sites. A relatively novel approach to assess fish stocks is by the detection of minute quantities of environmental DNA (or ‘eDNA’) that are shed from fish into the surrounding water. This revolutionary tool could overcome many the logistical constraints associated with the collection of fish population data.