UC student explores native crayfish sustainability

27 September 2016

A UC student will discuss her research into central Canterbury's native freshwater crayfish in an upcoming free seminar.

UC student explores native crayfish sustainability

Presenting the NTRC September seminar, Master's student Channell Thoms is investigating management strategies that would ensure sustainability of freshwater resources, and describes herself as passionate about mahinga kai species.

In an upcoming free seminar, a University of Canterbury student will discuss her research into central Canterbury’s native freshwater crayfish, including investigating its distribution, trapping efficiencies and feeding preferences.

Studying at UC’s School of Biological Sciences in the College of Science, with scholarship funding and support from the UC Ngāi Tahu Research Centre (NTRC), Channell Thoms, who is a descendant of Ngāi Tahu from Ngati Kuri hapu with whakapapa to Maungamanu, has just completed her Master’s thesis on freshwater crayfish or kekewai (Paranephrops zealandicus).

Presenting the NTRC September seminar on 29 September, Channell is investigating management strategies that would ensure sustainability of freshwater resources, and describes herself as passionate about mahinga kai species.

“Freshwater crayfish are a taonga species of New Zealand waterways that are highly valued as mahinga kai by many local iwi. Crayfish can also be an important keystone species by acting as bioengineers that create habitats for other species as well as contributing to the maintenance of stream health,” Channell says.

Crayfish are also important in stream food webs, as both grazers and predators that help to shape benthic communities as well as being prey species for larger aquatic animals, she says.

“My research focused on the native South Island crayfish and involved field surveys to determine the occurrence of crayfish in Canterbury streams, testing of alternative sampling techniques and investigating feeding. Comparisons of capture techniques included active and passive methods and also examined the use of both contemporary trapping and traditional tau-kōura. 

“My research has identified that kekewai populations are currently declining and that there are biases associated with various capture methods.”

Channell hopes that results from these studies will be used to inform management and restoration projects.

Her research supervisors Professor Islay Marsden and Professor Jon Harding are also part of the Waterways Centre for Freshwater Management which helped fund her costs for the New Zealand Freshwater Sciences conference where she was awarded Best Master’s Oral Presentation. 

Ngāi Tahu Research Centre September seminar: Distribution, trapping efficiencies and feeding trials for Kekewai, the native freshwater crayfish in central Canterbury, presented by Channell Thoms on Thursday 29 September, 2.30pm – 3.30pm in Room 208, Level 2, Te Ao Marama Building, University of Canterbury.

For further information please contact:

Kirsty Ameriks, Administrator, Ngāi Tahu Research Centre, Phone: +64 3 3642987 ext. 7042 | kirsty.ameriks@canterbury.ac.nz


Margaret Agnew, Senior External Relations Advisor, University of Canterbury
Phone: +64 3 369 3631 | Mobile: +64 275 030 168 | margaret.agnew@canterbury.ac.nz
Tweet UC @UCNZ and follow UC on Facebook


Slow judgements vs correct judgements – lessons from Australia

High Court of Australia Judge, Justice Stephen Gageler, will address recent criticism of court judgment delays in Australia, at the University of ...


Government supports native planting with new tree restoration role at UC

Two native planting and restoration projects in Canterbury have received support from the One Billion Trees Fund, including a unique project led by ...