Food-web dynamics of mixed introduced and native fish communities in Aotearoa New Zealand lakes
We are offering a doctoral research scholarship to investigate lake food-web dynamics of mixed introduced and native fish assemblages in Aotearoa / New Zealand lakes. The PhD position is part of the ‘predicting future freshwater fish outcomes’ theme of Fish Futures, a 5-year interdisciplinary research programme aiming to provide knowledge and tools to enable thriving, resilient freshwater fish communities and socially just management. The programme is led by the Cawthron Institute, in collaboration with University of Canterbury, Te Arawa Lakes Trust, Te Rūnanga o Arowhenua, Ngāi Tahu ki Murihiku and Te Waimāori trust.
As part of understanding lake food-webs and population dynamics under a changing climate, a Fish Futures aim is to develop better quantitative understanding of interactions between native kōaro (Galaxias brevipinnis), smelt (Retropinna retropinna) and introduced salmonids. Using a nationally distributed selection of lakes, the lake food-web team is combining stable isotope diet quantification with otolith-derived growth rates to assess functional responses of the focal fish community to changes in lake condition (trophic status) and community composition. Individual fish-derived data will be used to calibrate food-web models to evaluate future scenarios under climate-induced changes to the lake thermal regimes and basal resources.
Research aim and approaches
We are seeking a PhD student to work within the lake food webs team to build on the work that is already underway. The scope of the project will be refined by the student, but should complement the diet, growth and modelling work already being undertaken, and contribute to practical solutions for managing fish populations in lakes. Areas of focus could include the roles of tributary or in-lake refugia for native fish, recruitment limitation, native fish thermal/hypoxia tolerance, competitive interactions and multi-species fishery management.
Supervisor: Angus McIntosh
Key qualifications and skills
For further details, see:
Does the project come with funding
Yes - $29,000 stipend pa
Final date for receiving applications
28 February 2023
Freshwater ecology lakes fish aquatic